This invention relates to benzodiazonine derivatives, and more particularly to benzodiazonine derivatives which bind to cholecystokinin and/or gastrin receptors. The invention also relates to methods for preparing such benzodiazonine derivatives.

Gastrin and the CCK's are structurally-related neuropeptides which exist in gastrointestinal tissue and in the CNS (see Mutt V.. Gastrointestinal Hormones. Glass G.B.J. , ed., Raven Press, N.Y., p. 169 and Nisson G., ibid, p. 127).

Gastrin is one of the three primary stimulants of gastric acid secretion. Several forms of gastrin are found including 34-, 17-, and 14-amino acid species with the minimum active fragment being the C-terminal tetrapeptide (TrpMetAspPhe-NH ₂ ) which is reported in the literature to have full pharmacological activity (see Tracey H.J. and Gregory R.A. , Nature (London), 1964, 2Q4, 935). Much effort has been devoted to the synthesis of analogues of this tetrapeptide (and the N-protected derivative Boc- TrpMetAspPhe-NH ₂ ) in an attempt to elucidate the relationship between structure and activity.

Natural cholecystokinin is a 33 amino acid peptide (CCK-33), the C-terminal 5 amino acids of which are identical to those of gastrin. Also found naturally is the C-terminal octapeptide (CCK-8) of CCK-33.

Members of this family of hormones are reported to be important in the regulation of appetite. They stimulate intestinal motility, gall bladder contraction, pancreatic enzyme secretion, and are known to have a trophic action on the pancreas. They also inhibit gastric emptying and have various effects in the CNS.

Compounds which bind to cholecystokinin and/or gastrin receptors are important because of their potential pharmaceutical use as antagonists of the natural peptides. A number of gastrin antagonists have been proposed for various therapeutic applications, including the prevention of gastrin-related disorders, gastrointestinal

ulcers, Zol linger- Ellison syndrome, antral G Cell hyperplasia and other conditions in which lowered gastrin activity is desirable. The hormone has also been shown to have a trophic action on cells of the gastrointestinal tract and so an antagonist may be expected to be useful in the treatment of cancers, particularly in the stomach.

Possible therapeutic uses for gastrin and cholecystokinin antagonists include the control of appetite disorders such as anorexia nervosa, and the treatment of pancreatic inflammation, biliary tract disease and various psychiatric disorders. Other possible uses are in the potentiation of opiate (e.g. morphine) analgesia, and in the treatment of cancers, especially of the pancreas. Moreover, ligands for gastrin/cholecystokinin receptors in the brain (so-called CCK _B receptors) have been claimed to possess anxiolytic activity.

According to the present invention, there are provided compounds of the formula

wherein one of U and V is -CHR ² -, and the other of U and V is selected from

-N(COR ⁴ )-, -CH(COR ⁴ )-, -N(SO ₂ R ⁴ )- and -CH(SO ₂ R ⁴ )-, in which

R ² is H, -COOR ⁵ (wherein R ⁵ is H or C, to C ₄ hydrocarbyl), -CONR ⁶ R ⁷ (wherein R ⁶ is H or methyl and R ⁷ is aryl, substituted aryl, or a group of the formula -(C, to

C ₄ )alkylene-W, in which W is amidino, hydroxy, acyloxy, sulphamoyl, hydroxysulphonyl, carboxy, esterified carboxy, amidated carboxy, tetrazolyl, hydroxamyl, R ¹⁴ -SO ₂ -NH-, R ¹⁴ - SO ₂ -NH-CO-, R ^H -SO , R ^,4 -SO-, R ^,4 -CO-, R ^, -CO-NH-, R ¹⁴ - CO-NH-SO-, R ¹⁴ -CO-NH-SO ₂ -, or R ^,5 -NH-SO ₂ - wherein R ¹⁴ is

H (except when R ¹⁴ is attached to a sulphur atom), C, to C ₆ alkyl, C, to C ₆ haloalkyl, aryl or substituted aryl, and R ¹⁵ is H,

C, to C ₆ alkyl, C, to C ₆ haloalkyl, aryl, substituted aryl, -OH or -CN; or R ⁶ and R ⁷ together form a carboxy-substituted propylene, butylene or pentylene group) or -COR ⁷ (wherein R ⁷ is as defined above); and R ⁴ is H, C] to C ₆ hydrocarbyl (in which up to three of the carbon atoms may be replaced by a nitrogen, oxygen or sulphur atom, provided that R ⁴ does not contain a -O-O- group), or a group of the formula -Q-R ¹⁶ wherein Q is a bond, -NR ¹⁷ - (in which R ¹⁷ is H or C, to C ₃ alkyl) or -O-, and R ¹⁶ is aryl, substituted aryl, arylalkyl or (substituted aryl)alkyl;

R is independently C, to C ₃ alkyl,

R ¹ is H or C, to C ₁₅ hydrocarbyl wherein one or more hydrogen atoms may be replaced by halogen atoms, and one carbon atom may be replaced by a nitrogen, oxygen or sulphur atom; R ³ is independently halo, alkyl, alkoxy, -NO ₂ , -NH ₂ or -NHCOR ⁵

(wherein R ⁵ is as defined above);

X is H and Y is H or C, to C, ₀ hydrocarbyl wherein one or more hydrogen atoms may be replaced by halogen atoms, and one carbon atom may be replaced by a nitrogen, oxygen or sulphur atom; or X and Y together are =O or =CH ₂ ;

Z is H, Cj to C _]S hydrocarbyl (in which one or more hydrogen atoms may be replaced by a halogen atom, and up to three of the carbon atoms may be replaced by a nitrogen, oxygen or sulphur atom, provided that Z does not contain a -O-O- group) or -(CHR ^I8 ) _m -R ⁸ (wherein R ¹⁸ is H or C, to C ₃ alkyl and R ⁸ is phenyl, substituted phenyl or a group of the formula -COOR ⁹ or -CONR'R ¹⁰ , in which R ⁹ and R ¹⁰ are independently H or C, to C ₆ alkyl, or R ⁹ and R ¹⁰ together form a propylene, butylene, pentylene or hexylene group); m is from 1 to 3; and n and p are independently from 0 to 3, and pharmaceutically acceptable salts thereof.

Preferably, U is -CHR ² - and V is -N(COR ⁴ )-.

The term "hydrocarbyl", as used herein, refers to monovalent groups consisting of carbon and hydrogen. Hydrocarbyl groups thus include alkyl, alkenyl, and alkynyl groups (in both straight and branched chain forms), cycloalkyl (including polycycloalkyl), cycloalkenyl, and aryl groups, and combinations of the foregoing, such as alkylaryl, alkenylaryl, alkynylaryl, cycloalkylaryl, and cycloalkenylaryl groups,

A "carbocyclic" group, as the term is used herein, comprises one or more closed chains or rings, which consist entirely of carbon atoms. Included in such groups are alicyclic groups (such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and adamantyl), groups containing both alkyl and cycloalkyl moieties (such as adamantanemethyl), and aromatic groups (such as phenyl, naphthyl, indanyl, fluorenyl, (l ,2,3,4)-tetrahydronaphthyl, indenyl and isoindenyl).

The term "aryl" is used herein to refer to aromatic carbocyclic groups, including those mentioned above.

A "heterocyclic" group comprises one or more closed chains or rings which have at least one atom other than carbon in the closed chain or ring. Examples include benzimidazolyl, thienyl, furanyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, oxazolyl, pyrrolidinyl, pyrrolinyl, imidazolidinyl, imidazolinyl, pyrazolidinyl, tetrahydrof uranyl, pyranyl, pyronyl, pyridyl, pyrazinyl, pyridazinyl, piperidyl, piperazinyl, moφholinyl, thionaphthyl, benzofuranyl, isobenzofuryl, indolyl, oxyindolyl, isoindolyl, indazolyl, indolinyl, 7-azaindolyl, isoindazolyl, benzopyranyl, coumarinyl, isocoumarinyl, quinolyl, isoquinolyl, naphthridinyl, cinnolinyl, quinazolinyl, pyridopyridyl, benzoxazinyl, quinoxadinyl, chromenyl, chromanyl, isochromanyl and carbolinyl.

The terms "halogen" and "halo" , as used herein, refer to any of fluorine, chlorine, bromine and iodine. Most usually, however, halogen substituents in the compounds

of the invention are chlorine or fluorine substituents.

When R ¹⁴ or R ¹⁵ is a substituted aryl group, the substituents are preferably from one to three (usually one) in number and are preferably selected from the groups recited above for R ³ . When R ⁷ is a substituted aryl group or R ⁸ is a substituted phenyl group, the substituents are preferably from one to three (usually one) in number and are preferably selected from the groups recited above for R ³ or carboxyl. When R ¹⁶ is a substituted aryl group, the substituents are preferably from one to three (usually one) in number and are preferably selected from the groups recited above for R ³ or W.

When R ³ is an alkyl or alkoxy group, or R ¹⁶ contains an alkylene group, such groups generally contain from 1 to 6 carbon atoms, and more usually from 1 to 3 carbon atoms.

Preferably, R ¹ is H, C, to C ₆ alkyl or cycloalkyl-(C, to C ₆ )alkyl. For example, R ¹ may be H, t-butyl methyl, cycloheptylmethyl or (l-adamantyl)methyl.

R ⁴ is preferably H, methyl, methoxy, carboxymethylene, carboxyethylene, benzyloxy or a group of the formula -NH-Ar (wherein Ar is an aromatic group such as methylphenyl, carboxyphenyl, dicarboxyphenyl, dichlorophenyl, naphthyl or indolyl).

When R ⁸ is substituted phenyl, the (or each) substituent is preferably selected from the groups recited above for R ³ and W. For example, the (or each) substituent may be selected from chloro, methoxy and amino.

R ⁸ is preferably t-butyloxycarbonyl, ethoxycarbonyl, pyrrolidinoyl, phenyl, 3- methoxyphenyl, 4-methoxyphenyl, 3-chlorophenyl, 4-chlorophenyl or 3-aminophenyl.

When X is H, Y is preferably H, -OH or -CH ₃ .

The invention also comprehends derivative compounds ("pro-drugs") which are degraded in vivo to yield the species of formula (I). Pro-drugs are usually φut not

always) of lower potency at the target receptor than the species to which they are degraded. Pro-drugs are particularly useful when the desired species has chemical or physical properties which make its administration difficult or inefficient. For example, the desired species may be only poorly soluble, it may be poorly transported across the mucosal epithelium, or it may have an undesirably short plasma half-life. Further discussion of pro-drugs may be found in Stella, V. J. et al, "Prodrugs", Drug Delivery Systems, pp. 112-176 (1985), and Drugs. 29, pp.455-473 (1985).

Pro-drug forms of the pharmacologically-active compounds of the invention will generally be compounds according to formula (I) in which free acid groups have been esterified or amidated. Included in such esterified acid groups are groups of the form -COOR ¹¹ , wherein R ¹¹ is C, to C ₅ alkyl, phenyl, substituted phenyl, benzyl, substituted benzyl, or one of the following:

Amidated acid groups include groups of the formula -CONR ¹² R ¹³ , wherein R is H, C, to C ₅ alkyl, phenyl, substituted phenyl, benzyl, or substituted benzyl, and R ¹³ is -OH or one of the groups just recited for R ¹² .

Pharmaceutically acceptable salts of the acidic compounds of the invention include salts with alkali metals and alkaline earth metals, such as sodium, potassium, calcium and magnesium, and salts with organic bases. Suitable organic bases include amines such as N-methyl-D-glucamine.

Pharmaceutically acceptable salts of the basic compounds of the invention include salts derived from organic or inorganic acids. Suitable acids include hydrochloric acid, phosphoric acid, oxalic acid, maleic acid, succinic acid and citric acid.

The compounds of the invention exist in various enantiomeric and diastereomeric forms. It will be understood that the invention comprehends the different enantiomers and diastereomers in isolation from each other, as well as mixtures of enantiomers and

SUBSTITUTE SHEET {RULE 26)

diastereomers.

Figures 1 to 12 depict reaction schemes which may be employed to prepare compounds according to the invention.

The reaction scheme illustrated in Figure 1 is suitable for preparing compounds (such as the compound of Example 1), in which Z is a group of the formula -CH ₂ COOR ⁹ . l ,2,3,4-Tetrahydro-9H-pyrido[3,4-b]indole (1) is first reacted with benzylchloroformate, or other suitable reagent, to protect the nitrogen atom of the piperidine moiety. The partially N-protected product (2) is then admixed with sodium hydride in a suitable solvent (such as DMF), and a bromoacetic acid ester is then added to form compound (3). The nitrogen atom of the piperidine moiety of compound (3) is then deprotected (e.g. by hydrogenation over palladium/charcoal), and the resulting product (4) is then reacted with an isocyanate (R ^l6 NCO). The product (5) of this reaction is dissolved in a suitable solvent (such as methanol), and ozone is bubbled through the solution to form the desired product (6).

Figure 2 illustrates a reaction scheme which is suitable for preparing compounds in which Z is benzyl or substituted benzyl. In this case, the nitrogen atom of the piperidine moiety of compound (1) is protected using a reagent such as di-t-butyl dicarbonate, and the partially N-protected product (7) is reacted with sodium hydride and benzyl bromide or a substituted benzyl bromide. The reaction product (8) is then deprotected using trifluoroacetic acid to form compound (9). This is then reacted with an isocyanate and then with ozone, in a manner analogous to that described above in connection with Figure 1.

Compounds in which Z is a pyrrolidinoylmethyl group may be prepared by the reaction scheme which is depicted in Figure 3. Compound (6), which may be prepared as shown in Figure 1 , is treated with trifluoroacetic acid to yield the carboxylic acid derivative (12). This is then reacted with pyrrolidine to form the desired compound (13).

Compounds in which X is hydrogen and Y is -OH may be obtained by the reaction which is illustrated in Figure 4. In this case, compound (11), obtained by the reaction scheme illustrated in Figure 2, is treated with sodium borohydride to produce the desired derivative (14).

Compounds according to the invention in which X and Y together form a methylene group may be obtained by the reaction scheme illustrated in Figure 5. Compound (8), obtained as an intermediate in the reaction scheme shown in Figure 2, is treated with ozone to provide the benzodiazonine (15). μ-Chloro-μ-methylene- [bis(cyclopentadienyl)titanium]dimethylaluminium is then added to a solution of the compound (15) to form compound (16). The N-protecting group is then removed using trifluoroacetic acid to form compound (17). This is then reacted with an isocyanate to produce the desired compound (18).

Compounds in which X is H and Y is -CH ₃ may be prepared by the reaction scheme illustrated in Figure 6. In this scheme, compound (16), which is formed as an intermediate in the reaction scheme illustrated in Figure 5, is reduced by hydrogenation over palladium on charcoal to form compound (19). The N-protecting group is then removed using trifluoroacetic acid, and the resulting compound (20) is then reacted with an isocyanate in a manner analogous to that shown in Figure 5.

Figure 7 illustrates a general scheme whereby compounds of the invention in which R ¹ and R ² are other than hydrogen may be prepared from various tetrahydrocarbolines and 1,2,3,4-tetrahydrocarbazoles. In Figure 7, U ¹ and V ¹ represent the groups defined above for U and V, respectively, or suitably protected derivatives thereof.

The general scheme shown in Figure 7 is exemplified in Figure 8 for the case in which U is -CH(CO ₂ H)τ and V is -N(COR ⁴ )-. The L-tryptophan ester (22) is reacted with an aldehyde to form the 1 , 2, 3,4-tetrahydro-9H-pyrido[3,4-b]indole derivative (23). This is then reacted with an acid chloride to form compound (24), and this in turn is reacted with benzyl bromide (or a substituted benzyl bromide) to form derivative (25). This is then reacted with ozone to form the benzodiazonine (26), and

the 5-carboxyl group is. then deprotected by catalytic hydrogenation to yield the desired compound (27).

Compound (27) may be used to provide further derivatives, as shown in Figure 9. For example, the 5-carboxyl group may be reacted with an amine (such as glycine benzyl ester p-toluene sulphonate) to form the amide (28). This is then subjected to catalytic hydrogenation to yield the free acid compound (29).

Compounds in which R ¹ is other than hydrogen may also be formed by means of a reaction scheme such as that illustrated in Figure 10. Tryptamine (30) is reacted with an aldehyde to foπn the substituted l,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole (31). Reaction of this compound with succinic anhydride yields the compound (32), which is then reacted with benzyl bromide (or a substituted benzyl bromide) to form compound (33). This is then reacted with ozone to form the benzodiazonine (34), which in turn is treated with hydrogen over a palladium on charcoal catalyst to yield the desired compound (35).

Compounds in which R ⁴ is a group of the formula -NH-R ¹⁶ may be obtained by means of the reaction scheme illustrated in Figure 11. In this scheme, trans-2- nitrocinnamaldehyde (36) is reduced to 2-nitrocinnamyl alcohol (37), such as by adding sodium borohydride to a solution of m. -2-nitrocinnarnaldehyde and cerium (III) chloride in methanol. The free hydroxyl group is then protected (eg. by means of tert-butyldimethylchlorosilane and imidazole in DMF) before being reduced to the protected aniline derivative (39). The latter is then reacted with a glycine derivative of the formula Q'-gly-OH (in which Q ¹ represents a suitable protecting group) to form compound (40). After reaction with sodium hydride, the product is then treated with a compound of formula in which Q ² represents a suitably protected derivative of the group R ⁸ , yielding the compound (41). This in turn is deprotected (eg. with tetrabutyl ammonium fluoride in THF) to form the 2-(3- hydroxypropyl)aniline derivative (42). This compound is then tosylated and the product (43) is treated with sodium hydride to form the benzodiazonine (44). Compound (45) may be obtained by catalytic hydrogenation or treatment of (44) with

trifluoroacetic acid, and the ring nitrogen atom may then be functionalised by reaction with an isocyanate of the formula R ¹⁶ NCO.

Figure 12 provides an alternative route to compounds of the invention in which X is H. The aniline derivative (47) is protected (eg. with di-tert-butyldicarbonate), and then reacted with n-butyl lithium and allyl bromide to form compound (49). This is then oxidised (eg. by treatment with ozone, followed by sodium borohydride) to form the alcohol (50). Protection of the free hydroxyl group and deprotection of the amino group gives the aniline derivative (52). This compound is then reacted with the glycine derivative Q'-gly-OH, and the product (53) is treated with sodium hydride and then with a compound of formula Q ² CH ₂ Br. After appropriate deprotection (55) and tosylation (56), the benzodiazonine compounds of the invention are obtained by steps analogous to those shown in Figure 11.

In a further aspect, therefore, the invention also provides a method of preparing a compound according to formula (I) above, said method including the step of reacting a compound of the formula

with an oxidant such as ozone to form a compound of the formula

Also provided is a method of preparing a compound according to formula (I) above in which X is H and Y is -OH, said method comprising reducing a compound of the

formula

The invention additionally provides a method of preparing a compound according to formula (I) above in which X is H and Y is -CH ₃ , said method comprising reducing a compound of the formula

Further provided is a method of preparing a compound according to formula (I) above wherein X and Y together form a methylene group, said method comprising the step of reacting a compound of formula

with μ-chloro-μ-methylene-[bis(cyclopentadienyl)titanium]dimeth ylaluminium.

In a still further aspect, the invention provides a method of preparing a compound according to formula I above, said method comprising the step of reacting a compound of the formula

with an isocyanate of the formula R ¹⁶ NCO or a carboxylic acid of the formula R ⁴ COOH.

Pharmaceutically acceptable salts of the acidic or basic compounds of the invention can of course be made by conventional procedures, such as by reacting the free base or acid with at least a stoichiometric amount of the desired salt-forming acid or base.

The compounds of the invention can be administered by oral or parenteral routes, including intravenous, intramuscular, intraperitoneal, subcutaneous, rectal and topical administration.

For oral administration, the compounds of the invention will generally be provided in the form of tablets or capsules or as an aqueous solution or suspension.

Tablets for oral use may include the active ingredient mixed with pharmaceutically acceptable excipients such as inert diluents, disintegrating agents, binding agents, lubricating agents, sweetening agents, flavouring agents, colouring agents and preservatives. Suitable inert diluents include sodium and calcium carbonate, sodium and calcium phosphate, and lactose, while corn starch and alginic acid are suitable disintegrating agents. Binding agents may include starch and gelatin, while the lubricating agent, if present, will generally be magnesium stearate, stearic acid or talc. If desired, the tablets may be coated with a material such as glyceryl monostearate or glyceryl distearate, to delay absoφtion in the gastrointestinal tract.

Capsules for oral use include hard gelatin capsules in which the active ingredient is mixed with a solid diluent, and soft gelatin capsules wherein the active ingredient is

mixed with water or an oil such as peanut oil, liquid paraffin or olive oil.

For intramuscular, intraperitoneal, subcutaneous and intravenous use, the compounds of the invention will generally be provided in sterile aqueous solutions or suspensions, buffered to an appropriate pH and isotonicity. Suitable aqueous vehicles include Ringer's solution and isotonic sodium chloride. Aqueous suspensions according to the invention may include suspending agents such as cellulose derivatives, sodium alginate, polyvinyl-pyrrolidone and gum tragacanth, and a wetting agent such as lecithin. Suitable preservatives for aqueous suspensions include ethyl and n-propyl p- hydroxybenzoate.

Effective doses of the compounds of the present invention may be ascertained by conventional methods. The specific dosage level required for any particular patient will depend on a number of factors, including the severity of the condition being treated, the route of administration and the weight of the patient. In general, however, the daily dose (whether administered as a single dose or as divided doses) will be in the range 0.001 to 5000 mg per day, more usually from 1 to 1000 mg per day, and most usually from lo to 200 mg per day. Expressed as dosage per unit body weight, a typical dose will be between 0.01 μg/kg and 50 mg/kg, especially between 10 μg/kg and 10 mg/kg, eg. between 100 μg/kg and 2 mg/kg.

The compounds of the following examples were prepared by the synthetic routes outlined in Figures 1 to 12. The structures of the title compounds are set out below:

Ex.57

Example 1 Preparation o f l -tert-b utyl ox ycarbon yl m eth y l -4 -(3- methylphenyl)carbamyl-2,7-dioxo-2, 3,4,5, 6,7-hexahydro-lH-l,4-benzodiazonine

a. 2-benzyloxycarbonyl-l,2,3,4-tetrahydro-9H-pyrido[3,4-b]indol e

Benzyl chloroformate (1.8 ml, 12.6 mmol) was added to a solution of 1,2,3,4- tetrahydro-9H-pyrido[3,4-b]indole (1.72 g, 10.0 mmol) and sodium bicarbonate (1.85 g, 22.0 mmol) in dioxan (50 ml) at room temperature. The mixture was stirred at room temperature for 16 hours, concentrated in vacuo and the residue dissolved in water (50 ml). The aqueous mixture was extracted with chloroform (3 x 50 ml), and the combined extracts dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purified by chromatography on silica gel with hexane- ethyl acetate (3:2) as eluant. (3.07 g, 100%).

b. 2-benzyloxycarbonyl-9-tert-butyloxycarbonylmethyl- 1 ,2,3, 4-tetrahydro-9H- pyrido[3,4-b]indole

A solution of 2-benzyloxycarbonyl-l,2,3,4-tetrahydro-9H-pyrido[3,4-b]indol e (3.06 g, 10.0 mmol) in dry DMF (30 ml) was added dropwise to a slurry of sodium hydride (60% dispersion in oil/ 480 mg, 12.0 mmol) in dry DMF (20 ml) under nitrogen at room temperature. The reaction mixture was stirred for one hour at room temperature to which was added dropwise tert-butyl bromoacetate (1.48 ml, 10.0 mmol). The reaction was stirred for a further two hours, diluted with ethyl acetate (100 ml), washed with brine (2 x 100 ml) and dried (MgSO ). Filtration and evaporation of the

solvent gave the crude product which was purified by chromatography on silica gel with ethyl acetate-hexane (2:5) as eluant. (3.28 g, 78%).

c. 9-tert-butyloxycarbonylmethyl-l ,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole

2-Benzyloxycarbonyl-9-tert-butyloxycarbonylmethyl- 1 ,2,3,4- tetrahydro-9H-pyrido- [3,4-b]indole (3.28 g, 7.81 mmol) was stirred under an atmosphere of hydrogen in the presence of 10% palladium on charcoal (500 mg) in methanol (30 ml) at room temperature for two hours. The reaction mixture was filtered through a pad of celite and evaporated to dryness affording the product. (2.14 g, 96%).

d. 9-tert-butyloxycarbonylmethyl-2-(3-methylphenyl)carbamyl-l ,2,3,4-tetrahydro- 9H-pyrido[3 ,4-b]indole

A solution of 9-tert-butyloxycarbonylmethyl-l,2,3,4-tetrahydro-9H-pyrido [3,4-b]- indole (3.56 g, 12.0 mmol) and 3-methylphenylisocyanate (1.60 ml, 12.4 mmol) was stirred in dioxan (40 ml) at room temperature for 4 hours. Evaporation of the solvent and chromatography on silica gel with ethyl acetate-hexane (1:3) as eluant gave the product. (3.29 g, 65%).

e. l -tert-butyloxycarbonylmethyl-4-(3-methylphenyl)carbarnyl-2,7 -dioxo- 2,3,4,5, 6, 7-hexahydro-lH-l ,4-benzodiazonine

Ozone was bubbled through a solution of 9-tert-butyloxycarbonylmethyl-2-(3-methyl- phenyl)carbamyl-l ,2,3,4-tetrahydro-9Η-pyrido[3,4-b]indole (2.99 g, 7.14 mmol) in methanol (35 ml) at -78 X until a blue colour persisted. Nitrogen was then bubbled through the solution until clear, followed by the addition of dimethyl sulphide (5.0 ml, 68.1 mmol). The solution was allowed to warm to room temperature and stirring continued for a further two hours, followed by evaporation to dryness. The crude product was purified by chromatography on silica gel with ethyl acetate-hexane (1 : 1 to 2: 1 ) as eluant. ( 1.79 g, 56%).

(CDC1,) δ _H 1.53 (9H, s), 2.33 (3H, s), 2.75 and 4.74 (2H, 2 x m), 3.0 (2H, m), 3.35 and 4.16 (2H, 2 x d, J = 15Hz), 3.69 and 4.83 (2H, 2 x d, J= 17Hz), 6.82 (IH, m), 7.16-7.77 (7H, m), 9.24 (IH, bs).

Found: C, 66.52; H, 6.68; N, 9.45. C_ ₅ H ₂₉ N ₃ O ₅ requires C, 66.50; H, 6.47; N, 9.31 %

Example 2 Preparation of l-tert-butyloxycarbonylmethyl-4-(3,4-dichlorophenyl)- carbamyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazoni ne

The compound was prepared by an identical method to that used in the preparation of example 1 except that 3,4-dichlorophenylisocyanate was used in step d in place of 3- methylphenylisocyanate.

(CDCl ₃ )δ _H 1.54 (9H, s), 2.75 and 4.70 (2H, 2 x m), 3.0 (2H, m), 3.45 and 4.14 (2H, 2 x d, J = 15Hz), 3.69 and 4.86 (2H, 2 x d, J= 17Hz), 7.30 (2H, m), 7.48-7.76 (5H, m), 9.54 (IH, s).

Found: C, 56.80; H, 5.05; N 8.42. requires C, 56.90; H, 4.98; N, 8.30%

Example 3 Preparation of l-benzyl-4-(3-methylphenyl)carbamyl-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

a. 2-butyloxycarbonyl-l,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole

A solution of 1,2,3, 4-tetrahydro-9H-pyrido[3,4-b]indole(8.96 g, 52 mmol) and di-tert- butyl dicarbonate (1 1.4 g, 52 mmol) in dioxan (180 ml) was stirred at room temperature for 17 hours. The solvent was evaporated to afford the crude product which was then recrystallised from dichloromethane-hexane. (13.9 g, 98%).

b. 9-benzyl-2-tert-butyloxycarbonyl-l ,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole

A solution of 2-tert-butyloxycarbonyl- 1,2, 3 ,4-tetrahydro-9H-pyrido[3 , 4-b]indole(2.96 g, 10.9 mmol) in dry DMF (15 ml) was added dropwise to a slurry of sodium hydride (60% dispersion in oil/ 479 mg, 12.0 mmol) in dry DMF (15 ml) maintained under nitrogen at room temperature. After stirring for 45 minutes at room temperature benzyl bromide (1.3 ml, 10.9 mmol) was added dropwise. The reaction was stirred for a further 2 hours, diluted with ethyl acetate (75 ml), washed with brine (2 x 80 ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purified by chromatography on silica gel with ethyl acetate-hexane (2:7) as eluant. (3.68 g, 92%).

c. 9-benzyl-l,2,3,4-tetrahydro-9H-ρyrido[3,4-b]indole

A solution of 9-benzyl-2-tert-butyloxycarbonyl-l,2,3,4-tetrahydro-9H-pyrid o[3,4-b]- indole (3.66 g, 10.1 mmol) in chloroform (50 ml) was stirred with trifluoroacetic acid (20 ml) at room temperature for 2 hours. The mixture was evaporated to dryness and the residue partitioned between chloroform and saturated potassium carbonate solution (150ml/ 1:2). The organic layer was separated and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product. (2.66 g, 100%).

d. 9-benzyl-2-(3-methylphenyl)carbamyl- 1 ,2,3, 4-tetrahydro-9H-pyrido[3,4-b]- indole

A solution of 9-benzyl-l ,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole(2.66 g, 10.1 mmol) and 3-methylphenylisocyanate (1.42 ml, 11.0 mmol) was stirred in dioxan (40 ml) at room temperature for 4 hours. Evaporation of the solvent and chromatography on silica gel with ethyl acetate-hexane (2:3) as eluant gave the product. (3.04 g, 76%).

e. l-benzyl-4-(3-methylphenyl)carbamyl-2,7-dioxo-2,3,4,5,6,7-he xahydro-lH-

1 ,4-benzodiazonιne

Ozone was bubbled through a solution of 9-benzyl-2-(3-methylphenyl)carbamyl- l ,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole (2.98 g, 7.54 mmol) in methanol (40 ml) at -78 °C until a blue colour persisted. Nitrogen was then bubbled through the solution until clear, followed by the addition of dimethyl sulphide (5.0 ml, 68.1 mmol). The solution was allowed to warm to room temperature and stirring continued for a further 2 hours, followed by evaporation to dryness. The crude product was purified by chromatography on silica gel with ethyl acetate-hexane (3:2) as eluant. (2.0 g, 62%).

(CDC1 ₃ ) δ _H 2.34 (3H, s), 2.70 and 4.75 (2H, 2 x m), 3.0 (2H, m), 3.51 and 4.21 (2H, 2 x d, J = 15Hz), 4.05 and 5.77 (2H, 2 x d, J= 14Hz), 6.80 (2H, m), 7.18-7.50 (11H, m), 9.50 (IH, s).

(CDCI ₃ ) δ _c 21.4, 44.8, 47.5, 52.9, 54.4, 116.7, 120.2, 123.4, 125.8, 127.8, 128.6, 129.0, 129.1 , 129.4, 131.0, 136.0, 138.0, 138.5, 139.0, 140.0, 155.0, 170.0, 204.3.

Found: C, 72.81; H, 5.94; N, 9.85. requires C, 73.05; H, 5.89; N, 9.83%

Example 4 Preparation of l-ethoxycarbonylmethyl-4-(3-methylphenyl)carbamyl-2,7- dioxo-2 , 3 ,4 , 5 , 6, 7-hexahydro- 1 H- 1 , 4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 3 except that ethylbromoacetate was used in step b in place of benzyl bromide.

(CDClj) δ _H 1.34 (3H, t), 2.33 (3H, s), 2.76 and 4.76 (2H, 2 x m), 3.03 (2H, m), 3.41 and 4.22 (2H, 2 x d, J = 15Hz), 3.85 and 4.97 (2H, 2 x d, J = 17Hz), 4.30 (2H, m), 6.82 (I H, m), 7.2 (3H, m), 7.48-7.61 (3H, m), 7.75-7.89 (IH, m), 9.19 (IH, s).

Found: C, 56.60; H, 6.49; N, 8.71. 3.5 H ₂ O requires C, 56.70; H, 6.58; N, 8.64%

Example 5 Preparation of 4-(3-methylphenyl)carbamyl-2,7-dioxo-2, 3,4,5, 6,7- hexahydro- IH- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 3 except that l,2,3,4-tetrahydro-9Η-pyrido[3,4-b]indole was used in step d in place of 9-benzyl-l,2,3,4-tetrahydro-9H-pyrido[3,4-b]-indole.

(CDC1 ₃ ) δ _H 2.37 (3H, s), 3.0 (2H, t, J=6Hz), 3.74 (4H, bs), 6.85 (IH, m), 7.17-7.59 (8H, m), 9.12 (lH, s).

Found: C, 67.31 ; H, 5.73; N, 12.22. C ₁₉ H ₁₉ N ₃ O ₃ requires C, 67.64; H, 5.68; N, 12.46%

Example 6 Preparation of 4-(3-methylphenyl)carbamyl-2,7-dioxo-l-pyrrolidinoyl- methyl-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

a. l-carboxymethyl-4-(3-methylphenyl)carbamyl-2,7-dioxo-2,3,4,5 ,6,7-hexahydro- 1H-1 ,4-benzodiazonine

A solution of l-tert-butyloxycarbonyl-4-(3-methylphenyl)carbamyl-2,7-dioxo - 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine (452 mg, 1.0 mmol) in chloroform (4 ml) was stirred with trifluoroacetic acid (4 ml) at room temperature for 2 hours. The mixture was evapoarted to dryness and the residue dissolved in chloroform (50 ml), washed with brine (3 x 40 ml), and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product. (393 mg, 99%).

b. 4-(3-methylphenyl)carbamyl-2,7-dioxo-l-pyrrolidinoylmethyl-2 ,3,4,5,6,7-

hexahydro- 1 H- 1 ,4-benzodiazonine

Pyrrolidine (117 μl, 1.41 mmol) was added to a solution of l-carboxymethyl-4-(3- methylphenyl)carbamyl-2 , 7-dioxo-2 , 3 ,4 ,5 , 6, 7-hexahydro- 1 H- 1 , 4-benzodiazonin^373 mg, 0.94 mmol), EDC (181 g, 0.94 mmol) and ΗOBt (127 mg, 0.94 mmol) in DMF (3 ml) at room temperature. The reaction mixture was stirred at room temperature for 28 hours, diluted with water (50 ml), and extracted with ethyl acetate (50 ml). The organic extract was washed with 10% citric acid solution (50 ml), brine (2 x 50 ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purified by chromatography on silica gel with ethyl acetate as eluant. (138 mg, 34%).

(CDClj) δ _Η 1.86-2.05 (4H, m), 2.31 (3H, s), 2.80 and 4.75 (2H, 2 x m), 3.0 (2H, ), 3.32-3.78 (6H, m), 4.17 and 4.96 (2H, 2 x d, J = 16Hz), 6.80 (IH, ), 7.15-7.58 (6H, ), 8.02 (IH, m), 9.32 (IH, s).

Found: C, 66.70; H, 6.41; N, 12.60. requires C, 66.90; H, 6.29; N,

12.50%

Example 7 Preparation of 1 -benzyl -7-hydroxy-4-(3-methylphenyl)carbamyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine (isomer 1)

Sodium borohydride (19 mg, 0.5 mmol) was added in a single portion to a solution of l-benzyl-4-(3-methylphenyl)carbamyl-2,7-dioxo-2,3,4,5,6,7-he xahydro-lH-l,4- benzodiazonine (213 mg, 0.5 mmol) in methanol (5 ml) at room temperature. The reaction mixture was stirred at room temperature for 10 minutes followed by the addition of saturated ammonium chloride solution (40 ml). The mixture was extracted with chloroform (3 x 40 ml), and the combined extracts dried over magnesium sulphate. Filtration and evaporation of the solvent gave the crude product. The compound was obtained by isolation of the less polar component by chromatography on silica gel, with ethyl acetate-hexane (1 : 1) as eluant. (104 mg,

48%)

(CDC1 ₃ ) δ _H 1.50 (2H, m), 1.79 (IH, dt, J= 14, 3Hz), 2.33-2.42 (4H, m), 3.22 (IH, d, J = 15Hz), 4.08-4.33 (4H, m), 5.84 (IH, d, J= 14Hz), 6.87 (IH, ), 7.12-7.49 (12H, m), 9.40 (IH, s).

Found: C, 71.31; H, 6.35; N, 9.65. C^N . 0.5 H ₂ O requires C, 71.21 ; H, 6.44; N, 9.58%

Example 8 Preparation of l-benzyl-7-hydroxy-4-(3-methylphenyl)carbamyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine (isomer 2)

The compound was prepared by an identical route to that used in the preparation of example 7 except that the more polar component was isolated by chromatography. (78 mg, 36%)

(CDCI ₃ ) δ _Η 1.50 (2H, m), 1.79 (IH, dt, J = 14, 3Hz), 2.33-2.42 (4H, m), 3.22 (IH, d, J = 15Hz), 4.08-4.33 (4H, ), 5.84 (IH, d, J = 14Hz), 6.87 (IH, m), 7.12-7.49 (12H, ), 9.40 (IH, s).

Found: C, 72.39; H, 6.41; N, 9.50. C ₂₆ l ₂₇ N ₃ 0 ₃ requires C, 72.71 ; H, 6.34; N, 9.78%

Example 9 Preparation of l-benzyl-7-methylene-4-(3-methylphenyl)carbamyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

a. l-benzyl-4-tert-butyloxycarbonyl-2,7-dioxo-2,3,4,5,6,7-hexah ydro-lH-l ,4- benzodiazonine

Ozone was bubbled through a solution of 9-benzyl-2-tert-butyloxycarbonyl-l ,2,3,4- tetrahydro-9H-pyrido[3,4-b]indole (6.0 g, 16.6 mmol) in methanol (90 ml) at -78"C until a blue colour persisted. Nitrogen was then bubbled through the solution until clear, followed by the addition of dimethyl sulphide (12.0 ml, 163 mmol). The solution was allowed to warm to room temperature and stirring continued for a further 2 hours, followed by evaporation to dryness. The crude product was purified by chromatography on silica gel with ethyl acetate-hexane (1: 1) as eluant. (6.0 g, 92%).

b. l-benzyl-4-tert-butyloxycarbonyI-7-methylene-2-oxo-2, 3,4,5, 6,7-hexahydro-lH- 1 ,4-benzodiazonine

μ-Chloro-μ-methylene-[bis(cyclopentadienyl)titanium]dim ethylaluminium (0.5M in toluene/15 ml, 7.5 mmol) was added to a solution of l-benzyl-4-tert-butyloxycarbonyl- 2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l ,4-b enzodiazonine (2.95 g, 7.5 mmol) in tetrahydrofuran (23 ml) at -5 ^* C. The resultant suspension was stirred at -5 ^* C for 15 minutes then allowed to warm to room temperature. Stirring was continued for a further 30 minutes followed by the addition of ethyl acetate (50 ml) and the mixture was washed with 0.2M sodium hydroxide solution (1.5 ml), and dried (MgSO ₄ ). The mixture was filtered through a pad of celite and evaporated to dryness. The crude product was purified by chromatography on silica gel with ethyl acetate-hexane (1:3) as eluant. (981 mg, 33%).

c. l-benzyl-7-methylene-2-oxo-2,3,4,5,6,7-hexahydro-lH-l,4-benz odiazonine

A solution of l-benzyl-4-tert-butyloxycarbonyl-7-methylene-2-oxo-2,3,4,5,6 ,7- hexahydro-lH-l ,4-benzodiazonine (154 mg, 0.39 mmol) in chloroform (2 ml) was stirred with trifluoroacetic acid (1 ml) at room temperature for 45 minutes. The mixture was evapoarted to dryness and the residue partitioned between chloroform and saturated potassium carbonate solution (60 ml/ 1 :2). The organic layer was separated and dried (MgSO ₄ ). Filtration and evapoartion of the solvent gave the product. (94 mg, 83%).

d. 1 -benzyl -7-methylene-4-(3-methylphenyl)carbamyl-2-oxo-2, 3, 4, 5,6,7- hexahydro- IH- 1 ,4-benzodiazonine

A solution of l-benzyl-7-methylene-2-oxo-2,3,4,5,6,7-hexahydro-lH-l ,4- benzodiazonine (94 mg, 0.32 mmol) and 3-methylphenylisocyanate (42 μl, 0.33 mmol) was stirred in dichloromethane (2 ml) at room temperature for 3 hours. Evaporation of the solvent and chromatography on silica gel with ethyl acetate-hexane as eluant (1: 1) gave the product. (131 mg, 96%).

(CDC1 ₃ ) δ _Η 2.25 and 2.80 (IH, 2 x m), 2.34 (3H, s), 2.66 and 4.54 (2H, 2 x ), 3.30 and 4.21 (2H, 2 x d, J = 15Hz), 4.02 and 5.60 (2H, 2 x d, J = 14Hz), 4.81 (IH, s), 5.34 (IH, s), 6.93 (IH, m), 7.17 (IH, m), 7.25-7.41 (11H, m), 9.62 (IH, bs).

Found: C, 75.97; H, 6.66; N, 10.01. C ₂₇ H ₂₇ N ₃ O ₂ requires C, 76.21; H, 6.40; N, 9.87%

Example 10 l-benzyl-7-methyl-4-(3-methylphenyl)carbamyl-2-oxo-2,3,4,5,6 ,7- hexahydro- IH- 1 ,4-benzodiazonine

a. l-benzyl-4-tert-butyloxycarbonyl-7-methyl-2-oxo-2, 3,4,5, 6,7-hexahydro-lH- 1 ,4-benzodiazonine

l-Benzyl-4-tert-butyloxycarbonyl-7-methylene-2-oxo-2,3,4, 5,6,7-hexahydro-lH-l ,4- benzodiazonine (160 mg, 0.41 mmol) was stirred under an atmosphere of hydrogen in the presence of 10% palladium on charcoal (20 mg) in dioxan (5 ml) at room temperature for 20 hours. The reaction mixture was filtered through a pad of celite and evaporated to dryness affording the product. (160 mg, 100%).

b. l-benzyl-7-methyl-2-oxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

Asolutionofl-benzyl-4-tert-butyloxycarbonyl-7-methyl-2-ox o-2,3,4,5,6,7-hexahydro-

lH-l ,4-benzodiazonine (160 mg, 0.41 mmol) in chloroform (2 ml) was stirred with trifluoroacetic acid (3 ml) at room temperature for 30 minutes. The mixture was evaporated to dryness and the residue partitioned between chloroform and saturated potassium carbonate solution (30 ml/ 1:2). The organic layer was separated and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product. (98 mg, 81 %).

c. 1 -benzyl-7-methyl-4-(3-rnethylphenyl)carbamyI-2-oxo-2, 3 ,4,5 , 6, 7-hexahydro- lH-l ,4-benzodiazonine

A solution of l-benzyl-7-methyl-2-oxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine (96 mg, 0.33 mmol) and 3-methylphenylisocyanate (47 μl, 0.36 mmol) was stirred in dioxan (2 ml) at room temperature for 2 hours. Evaporation of the solvent and chromatography on silica gel with ethyl acetate-hexane (1:2) as eluant gave the product. (102 mg, 72%).

(CDClj) δ _Η 0.56 (3H, d, J=7Hz), 1.35 and 1.88 (2H, 2 x ), 2.08 and 2.64 (2H, 2 x m), 2.36 (3H, s), 3.27 and 4.22 (2H, 2 x d, J = 15Hz), 4.28 (IH, ), 4.62 and 5.30 (2H, 2 x d, J = 14Hz), 6.83 (IH, m), 7.10-7.41 (12H, ), 9.51 (IH, s).

Found: C, 75.80; H, 6.89; N, 9.68. C ₂₇ H ₂₉ N ₃ O ₂ requires C, 75.90; H, 6.84; N, 9.84%

Example 11 Preparation of (3R,5S) 4-acetyl-3-[(l-adamantyl)methyl]-l-benzyl-2,7- dioxo-2, 3,4,5, 6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate

a. (lR,3S)-benzyl l-(l-adamantyl)methyl-l ,2,3,4-tetrahydro-9Η-pyrido[3,4-b]- indole-3-carboxylate

Trifluoroacetic acid (270 μl, 3.5 mmol) was added to a solution of L-tryptophan benzyl ester (10.23 g, 34.8 mmol) and 1-adamantylacetaldehyde (6.2 g, 34.8 mmol) in dry DCM (300 ml) wth 3A molecular sieves (46.5 g) at -10°C. The reaction mixture was allowed to warm to room temperature and stirred for 7 hours. The

mixture was cooled to 0°C trifluoroacetic acid (5.6 ml, 72.7 mmol) added, and stirring continued at room temperature for 16 hours. The reaction mixture was filtered, washed successively with saturated NaHCO ₃ solution (200 ml), brine (2 x 200 ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product. The compound was obtained by isolation of the more polar component by flash chromatography on silica gel with ethyl acetate-DCM (1:40) as eluant. (6.2g, 39%)

b. (lR,3S)-benzyl2-acetyl-l-(l-adamantyl)methyl-l,2,3,4-tetrahy dro-9H-pyrido- [3,4-b]indole-3-carboxylate

Acetyl chloride (1.2 ml, 16.9 mmol) was added to a solution of (lR,3S)-benzyl 1-(1- adamantyl)methyl- 1 ,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole-3-carboxylate (6.24 g, 13.7 mmol) and triethylamine (1.9 ml, 13.6 mmol) with DMAP (30 mg) in dry DCM (120 ml) at -20 "C under nitrogen. The solution was allowed to warm to room temperature and after stirring for a further 2 hours was washed successively with 10% citric acid solution (100 ml), brine (2 x 100 ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which on trituration with ethyl acetate afforded a white amorphous solid which was isolated by filtration and dried. (6.3 g, 93%).

c. (lR,3S)-benzyl 2-acetyl-l-(l-adamantyl)meώyl-9-benzyl-l,2,3,4-tetrahydro-9 H- pyrido[3,4-b]indole-3-carboxylate

A solution of (lR,3S)-benzyl 2-acetyl-l-(l-adamantyl)methyl-l,2,3,4-tetrahydro-9H- pyrido[3,4-b]indole-3-carboxylate (6.3 g, 12.7 mmol) in dry DMF (50 ml) was added dropwise to a slurry of sodium hydride (60% dispersion in oil/ 0.56 g, 14 mmol) in dry DMF (20 ml) under nitrogen at room temperature. The reaction mixture was stirred for 15 minutes at room temperature to which was added dropwise a solution of benzyl bromide (1.6 ml, 13.5 mmol) in DMF (10 ml). The reaction was stirred for a further one hour, diluted with ethyl acetate (150 ml), washed successively with 2N HCl (150 ml), brine (3 x 150 ml) and dried (MgSO ₄ ). Filtration and evaporation

of the solvent gave the product as a yellow foam which was used without further purification. (7.45 g, 100%).

d. (3R,5S)-benzyl 4-acetyl-3-[(l-adamantyl)methyI]-l-benzyl-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate

Ozone was bubbled through a solution of (lR,3S)-benzyl 2-acetyl-l-(l-adamantyl)- methyl-9-benzyl-l ,2,3,4-tetrahydro-9Η-pyrido[3,4-b]indole-3-carboxylat 7.45g,12.7 mmol) in methanol (200 ml) at -78 ^* C until a blue colour persisted. Nitrogen was then bubbled through the solution until clear, followed by the addition of dimethyl sulphide (6.0 ml, 81.7 mmol). The solution was allowed to warm to room temperature and stirring continued for a further 2 hours, followed by evaporation to dryness. The crude product was purified by flash chromatography on silica gel with ethyl acetate- DCM (1 : 19) as eluant, affording the product as a colourless oil. (5.8 g, 72%).

e. (3R,5S)-4-acetyl-3-[(l-adamantyl)methyl]-l-benzyl-2,7-dioxo- 2, 3,4,5,6,7- hexahydro-lH-l,4-benzodiazonine-5-carboxylate

(3R,5S)-Benzyl 4-acetyl-3-[(l-adamantyl)methyl]-l-benzyl-2,7-dioxo-2,3,4,5, 6,7- hexahydro-lH-l,4-benzodiazonine-5-carboxylate (5.8 g, 9.2 mmol) was stirred under an atmosphere of'hydrogen in the presence of 10% palladium on charcoal (500 mg) in methanol-tetrahydrofuran (100 ml/ 1:1) at room temperature for one hour. The reaction mixture was filtered through a pad of celite and evaporated to dryness affording the product as a white amoφhous solid. (4.75 g, 96%).

(CDC1 ₃ ) δ _Η 1.20 (3H, s), 1.21-1.36 (4H, ), 1.53-1.69 (9H, m), 1.94 (3H, s), 2.60 (IH, dd), 3.00 (IH, dd), 3.89-4.05 (4H, m), 5.60 (IH, d), 6.75 (IH, d), 7.22-7.46 (8H, ).

[α] ^D = -82.0° (C = 1.0%, MeOH)

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 61.58; H, 7.68; N 5.69. C ₃₉ H ₅₃ N ₃ O ₁₀ . 2 H ₂ O requires C, 61.64; H, 7.56; N 5.53%

Example 12 Preparation of (3S,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7- dioxo-2 , 3 ,4 ,5 , 6,7-hexahydro- IH- 1 ,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that the less polar component, (lS,3S)-benzyl l-(l-adamantyl)- methyl-l,2,3,4-tetrahydro-9Η-pyrido[3,4-b]indole-3-carboxyl ate, was isolated by chromatography in step a and used in step b in place of (lR,3S)-benzyI 1-(1- adamantyl)methyl-l ,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole-3-carboxylate.

(CDClj) δ _H 1.19 (3H, s), 1.24-1.36 (4H, m), 1.44-1.62 (9H, m), 1.94 (3H, s), 2.63 (IH, dd), 3.00 (IH, dd), 3.90-4.06 (4H, m), 5.65 (IH, d), 6.78 (IH, d), 7.22-7.45 (8H, ).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.94; H, 7.60; N, 5.46. 2.5 H ₂ O requires C, 60.92; H, 7.60; N 5.47%

Example 13 Preparation of (3R,5S)-4-acetyl-3-[(l-adamantyl)methyl]-l-(3- methoxy)benzyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzod iazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that 3-methoxybenzyl bromide was used in step c in place of benzyl bromide.

(d ⁶ -DMSO) δ _Η 1.20 (3H, s), 1.34-1.37 (4H, m), 1.44-1.73 (9H, m), 1.93 (3H, s), 2.65 (IH, dd), 3.00 (I H, m), 3.76 (3H, s), 3.89 (IH, d), 3.97-4.07 (3H, m), 5.64

(IH, d), 6.83 (4H, m), 7.20 (2H,m), 7.44 (2H, m).

[a? = -97.0° (C = 1.0% , MeOH)

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 61.37; H, 7.55; N, 5.29. CwftjNjO,,. 1.5 H ₂ O requires C, 61.52; H,

7.49; N, 5.38%

Example 14 Preparation of (3R,5S)-4-acetyl-3-[(l-adamantyl)methyI]-l -(4- methoxy)benzyl-2,7-dioxo-2,3,4,5 ₎ 6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that 4-methoxybenzyl bromide was used in step c in place of benzyl bromide.

(CDClj) δ _Η 1.18 (3H, s), 1.36 (4H, m), 1.44-1.73 (9H, ), 1.94 (3H, s), 2.60 (IH, dd), 3.00 (IH, m), 3.84 (3H, s), 3.88 (IH, d), 3.97-4.03 (3H, m), 5.56 (IH, d), 6.74 (IH, d), 6.82 (2H, d), 7.15 (2H, d), 7.33-7.43 (3H, m).

[α] ^D = -104.0' (C = 0.99%, MeOH)

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.19; H, 7.37; N, 5.38. C ₄₀ H ₅ jN ₃ O _u . 2.5 H ₂ O requires C, 60.14; H,

7.57; N, 5.25%

Example 15 Preparation of (3R,5S)-4-acetyl-3-[(l-adamantyl)methyl]-l -(3- chloro)benzyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-l -l ,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that 3-chlorobenzyl bromide was used in step c in place of benzyl bromide.

(CDC1 ₃ ) δ _H 1.23 (3H, s), 1.36 (4H, m), 1.54-1.73 (9H, ), 1.96 (3H, s), 2.60 (IH, dd), 3.00 (IH, m), 3.88 (IH, d), 4.00 (3H, m), 5.65 (IH, d), 6.84 (IH, d), 7.08 (IH, d), 7.19-7.47 (6H, m).

[ ] ^D = -95.0' (C = 1.0%, MeOH)

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 61.49; H, 6.93; N 5.76. requires C, 61.77; H, 6.91 ; N, 5.54%

Example 16 Preparation of (3R,5S)-4-acetyl-3-[(l-adamantyl)methyl]-l-(4- chloro)benzyl-2 , 7-dioxo-2 , 3 , 4 , 5 , 6 , 7-hexahydro- 1 H- 1 ,4-benzodiazonine-5 -carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that 4-chlorobenzyl bromide was used in step c in place of benzyl bromide.

(d ⁶ -DMSO) δ _H 1.06 (4H, s), 1.26 (3H, d), 1.46 (3H, d), 1.53-1.65 (6H, m), 1.85 (3H, s), 2.40 (IH, dd), 2.75 (IH, ), 3.70 (IH, m), 4.00 (3H, m), 5.27 (IH, d), 7.13 (IH, d), 7.28 (2H, d), 7.37 (2H, d), 7.50 (3H, ).

[α] ^D = -116.0° (C = 1.0%, DMF)

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 58.19; H, 7.22; N 5.19. C ₃₉ H„C1N,O ₁₀ . 2.5 H ₂ O requires C, 58.31 ; H,

7.15; N, 5.23%

Example 17 Preparation of (3R,5S)-4-acetyl-3-[(l-adamantyl)methyl]-l-(3- amino)benzyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that 3-nitrobenzyl bromide was used in step c in place of benzyl bromide.

(d ⁶ -DMSO) δ _Η 1.05 (4H, s), 1.34 (3H, d), 1.52 (3H, d), 1.61 (6H, m), 1.89 (3H, s), 2.44 (IH, dd), 2.72 (IH, dd), 3.66-3.81 (3H, m), 4.00 (IH, d), 5.28 (IH, d), 6.34 (IH, d), 6.38 (lH,s), 6.45 (lH,d), 6.92 (IH, t), 7.03 (IH, d), 7.50 (3H, ).

[α] ^D = -116.0° (C = 1.0%, DMF)

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.89; H, 7.53; N, 7.42. C ₃₉ H ₅₄ N ₄ O _I0 . 1.5 H ₂ O requires C, 61.16; H, 7.50; N, 7.32%

Example 18 Preparation of (3R,5S)-methyl 4-acetyl-3-[(l-adamantyl)methyI]-l- benzyl-2, 7-dioxo-2 , 3 , 4 , 5 , 6, 7-hexahydro- 1 H- 1 ,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that L-tryptophan methyl ester was used in step a in place of L- tryptophan benzyl ester.

(CDCl,) δ _H 1. 18 (4H, s), 1.37 (3H, d), 1.54-1.74 (9H, m), 1.95 (3H, s), 2.61 (IH, dd), 3.01 (IH, dd), 3.70 (3H,s), 3.90 (IH, d), 3.94-4.06 (3H, m), 5.67 (IH, d), 6.78 (IH, d), 7.23-7.44 (8H, m).

[ ? = -103.3° (C = 0.91 %, MeOH)

Found: C, 60.89; H, 7.53; N, 7.42. C ₃₉ H _J4 N ₄ O ₁₀ . 1.5 H ₂ O requires C, 61.16; H, 7.50; N, 7.32%

Example 19 Preparation of (3R,5S)-4-acetyl-l-benzyl-3-(2,2-dimethylpropyl)-2,7- dioxo-2 , 3 ,4 ,5 , 6, 7-hexahydro- 1 H- 1 , 4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that 3,3-dimethylbutyraldehyde was used in step a in place of 1- adamantylacetaldehyde.

(d ⁶ -DMSO) δ _Η 0.84 (9H, s), 1.13 (3H, s), 1.35 (IH, d), 2.21 (IH, dd), 2.90 (IH, d), 3.38 (IH, dd), 3.87-3.96 (3H,m), 4.68 (IH, d), 5.48 (IH, d), 6.72 (IH, d), 6.94- 7.48 (8H, ).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 56.64; H, 7.63; N, 6.00. C ₃₃ H ₄₇ N ₃ O _I0 . 3.0 H ₂ O requires C, 56.56; H, 7.36; N, 5.94%

Example 20 (3R,5S)-3-<l-adamantyl)methyl-l-benzyl-4-benzyloxycarbony l-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that benzylchloroformate was used in step b in place of acetyl chloride.

(d ^ft -DMSO) δ _Η 1.02 (2H, d), 1.25 (4H, d), 1.38 (2H, d), 1.50 (4H, s), 1.64 (3H, s), 1.85 (IH, s), 2.19 (IH, m), 2.93 (I H, m), 3.75-3.95 (2H, m), 4.19 (2H, m), 4.30

and 4.62 (2H, ), 5.46 (IH, d), 6.74 (IH, d), 7.09-7.43 (8H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 66.33; H, 7.13; N, 5.18. C ₄₅ H _J7 N ₃ θ _π requires C, 66.24; H, 7.04; N, 5.15%

Example 21 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyI)methyl-l-methyl-2,7- dioxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that methyl iodide was used in step c in place of benzyl bromide.

(CDClj) δ _Η 1.19 (4H, s), 1.26 (3H, d), 1.56-1.74 (6H, m), 1.91 (3H, s), 2.60 (IH, m), 3.00 (IH, m), 3.22 (3H, s), 3.88-4.12 (3H, m), 7.34 (2H, ), 7.49 (IH, t), 7.58 (IH, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 58.42; H, 7.87; N 6.07. 1.5 H ₂ O requires C, 58.73; H, 7.77; N, 6.23%

Example 22 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5- carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-l H-l,4-benzodiazonine

a. (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-benzyloxyc arbonylmethyl- aminocarbonyl-2,7-dioxo-2, 3,4,5, 6,7-hexahydro-lH-l ,4-benzodiazonine

PyBroP (233 mg, 0.5 mmol) was added to a solution of (3R,5S)-4-acetyl-3-(l- adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5, 6,7-hexahydro-lH-l ,4-benzodiazonine-5- carboxylate (264 mg, 0.5 mmol), glycine benzyl ester p-toluenesulphonate (170 mg,

0.5 mmol) and diisopropylethylamine (260 μl, 1.5 mmol) in dry DCM (5 ml). The reaction mixture was stirred at room temperature for 18 hours, diluted with DCM (20 ml), washed successively with 2N HCl solution (25 ml), brine (25 ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product (350 mg), which was purified by flash chromatography on silica gel with ethyl acetate-DCM (3:7) as eluant, affording the product as a colourless oil. (190 mg, 55%).

b. (3R,5S)-4-acetyl-3-( l -adamantyl)methyl- l-benzyl-5-carboxymethyl- aminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzodi azonine

(3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-benzylo xycarbonylmethyl- aminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzodi azonine(190mg,0.28 mmol) was stirred under an atmosphere of hydrogen in the presence of 10% palladium on charcoal (50 mg) in methanol-tetrahydrofuran (20 ml/ 1: 1) at room temperature for one hour. The reaction mixture was filtered through a pad of celite and evaporated to dryness affording the product as a white amorphous solid. (154 mg, 92%).

(d ⁶ -DMSO) δ _Η 1.04 (3H, s), 1.27 (4H, d), 1.45-1.57 (8H, ), 1.86 (3H, s), 2.31 (IH, t), 2.89 (IH, dd), 3.62-3.75 (3H, m), 3.89-3.99 (3H, m), 5.35 (IH, d), 7.00 (IH, m), 7.21-7.30 (5H, m), 7.38 (IH, t), 7.50 (3H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.46; H, 7.57; N, 6.89. C ₄₁ H ₅₆ N ₄ O _n . 2.0 H ₂ O requires C, 60.28; H, 7.40; N, 6.86%

Example 23 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-(2- carboxy)ethylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-l H-l ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 22 except that /3-alanine benzyl ester was used in step a in place of glycine

benzyl ester p-toluenesulphonate.

(d ⁶ -DMSO) δ„ 1.04 (3H, s), 1.27 (4H, d), 1.45-1.57 (8H, m), 1.86 (3H, s), 2.31 (3H, m), 2.89 (IH, dd), 3.16-3.21 (3H, m), 3.61 (IH, m), 3.88-3.98 (3H, m), 5.35 (IH, d), 7.00 (IH, ), 7.06 (IH, t), 7.23-7.28 (5H, m), 7.49 (3H, s).

[α] ^D = -56.0° (C = 1.0%, MeOH)

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 59.19; H, 7.53; N, 6.47. C ₄₂ H ₅₈ N ₄ O„. 3.0 H ₂ O requires C, 59.42; H, 7.60; N, 6.60%

Example 24 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-[(lS)- carboxy]ethylaminocarbonyl-2 , 7-dioxo-2 ,3,4,5 , 6, 7-hexahydro- 1 H- 1 , 4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 22 except that L-alanine benzyl ester was used in step a in place of glycine benzyl ester p-toluenesulphonate.

(d ⁶ -DMSO) δ _Η 1.06 (3H, s), 1.19 (3H, d), 1.27 (4H, ), 1.31-1.62 (9H, m), 1.87 (3H, s), 2.40 (IH, t), 2.89 (IH, dd), 3.65 (IH, m), 3.87-4.01 (3H, m), 4.20 (IH, m), 5.38 (IH, d), 7.00 (IH, d), 7.11 (IH, d), 7.21-7.30 (5H, m), 7.49 (3H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.73; H, 7.61; N 6.84. C ₄₂ H ₅₈ N ₄ O _M . 2.0 H ₂ O requires C, 60.71; H, 7.52; N, 6.74%

Example 25 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-[(lR)-

carboxy]ethylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-l H-l ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 22 except that D-alanine benzyl ester was used in step a in place of glycine benzyl ester p-toluenesulphonate.

(d ⁶ -DMSO) δ _Η 1.06 (3H, s), 1.24-1.27 (7H, m), 1.31-1.62 (9H, ), 1.86 (3H, s), 2.40 (IH, t), 3.00 (IH, dd), 3.62 (IH, m), 3.86-3.99 (3H, m), 4.06 (IH, m), 5.38 (IH, d), 7.00 (IH, d), 7.22-7.30 (5H, m), 7.41 (IH, d), 7.49 (3H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 59.22; H, 7.60; N 6.74. C ₄₂ H ₅₈ N ₄ O„. 3.0 H ₂ O requires C, 59.42; H, 7.60; N, 6.60%

Example 26 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-(l- carboxy-l-methyl)ethylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-he xahydro-lH-l ,4- benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 22 except that aminoisobutyric acid benzyl ester was used in step a in place of glycine benzyl ester p-toluenesulphonate.

(d ⁶ -DMSO) δ _Η 1.07-1.36 (HH, m), 1.48-1.69 (12H, m), 1.80 (3H, m), 2.17 and 2.40 (IH, m), 2.65 and 2.95 (IH, ), 3.60 and 4.00 (IH, 2 x ), 4.20 (IH, dd), 4.25 and 4.35 (IH, 2 x m), 5.25 and 5.60 (2H, 2 x m), 6.25-6.94 (IH, 4 x m), 7.11 (IH, ), 7.26 (4H, s), 7.44-7.81 (4H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 61.68; H, 7.53; N, 6.44. C^H ₆₀ N ₄ O _u . 1.5 H ₂ O requires C, 61.78; H, 7.60; N, 6.70%

Example 27 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-[(2S)- carboxy-pyrrolidinyl]carbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydr o-lH-l,4-benzodiazonine (isomer 1)

The compound was prepared by an identical route to that used in the preparation of example 22 except that L-proline benzyl ester was used in step a in place of glycine benzyl ester p-toluenesulphonate, and the less polar component isolated by chromatography. The final compound was then prepared by an identical sequence to that used in the preparation of example 22.

(d ⁶ -DMSO) δ _Η 0.85 and 0.90 (1Η, 2 x d), 1.17 (2H, 2 x m), 1.31-1.39 (2H, ), 1.60 (8H, m), 1.80 (5H, m), 2.09 and 2.49 (2H, 2 x m), 3.00 (IH, m), 3.16-3.49 (5H, ), 3.87 (0.5H, m), 4.10-4.34 (2H, m), 4.95-5.30 (1.5, m), 5.45 and 5.69 (IH, 2 x m), 7.05 (2H, m), 7.25 (4H, s), 7.51-7.63 (3H, ).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 61.49; H, 7.64; N, 6.45. 2.0 H ₂ O requires C, 61.67; H,

7.53; N, 6.54%

Example 28 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyI)methyl-l-benzyl-5-[(2S)- carboxy-pyrrolidinyl]carbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydr o-lH-l,4-ber-zodiazonine (isomer 2)

The compound was prepared by an identical route to that used in the preparation of example 22 except that L-proline benzyl ester was used in step a in place of glycine benzyl ester p-toluenesulphonate, and the more polar component isolated by

chromatography. The final compound was then prepared by an identical sequence to that used in the preparation of example 22.

(d ⁶ -DMSO) δ _H 1.01 (IH, s), 1.12-1.35 (3H, 2 x d), 1.47-1.63 (10H, m), 1.73-1.89 (6H, m), 2.20 and 2.41 (IH, 2 x m), 2.49 and 3.00 (IH, 2 x m), 3.05-3.65 (5H, m), 3.70-4.27 (4H, m), 4.80 (0.5H, 2 x d), 5.27 (IH, 2 x d), 5.75 (0.5, 2 x d), 6.77 and 6.86 (IH, 2 x ), 7.19 (2H, s), 7.27 (3H, s), 7.41-7.54 (3H, m).

The compound was further characterised and tested as a N-methyl-D-glucamine salt.

Found: C, 61.41 ; H, 7.64; N, 6.55. C .H STA,. 2.0 H ₂ O requires C, 61.67; H, 7.53; N, 6.54%

Example 29 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5- carboxymethyl-(N-methyl)aminocarbonyl-2,7-dioxo-2,3,4,5,6,7- hexahydro-lH-l ,4- benzodiazonine (isomer 1)

The compound was prepared by an identical route to that used in the preparation of example 22 except that sarcosine benzyl ester was used in step a in place of glycine benzyl ester p-toluenesulphonate, and the less polar component isolated by chromatography. The final compound was then prepared by an identical sequence to that used in the preparation of example 22.

(d -DMSO) δ _H 1.02 (2H, s), 1.12-1.35 (5H, m), 1.46-1.62 (9H, m), 1.77-1.88 (3H, m), 2.15 and 2.40 (IH, 2 x t), 2.60-2.82 (3H, ), 3.04-3.16 (2H, 3 x s), 3.75-4.15 (4H, m), 4.40-4.95 (IH, 3 x m), 5.31 (IH, 2 x d), 6.77 and 6.86 (IH, 2 x m), 7.19 (2H, s), 7.28 (3H, s), 7.28-7.52 (3H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.66; H, 7.67; N, 6.84. C ₄₃ H, ₈ N ₄ O _n - 2.0 H ₂ O requires C, 60.71 ; H,

7.52; N, 6.74%

Example 30 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)rnethyl-l-benzyI-5- carboxymethyl-(N-methyl)aminocarbonyl-2,7-dioxo-2,3,4,5,6,7- hexahydro-lH-l,4- benzodiazonine (isomer 2)

The compound was prepared by an identical route to that used in the preparation of example 22 except that sarcosine benzyl ester was used in step a in place of glycine benzyl ester p-toluenesulphonate, and the more polar component isolated by chromatography. The final compound was then prepared by an identical sequence to that used in the preparation of example 22.

(d ⁶ -DMSO) δ _Η 1.16-1.35 (8H, 4 x s), 1.47-1.61 (10H, ), 1.91 (3H, 2 x s), 2.18 (2H, s), 2.63-2.77 (3H, 3 x s), 3.45-4.16 (3.5H, m), 4.36 (0.5H, m), 5.05-5.75 (IH, 4 x m), 7.08 (2H, m), 7.26 (4H, m), 7.52-7.64 (3H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 59.15; H, 7.63; N, 6.64. C ₄₂ H ₅₈ N ₄ O„. 3.0 H ₂ O requires C, 59.42; H, 7.60; N, 6.60%

Example 31 Preparationof(3R,5S)-4-acetyl-3-( 1 -adamantyl)methyl- 1 -benzyl-5-(3 ,5- dicarboxyphenyl)aminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydr o-lH- l ,4- benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 22 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyI-l-(4-methoxy)benzyl- 2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate and dibenzyl aniline-3,5-dicarboxylate were used in step a in place of (3R,5S)-4-acetyl-3-(l- adamantyl)methyl-l -benzyI-2,7-dioxo-2, 3,4,5, 6,7-hexahydro-lH-l,4-benzodiazonine-5-

carboxylate and glycine benzyl ester p-toluenesulphonate respectively.

(d ⁶ -DMSO) δ _H 1.12 (2H, d), 1.26-33 (3H, m), 1.53-1.61 (9H, m), 1.85 (3H, s), 2.35 (IH, s), 2.75 and 3.01 (IH, 2 x m), 3.71 (3H, s), 4.00 (2H, t), 4.95 and 5.05 (IH, 2 x m), 5.65 (2H, 2 x d), 6.83 (4H, m), 7.18-7.35 (4H, m), 8.17 (IH, s), 8.40 (2H, s), 9.40 (IH, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 55.67; H, 7.19; N, 5.99. C^H^O,,. 4.0 H ₂ O requires C, 55.78; H, 7.23; N, 5.91 %

Example 32 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)memyl-5-carboxymethyl- aminocarbonyl-l-methyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 22 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-methyl-2,7-dioxo- 2,3,4,5, 6, 7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- IH- 1 ,4-benzodiazonine-5-carboxylate.

(d ⁶ -DMSO) δ _Η 1.07 (3H, s), 1.30-1.38 (4H, m), 1.48-1.57 (3H, m), 1.62 (6H, s), 1.90 (3H, s), 2.40 (IH, t), 2.89 (IH, dd), 3.07 (3H, s), 3.53-3.67 (3H, m), 3.91-4.01 (2H, m), 7.36 (IH, t), 7.45 (IH, d), 7.52 (IH, t), 7.65 (2H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Example 33 Preparation of (R S)-3-(l-adamantyl)me yl-l-benzyl-4-(2-carboxy)ethyl- carbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

a. (R/S)-l-(l-adamantyl)methyl-l ,2,3,4-tetrahydro-9Η-pyrido[3,4-blindole

Trifluoroacetic acid (443 μl, 5.8 mmol) was added to a solution of tryptamine (5.76 g, 36 mmol) and 1-adamantylacetaldehyde (6.52 g, 36.6 mmol) in dry DCM (450 ml) wth 3 A molecular sieves (46.5 g) at 0°C. The reaction mixture was stirred at 0°C for 2 hours, followed by the addition of trifluoroacetic acid (5.76 ml, 74.8 mmol) then allowed to warm to room temperature and stirring continued for a further 16 hours. The resultant suspension was concentrated in vacuo, taken up in ethyl acetate (200 ml), filtered, washed successively with saturated NaHCO ₃ solution (200 ml), brine (2 x 200 ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product as an orange foam which was used without further purification. (10.95 g, 95%).

b. (R/S)-l-(l-adamantyl)memyl-2-(2-carboxyethyl)carbonyl-l ,2,3,4-tetrahydro-9H- pyrido[3,4-b]indole

A mixture of (R/S)-l-(l-adamantyl)methyl-l ,2,3,4-tetrahydro-9H-pyrido[3,4-b]indole (640 mg, 2.0 mmol) and succinic anhydride (250 mg, 2.5 mmol) was stirred in dioxan (5 ml) at room temperature for 17 hours. The white precipiate which had formed was isolated by filtration, washed with dioxan and dried. (640 mg, 76%).

c. (R/S)-l-(l-adamantyl)methyl-9-benzyl-2-(2-benzyloxycarbonyl) ethylcarbonyl- 1 ,2 ,3 ,4-tetrahydrό-9H-pyrido[3 ,4-b]indole

A solution of (R/S)-l-(l-adamantyI)methyl-2-(2-carboxyethyl)carbonyl)-l,2, 3,4- tetrahydro-9H-pyrido[3,4-b]indole (534 mg, 1.3 mmol) in dry DMF (8 ml) was added dropwise to a slurry of sodium hydride (60% dispersion in oil/115 mg, 2.9 mmol) in dry DMF (3 ml) under nitrogen at room temperature. The reaction mixture was stirred for 15 minutes at room temperature to which was added benzyl bromide (320 μl, 2.7 mmol). The reaction was stirred for a further 2 hours, diluted with ethyl acetate (25 ml) and washed successively with 2N HCl (25 ml), brine (3 x 20 ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product as a yellow oil which was purified by flash chromatography on silica gel with ethyl acetate-DCM- hexane (2:9:9) as eluant affording the product as a white solid. (306 mg, 39%).

d. (R/S)-3-(l-adamantyl)methyl]-l-benzyl-4-(2-benzyloxycarbonyl )ethylcarbonyl- 2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

Ozone was bubbled through a solution of (R S)-l-(l-adamantyl)methyl-9-benzyl-2-(2- benzyloxycarbonyl)ethylcarbonyl-l,2,3,4-tetrahydro-9Η-pyrid o[3,4-b]indole(300mg, 0.5 mmol) in methanol (40 ml) at -78°C until a blue colour persisted. Nitrogen was then bubbled through the solution until clear, followed by the addition of dimethyl sulphide (0.5 ml, 6.8 mmol). The solution was allowed to warm to room temperature and stirring continued for a further 2 hours, followed by evaporation to dryness. The crude product was purified by flash chromatography on silica gel with ethyl acetate- DCM (1:9) as eluant, affording the product as a colourless oil (200 mg, 64%)

e. (R S)-3-(l-adamantyl)methyl-l-benzyl-4-(2-carboxy)ethylcarbonyl )-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

(R/S)-3-(l-adamantyl)methyl-l-benzyl-4-(2-benzyloxycarbon yl)ethylcarbonyl)-2,7- dioxo-2, 3,4,5, 6,7-hexahydro-lH-l,4-benzodiazonine(200mg, 0.32 mmol) was stirred under an atmosphere of hydrogen in the presence of 10% palladium on charcoal (50 mg) in methanol-tetrahydrofuran (20 ml/ 1 : 1) at room temperature for one hour. The reaction mixture was filtered through a pad of celite and evaporated to dryness affording the product as a white amoφhous solid. (153 mg, 88%).

(d ⁶ -DMSO) δ _Η 0.60-0.98 (2H, m), 1.21-1.38 (4H, m), 1.50-1.62 (8H, m), 1.87-2.01 (5H, m), 2.02-2.32 (2H, ), 2.51-2.98 (2H, m), 3.65 (0.5H, m), 3.81-4.16 (4H, m), 4.55 (0.5H, m), 4.95 (0.5H, m), 5.20-5.40 (IH, m), 5.72 (IH, d), 6.83 and 6.95 (IH, 2 x d), 7.05-7.58 (8H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.41 ; H, 7.86; N 5.26. C ₄₀ H ₅ ,N ₃ O ₁₀ . 3.0 H ₂ O requires C, 60.67; H, 7.76; N 5.30%

Example 34 Preparation of (R S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 33 except that acetyl chloride was used in step b in place of succinic anhydride.

(CDC1 ₃ ) δ _Η 0.86 (IH, d), 1.14 (1.5H, s), 1.38 (3H, d), 1.59-1.75 (11H, m), 1.95 (3H, m), 2.45-2.79 (2H, m), 2.99-3.30 (1.5H, m), 3.45-3.80 (IH, m), 4.03 (IH, dd), 4.26 (0.5H, m), 5.05 (0.5H, m), 5.22 and 5.51 (IH, d), 6.78 and 6.98 (IH, 2 x d), 7.09-7.17 (2H, m), 7.27 (3H, m), 7.42-7.51 (2H, m), 7.71 and 7.80 (IH, d x 2).

Found: C, 77.03; H, 7.51; N, 5.65. ^NA requires C, 76.83; H, 7.49; N, 5.78%

Example 35 Preparation of (R S)-3-(l-adamantyl)methyl-l-(3-amino)benzyl~4- carboxymethylcarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l,4 -benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 33 except that malonic acid mono-4-nitrobenzyl ester was used in step b in place of succinic anhydride and 3-nitrobenzyl bromide subsequently used in place of benzyl bromide in step c.

(d ⁶ -DMSO) δ _Η 1.35-1.55 (15H, s), 1.72-1.79 (4H, m), 3.43-3.55 (IH, q), 4.07 (IH, m), 4.70 (2H, dd), 5.40 (2H, dd), 5.64 (IH, d), 6.16 (2H, d), 6.22 (IH, s), 6.43 (IH, d), 6.92 (IH, t), 7.38 (IH, t), 7.60 (2H, m), 8.22 (3H, d).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 62.09; H, 7.37; N 7.51. _J H _M ^O, _. . 1.0 H ₂ O requires C, 61.89; H, 7.46; N 7.40%

Example 36 Preparation of (3S,5R)-4-acetyl-3-(l-adamantyl)methyI-l-benzy1-5- carbox y methy lami nocarbony 1 -2 , 7-dioxo-2 ,3 ,4 , 5 , 6 , 7-hexahydro- 1 H- 1 ,4-benzodiazonine

a. (3S,5R)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4, 5,6,7- hexahydro-lH-1 ,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that D-tryptophan benzyl ester was used in step a in place of L- tryptophan benzyl ester.

b. (3S,5R)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5- carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-l H-l,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 22 except that (3S,5R)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- IH- 1 ,4-benzodiazonine-5 -carboxylate.

[α] ^D = +67.0° (C = 1.0%, MeOΗ)

(d ⁶ -DMSO) δ _Η 1.04 (3H, s), 1.27 (4H, d), 1.45-1.57(8H, m), 1.86 (3H, s), 2.31 (IH, t), 2.89 (IH, dd), 3.62-3.75 (3H, m), 3.89-3.99 (3H, m), 5.35 (IH, d), 7.00 (IH, m), 7.21-7.30 (5H, ), 7.38 (IH, t), 7.50 (3H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.42; H 7.32; N, 7.20. C _4I H ₅₆ N ₄ O _n .2H ₂ O requires C, 60.28; H, 7.40; N, 6.86%

Example 37 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-

methoxycarbonylmethylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hex ahydro-lH-l,4- benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 22 except that glycine methyl ester hydrochloride was used in step a place of glycine benzyl ester p-toluenesulphonate.

(CDC1 ₃ ) δ _Η 1.15 (3H, s), 1.40-1.74(13H, m), 1.74 (3H, s), 2.70 (IH, t), 3.09 (IH, dd), 3.76 (3H, m), 3.90 (IH, d), 4.00-4.10 (4H, m), 5.60 (IH, d), 6.30 (IH, t), 6.77 (IH, d), 7.23-7.45 (8H, m).

Found: C, 69.22; H 7.02; N, 6.76. C ₃₅ H _4I N ₃ θ ₆ .0.5H ₂ O requires C, 69.06; H, 6.95; N, 6.90%

Example 38 Preparation of (3 R , 5S) -4-acety 1 - 1 -benzy 1 -5 - carboxymethylaminocarbonyl-3-(3,3-dimethyI)propyl-2,7-dioxo- 2,3,4,5,6,7-hexahydro- 1H-1 ,4-benzodiazonine

a. (3R, 5S)-4-acetyl-l-benzyl-3-(3,3-dimethyl)propyl-2,7-dioxo-2, 3,4,5, 6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used in the preparation of example 11 except that 3,3-dimethylbutyraldehyde was used in step a in place of 1- adamantylacetaldehyde.

b. (3R,5S)-4-acetyl-l-benzyl-5-carboxymethylaminocarbonyl-3-(3, 3- dimethyl)propyl-2,7-dioxo-2, 3,4,5, 6,7-hexahydro-lH-l,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 22 except that (3R,5S)-4-acetyl-l-benzyl-3-(3,3-dimethyl)propyl-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step a in

place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- IH- 1 ,4-benzodiazonine-5-carboxylate.

(d ⁶ -DMSO) δ _Η 0.84 (9H, s), 1.05 (3H, s), 1.56 (IH, d), 2.48(1H, m), 2.90 (IH, dd), 3.61 (3H, m), 3.96 (3H, m), 5.43 (IH, d), 6.97 (IH, ), 7.12-7.47 (9H, m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 53.63; H 7.79; N, 6.85. 5H ₂ O requires C, 53.59; H, 7.74; N, 6.94%

Example 39 Preparation of (3R , 5 S) -4-acety 1 - 1 -benzy 1 -5 - carboxymethylaminocarbonyl-3-cycloheptylmethyl-2,7-dioxo-2, 3,4,5, 6,7-hexahydro- lH-l,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 38 except that (3R,5S)-4-acetyl-l-benzyl-3-cycloheptylmethyl-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step b in place of (3R,5S)-4-acetyl-l-benzyl-3-(3,3-dimethyl)propyl-2,7-dioxo-2 ,3,4,5,6,7- hexahydro- IH- 1 ,4-benzodiazonine-5-carboxylate.

(d ⁶ -DMSO) δ _Η 1.10 (3H, s), 1.26-1.62(13H, m), 2.45(1H, m), 3.07(1H, m), 3.92- 4.16(6H, ), 5.66(1H, d), 6.62 (IH, t), 6.73 (IH, d), 7.20-7.43 (8H, ).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 53.74; H 7.88; N, 6.72. C ₃₉ H ₅₆ N ₄ O _n - 5H ₂ O requires C, 54.16; H, 7.92;

N, 6.48%

Example 40 Preparation of ( 3 R , 5 S ) - 4 - ac e t y 1 - 1 - b e n z y 1 - 5 -

carboxymethylaminocarbonyl-3-cyclohexylmethyl-2,7-dioxo-2,3, 4,5,6,7-hexahydro- 1H- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 38 except that (3R,5S)-4-acetyl-l-benzyl-3-cyclohexylmethyl-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step b in place of (3R,5S)-4-acetyl-l-benzyl-3-(3,3-dimethyl)propyl-2,7-dioxo-2 ,3,4,5,6,7- hexahydro- IH- 1 ,4-benzodiazonine-5-carboxylate.

(d ⁶ -DMSO) δ _Η 0.90-1.74 (12H, ), 1.17(3H, s), 2.45(1H, m), 3.07(1H, m), 3.93- 4.15(6H, m), 5.66(1H, d), 6.62 (IH, t), 6.73 (IH, d), 7.20-7.43 (8H, ).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 52.97; H 7.65; N, 6.64. _S H _M NA,. 6.5H ₂ O requires C, 53.08; H, 7.85; N, 6.52%

Example 41 Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyI-5- methanesulphonamidocarboxymethylaminocarbonyl-2 , 7-dioxo-2 ,3 ,4 ,5 , 6, 7-hexahydro- 1H-1 ,4-benzodiazonine.

Methanesulphonamide (540mg, 5.7mmol) was added to a solution of (SR^S^-acetyl- S-O-adamanty methyl-l-benzyl-S-caiixwymemylam hexahydro-lH-l,4-benzodiazonine (310mg, 0.52mmol), EDC (109mg, 0.57mmol), 1- hydroxybenzotriazole (77mg, 0.57mmol), diisopropylethylamine (150 μl, 0.86mmol), and DMAP (6mg, 0.05mmol), in dry DCM (20ml) and the reaction mixture stirred at room temperature for 18 hours. The solution was diluted with DCM (30ml), washed successively with 10% citric acid solution (2 x 40ml), brine (2 x 40ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product as a yellow foam, which was purified by preparative reverse phase ΗPLC with acetoni tri le- water as eluant. (148mg, 43%)

R, = 16.8 min. (C ₁₈ , 55-70% MeCN-H ₂ O, over 20 mins with 0.1 %TFA)

(d ⁶ -DMSO) δ _H 1 -06 (3H, s), 1.27-1.64 (13H, ), 1.87 (3H,s), 2.40 (IH, dd), 2.90 (IH, dd), 3.21 (3H, s), 3.74 (2H, m), 3.87-4.00 (4H, m), 5.34 (IH, d), 7.00 (IH, ), 7.21-7.30 (5H, m), 7.42-7.53 (4H, m), 11.48 (IH, s).

The compound was further characterised and tested as the sodium salt.

Example 42 Preparationof4-benzyloxycarbonyl-l-tert-butyloxycarbonylmeth yl-2,7- dioxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 1 except that benzylchloroformate was used in step d in place of 3- methylphenylisocyanate.

(CDC1 ₃ ) δ _Η 1.47 (9H, s), 2.97-3.60 (3H, m), 3.81-4.45 (5H, m), 4.94 (2H,dd), 6.74 (2H,m), 7.15-7.70 (7H, m).

Found: C, 66.57; H 6.38; N, 6.23; C^N requires C, 66.36; H, 6.24; N, 6.19%

Example 43 Preparation of l -tert-butyloxycarbonyl -2 , 7-dioxo-4- phenox ycarbony 1 methy 1-2 ,3,4,5,6, 7-hexahydro- 1 H- 1 , 4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 1 except that phenylchloroformate was used in step d in place of 3- methylphenylisocyanate.

(CDCI ₃ ) δ _Η 1.47 (9H, s), 2.88 and 3.48 (IH, 2 x m), 3.05-3.30 (2H, m), 3.84 and 4.36 ( I H, 2 x m), 4. 15 (2H, m), 4.79 and 5.08 (2H, 2 x m), 7.19-7.58 (9H, m).

Found: C, 65.86; H, 6.10; N, 6.47. .H^N requires C, 65.74; H, 5.98; N, 6.39%

Example 44 Preparation of l-benzyl-4-(3,4-dichlorophenyl)carbamyI-7-methyI-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine.

The compound was prepared by an identical route to that used in the preparation of example 10 except that 3,4-dichlorophenylisocyanate was used in step c in place of 3- methylphenylisocyanate.

(CDC1 ₃ ) δ _Η 0.60 (3H, d, J=7Hz), 1.38 and 1.89 (2H, 2 x m), 2.08 and 2.61 (2H, 2 x m), 3.27 and 4.19 (2H, 2 x d, J=15Hz), 4.24 (IH, m), 4.64 and 5.25 (2H, 2 x d, J= 14Hz), 7.10-7.77 (12H, m), 9.80 (IH, s).

Found: C, 63.39; H 5.56; N, 8.38. ^Cl^O,. 0.5H ₂ O requires C, 63.55; H, 5.33; N, 8.55%

Example 45 Preparation of l-benzyl-7-methyl-4-(2-naphthyl)carbamyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine.

The compound was prepared by an identical route to that used in the preparation of example 10 except that 2-naphthylisocyanate was used in step c in place of 3- methylphenylisocyanate.

(CDCI ₃ ) δ _Η 0.60 (3H, d, J=7Hz), 1.47 and 1.93 (2H, 2 x m), 2.14 and 2.65 (2H, 2 x m), 3.31 and 4.24 (2H, 2 x d, J= 15Hz), 4.29 (IH, m), 4.61 and 5.27 (2H, 2 x d, J = 14Hz), 7.14-7.42 (11H, m), 7.64 (IH, m), 7.78 (3H, m), 8.12 (IH, d, J=2Hz), 9.80 (IH, s).

Found: C, 77.41 ; H 6.54; N, 9.18. C ₃₀ H ₂₉ N ₃ O ₂ requires C, 77.75; H, 6.26; N, 9.07%

Example 46 Preparation of l-benzyl-4-(3-(benzyloxycarbonyl)phenylcarbamyl-2,7- dioxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine.

The compound was prepared by an identical route to that used in the preparation of example 3 except that (3-benzyloxycarbonyl)phenylisocyanate was used in step d in place of 3-methylphenylisocyanate.

(CDClj) δ _Η 2.74 and 4.73 (2H, m), 3.00 (2H, m), 3.30 and 4.20 (2H, 2 x d, J= 15Hz), 4.05 and 5.71 (2H, 2 x d, J = 14Hz), 5.35 (2H, dd, J = 12Hz), 6.80 (IH, d), 7.27-7.50 (14H, m), 7.73 (2H, m), 8.13 (IH, m), 9.76 (IH, s).

Found: C, 77.41 ; H 6.54; N, 9.18. requires C, 77.75; H, 6.26; N, 9.07%

Example 47 Preparation of l-benzyl-7-methyl-4-(3,5-dicarboxyphenyl)carbamyl-2- oxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine.

a. 1 -benzyl-7-methyl-4-(3 ,5-dibenzyloxycarbonyl)phenylcarbamyl-2-oxo-2 ,3,4,5,6,7- hexahydro- IH- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 10 except that 3,5-dibenzyloxycarbonylphenylisocyanate was used in step c in place of 3-methylphenylisocyanate.

b. l-benzyl-7-methyl-4-(3,5-dicarboxyphenyl)carbamyl-2-oxo-2, 3,4,5, 6,7-hexahydro- lH-l,4-benzodiazonine.

l-benzyl-7-methyl-4-(3,5-dibenzyloxycarbonyl)phenylcarbam yl-2-oxo-2,3,4,5,6,7- hexahydro-lH-l ,4-benzodiazonine (l lόmg, 0.17mmol) was stirred under a hydrogen atmosphere in the presence of 10% palladium on charcoal (20mg) in methanol- THF(1 : 1/lOml) at room temperature for 24 hours. The reaction mixture was filtered through a pad of celite and evaporated to dryness affording the product. (84mg,

100%)

(d ⁶ -DMSO) δ„ 0.51 (3H, d), 1.44 (IH, m), 1.83-2.01 (2H, ), 2.49(1H, m), 3.2(lH,m), 3.91(1H, bd), 4.32(1H, d), 4.63(1H, d), 5.26(1H, d), 7.16-7.42(9H„m), 8.09(1H, s), 8.22(2H, s), 9.82(1H, bs), 12.5(2H, bs)

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 53.56; H, 6.95; N, 7.04. C^NA _. . 3H ₂ O requires C, 53.33; H 7.09; N, 7.40%.

Example 48 Preparation of l-benzyl-7-methyl-4-(3-carboxyphenyl)carbamyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine.

a. l-benzyl-7-methyl-4-(3-ethyloxycarbonyl)phenylcarbamyl-2-oxo -2, 3,4, 5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 10 except that 3-ethyloxycarbonylphenyIisocyanate was used in step c in place of 3-methylphenylisocyanate.

b. l-benzyl-7-methyI-4-(3-carboxyphenyl)carbamyl-2-oxo-2, 3,4,5, 6,7-hexahydro-lH- 1 ,4-benzodiazonine

A solution of 1 -benzyl-7-methyl-4-(3-ethyloxycarbonyl)phenylcarbamyl -2-oxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine(244mg, 0.5mmol), in IM LiOH (2ml) and THF (2ml) was stirred at room temperature for 20 hours. The reaction mixture was diluted with 2M HCl (4ml), extracted with chloroform (3 x 10ml), and the combined extracts dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purified by flash chromatography on silica gel with ethanol-DCM (1:9) as eluant. (197mg, 86%).

(d ⁶ -DMSO) δ _H 0.57 (3H,d), 1.25-1.42(1H, m), 1.86-1.95(1H, m), 2.10-2.19(1H, m), 2.60-2.66(lH, m), 3.29(1H, d), 4.19-4.31(2H, m), 4.59(1H, d), 5.26( IH, d), 7.12- 7.44(10H, m), 7.77-7.84( 2H, m), 8.22(1H, s), 9.80(1H, s).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 58.86; H, 6.92; N, 8.28. 2.2H ₂ O requires C, 59.04; H 7.04; N, 8.10% .

Example 49 Preparation of l -tert-b utyloxycarbon yl methyl -4- (3 - methylphenyl)carbamyl-2-oxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

a. 2-nitrocinnamyl alcohol.

Sodium borohydride (1.15g, 31.1mmol) was added portionwise to an ice cooled suspension of trans-2-nitrocinnamaldehyde (5.00g, 28.2mmol), and cerium (III) chloride (12.61g, 33.8mmol) in methanol (140ml). After stirring at room temperature for 30 minutes the mixture was poured into saturated aqueous NH _t Cl (200ml), extracted with DCM (3 x 150ml) and the extacts dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product. (5.03g, 100%)

b. 2-(3-tert-butyldimethylsilyloxyprop-2-enyl)nitrobenzene

Tert-butyldimethylchlorosilane (5.10g, 33.8mmol) was added to a solution of 2- nitrocinnamyl alcohol (5.05g, 28.2mmol) and imidazole (2.88g, 42.3mmol) in DMF (100ml). After stirring at room temperature for 18 hours the reaction mixture was partitioned between water (200ml) and ethyl acetate (200ml). The organic layer was separated washed with brine (2 x 100ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purified by flash chromatography on silica gel with ethyl acetate-hexane (1 :3) as eluant. (7.82g, 95 %).

c. 2-(3-tert-butyldimethylsilyloxypropyl)aniline

A suspension of 2-(3-tert-butyldimethylsilyloxyprop-2-enyl)nitrobenzene (7.82g, 26.7mmol), and 10% palladium on charcoal (0.8g) in methanol (100ml) was stirred under a hydrogen atmosphere for 5 hours. The reaction mixture was filtered through a pad of celite and the filtrate evaporated to give the crude product, which was purified by flash chromatography on silica gel with ethyl acetate-hexane (1:8) as eluant. (6.65g, 94%)

d. N-(Benzyloxycarbonylaminomethylcarbonyl)-2-(3-tert-butyldime thyl- silyloxypropyl)aniline

A solution of 2-(3-tert-butyldimethylsilyloxypropyl)aniline (4.42g, 15.9mmol) EDC (3.36g, 17.5mmol), HOBt (2.37g, 17.5mmol) and Z-glycine (4.99g, 23.9mmol) in DMF (50ml) was stirred at room temperature for 20 hours. The reaction mixture was diluted with water (150ml), and extracted with ethyl acetate (200ml). The extract was washed with saturated aqueous sodium bicarbonate solution (200ml), brine (2 x 150ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purified by flash chromatography on silica gel with ethyl acetate-hexane (2:3) as eluant. (6.76g, 93%).

e. N-(Benzyloxycarbonylaminomethylcarbonyl)-N-(tert-butyloxycar bonylmethyl)- 2-(3-tert-butyldimethylsilyloxypropyl)aniline

Sodium hydride (60% dispersion in oil/652mg, 16.3mmol) was added to a solution of N-(benzyloxycarbonylaminomethylcarbonyl)-2-(3-tert-butyldime thylsilyloxy- propyl)aniline (6.76g, 14.8mmol) in DMF (30ml). After stirring at room temperature for 1 hour, tert-butylbromo acetate (2.19ml, 14.8mmol) was added and stirring continued at room temperature for 1 hour. The reaction mixture was diluted with water (150ml) and extracted with ethyl acetate (2 x 150ml). The organic extract was washed with brine (2 x 150ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purified by flash chromatography with ethyl

acetate-hexane (1 :3) as eluant. (3.87g, 46%)

f. N-(Benzyloxycarbonylaminomethylcarbonyl)-N-(tert-butyloxycar bonylmethyl)-

2-(3-hydroxypropyl)aniline

Tetrabutylammonium fluoride (1.0M in THF/ 10ml, lOmmol) was added to a solution of N-(benzyloxycarbonylaminomethylcarbonyl)-N-(tert-butyloxycar bonyl- methyl)-2-(3-tert-butyldimethylsilyloxypropyl)aniline(3.87g, 6.8mmol)in THF (25ml) at room temperature. After stirring for 90 minutes the reaction mixture was diluted with ethyl acetate (150ml), washed with water (150ml), brine (150ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purified by flash chromatography on silica gel with ethyl acetate-hexane (2: 1) as eluant (2.39g, 77%).

g. N-(Ifenzyloxycarbonylarninomethylcarbonyl)-N-(tert-butyloxyc arbonylmethyl)- 2-(3-(4-methyl)phenylsulphonyloxypropyl)aniline

para-Toluenesulphonyl chloride (1.33g, 6.98mmol) was added in a single portion to a solution of N-(benzyloxycarbonylaminomethylcarbonyl)-N-(tert- butyloxycarbonylmethyl)-2-(3-hydroxypropyl)aniline (2.12g, 4.66mmol), DMAP (132mg, 1.08mmol) and triethylamine (1.51ml, 10.85mmol) in DCM (10ml). After stirring at room temperature for 1 hour the mixture was diluted with DCM (100ml), washed with water (100ml), 10% citric acid solution (100ml), saturated aqueous sodium bicarbonate solution (100ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purified by flash chromatography on silica gel with ethyl acetate-hexane (2:3) as eluant. (2.12g, 75%).

h. l-tert-Butyloxycarbonylmethyl-4-benzyloxycarbonyl-2-oxo-2, 3,4,5, 6,7-hexahydro- 1H- 1 ,4-benzodiazonine

Sodium hydride (60% dispersion in mineral oil/ 167mg,4.12mmol) was added in a single portion to a solution of N-(benzyloxycarbonylaminomethylcarbonyl)-N-(tert-

butyloxycarbonylmethyl)-2-(3-(4-methyl)phenylsulphonyloxypro pyl)aniline (2.12g, 3.48mmol) in DMF (40ml) at room temperature. After stirring for 16 hours the mixture was partitioned between water (100ml) and ethyl acetate (100ml). The organic layer was separated washed with brine (3 x 100ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product. (1.52g, 100%).

i. l-tert-Butyloxycarbonylmethyl-2-oxo-2,3,4,5,6,7-hexahydro- l H- l ,4- benzodiazonine

A suspension of l-tert-butyloxycarbonylmethyl-4-benzyloxycarbonyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine(1.52g, 3.48mmol),and 10% palladium on charcoal (0.2g) in methanol (20ml) was stirred under a hydrogen atmosphere for 4 hours. The reaction mixture was filtered through a pad of celite and the filtrate evaporated to give the crude product, which was purified by flash chromatography on silica gel with methanol-DCM(l: 12) as eluant. (996mg, 95%)

j . 1 -tert-Butyloxycarbonylmethyl-(3-methylphenyl)carbamyl-2-oxo- 2 ,3,4,5,6,7- hexahydro-lH-1 ,4-benzodiazonine

A solution of l-tert-butyloxycarbonylmethyl-2-oxo-2,3,4,5,6,7-hexahydro-lH -l,4- benzodiazonine (438mg, 1.44mmol) and m-tolylisocyanate (0.2ml, l.όmmol) in DCM (4ml) was stirred at room temperature for 90 minutes. Evaporation of the solvent gave the crude product which was purified by flash chromatography on silica gel with ethyl acetate-hexane (1:2) as eluant. (550mg, 87%)

(CDCl ₃ ) δ„ 1.51(9H,s), 1.76and 2.10(lH,m), 2.26 and 4.30(lH,m), 2.33(3H,s), 2.66- 2.87(2H,m), 3.39 and 4.15(1H,2 x d), 3.79 and 4.65(1H,2 x d), 6.82(lH,m), 7.14- 7.50(7H,m), 9.17(lH,bs)

Found: C, 68.71 ; H, 7.18; N, 9.42. requires C, 68.63; H 7.14; N, 9.60%

Example 50 Preparation of l-benzyl-7-phenyl-4-(3-methylphenyl)carbamyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine

a. N-Butyloxycarbonyl-2-benzylaniline

A solution of 2-benzyIaniline (6.04g, 33mmol), and di-tert-butyldicarbonate (7.92g, 36mmol), in THF (30ml) was heated at reflux for 2 hours. The reaction mixture was concentrated in vacuo and the residue partitioned between ethyl acetate (100ml) and 10% citric acid solution (100ml). The organic layer was separated and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product which was recrystallised from hexane (7.36g, 79%).

b. N-Butyloxycarbonyl-2-(l-phenylprop-3-enyl)aniline

n-Butyl lithium (1.6M in hexane/ 14ml, 22mmol) was added dropwise over 10 minutes to a solution of N-butyloxycarbonyl-2-benzylaniline (2.83g, lOmmol) in THF (40ml) at -40°C. After stirring for 5 minutes allyl bromide (0.87ml, lOmmol) was added and the reaction mixture allowed to warm to room temperature, and stirring continued for 1 hour. The reaction mixture was partitioned between ethyl acetate (100ml) and saturated aqueous NH ₄ C1 solution (100ml). The organic layer was separated, washed with brine (100ml) and dried (MgSO ₄ ), filtered and evaporated to leave the product. (3.42g, 100%)

c. N-butyloxycarbonyl-2-(3-hydroxy- 1 -phenylpropyμaniline

Ozone was bubbled through a solution of N-butyloxycarbonyl-2-(l-phenylprop-3- enyl)aniline (3.42g, lOmmol) in methanol (30ml) for 30 minutes at -78°C. The solution was then purged with nitrogen followed by the addition of sodium borohydride (925mg, 25mmol). After stirring for 10 minutes at -78°C, the reaction mixture was allowed to warm to room temperature and stirring continued for 16 hours. The reaction mixture was diluted with saturated aqueous NH ₄ C1 solution (150ml), and extracted with ethyl acetate (2 x 100ml). The extracts were washed with

brine (100ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product which was purified by flash chromatography on silica gel with ethyl acetate- hexane (1 :2 to 1 : 1) as eluant. (1.21g 37%)

d. N-butyloxycarbonyl-2-(3-acetoxy-l-phenylpropyl)aniIine

Acetic anhydride (0.42ml, 4.4mmol) was added to a solution of N-butyloxycarbonyl-2- (3-hydroxy-l-phenylpropyl)aniline (1.21g, 3.7mmol), triethylamine (0.77ml, 5.56mmol) and DMAP (5mg) in DCM (25ml). After stirring at room temperature for 90 minutes the reaction mixture was diluted with DCM (25ml), washed with 10% aqueous citric acid solution (40ml), saturated aqueous sodium bicarbonate solution (40ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product. (1.39g, 100%).

e. 2-(3-acetoxy-l-phenylpropyl)aniline

A solution of N-butyloxycarbonyl-2-(3-acetoxy-l-phenylpropyl)aniline (1.39g, 3.7mmol) in CHC1 ₃ -TFA (l: l/10ml) was stirred at room temperature for 20 minutes. The reaction mixture was neutralised with saturated aqueous sodium bicarbonate solution (30ml), extracted with DCM (3 x 30ml) and the extracts dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the product. (939mg, 94%)

f. l-benzyl-7-phenyl-4-(3-methylphenyl)carbamyl-2-oxo-2, 3,4,5, 6,7-hexahydro-lH- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 49 except that 2-(3-acetoxy-l-phenylpropyl)aniline was used in place of 2- (3-tert-butyldimethylsilyloxypropyl)aniline in step d.

(CDC1 ₃ ) δ _H 1.99-2.08(2H,m), 2.35(3H,s), 2.73-2.76(2H,m), 3.36(lH,d), 4.20-

4.49(4H,m), 5.51 (2H,d), 6.86-7.39(18H,m), 9.38(lH,s).

Found: C, 78.56; H, 6.47; N, 8.60. C ₃₃ H ₃₃ N ₃ O ₂ . requires C, 78.70; H 6.60; N, 8.34%

Example 51. Preparation of l-benzyl-7-ethyl-4-(3-methylphenyl)carbamyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine

The compound was prepared by a similar method to that used in the preparation of example 50 except that 2-propyl aniline was used in place of 2-benzyl aniline in step a.

(CDCl ₃ ) δ _H 0.71(3H,t), 1.15-1.57(3H,m), 1.90(lH,m), 2.18-2.35(4H,m),2.60(lH,m), 3.27(lH,d), 4.21(lH,d), 4.26(lH,m), 4.48(lH,d), 5.25(lH,d), 6.85-6.88(2H,m), 7.17-7.39(1 lH,m), 9.44(lH,s).

Found: C, 75.88; H, 7.09; N, 9.48. gHjjNjOj. requires C, 76.16; H 7.08; N, 9.52%

Example 52. Preparation of l-benzyl-7-ethyl-4-(3,4-dichlorophenyl)carbamyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine

The compound was prepared by a similar method to that used in the preparation of example 49 except that 3,4-dichlorophenylisocyanate and l-benzyl-7-ethyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazoninewere used in place of m-tolylisocyanate and l-tert-butyloxycarbonylmethyl-2-oxo-2,3,4,5,6,7-hexahydro-lH - l ,4- benzodiazonine respectively in step j.

(CDCI ₃ ) δ _H 0.72(3H,t), 1.17-1.22(lH,m), 1.51(lH„m), 1.54-1.58(lH,m), 1.93-

1.99(lH,m), 2.25-2.30(lH,m), 2.58-2.61(lH,m), 3.27(lH,d), 4.14(lH,d), 4.23- 4.29(lH,m), 4.44(1H, d), 5.27(lH,d), 6.86-6.89(lH,m), 7.21-7.43(10H,m),

7.76(l H,m), 9.72(l H,s).

Found: C, 64.97; H, 5.52; N, 8.27. .H^CI . requires C, 65.32; H 5.48; N, 8.46%

Example 53. Preparation of l-benzyl-7-ethyl-4-(2-indolecarbonyl)-2-oxo-2,3,4,5,6,7- hexahydro-lH-l,4-benzodiazonine

A mixture of l-benzyl-7-ethyl-2-oxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine (446mg, 1.45mmol), EDC (306mg, 1.6mmol), HOBt (215mg, 1.6mmol) and 2- indolecarboxylic acid (350mg, 2.2mmol) in DMF (5ml) was stirred at room temperature for 18 hours. The reaction mixture was partitioned between water (50ml) and ethyl acetate (50ml). The organic layer was separated, washed with saturated aqueous NaHCO ₃ solution (50ml), brine (2 x 50ml) and dried (MgSO ₄ ). Filtration and evaporation of the solvent gave the crude product which was purifeid by flash chromatography on silica gel with ethyl acetate-hexane (1:2) as eluant. (479mg, 73%)

(CDC1 ₃ ) δ _H 0.77(3H,t), 1.19-1.29(lH,m), 1.56-1.65(2H,m), 2.18-2.24(2H,m), 2.63(lH,m), 3.50-3.52(lH,m), 4.47-4.65(3H,m), 5.31(lH,d), 6.86-7.68(14H,m), 12.0(lH,s)

Found: C, 76.86; H, 6.51; N, 9.27. C^H^O^ requires C, 77.13; H 6.47; N, 9.31 %

Example 54 Preparation of l-benzyl-4-(3-methylphenyl)carbamyl-2-oxo-2, 3,4,5, 6,7- hexahydro-lH- 1 ,4-benzodiazonine.

The compound was prepared by an identical route to that used in the preparation of example 49 except that Boc-glycine was used in place of Z-glycine in step d, and benzyl bromide was used in place of tert-butyl bromoacetate in step e.

(CDC1,) δ _H 1.60 (IH, ), 1.97-2.31(4H, m), 2.36( 3H, s), 3.32(1H, d), 4.16(1H, d), 4.21-4.29(lH,m), 4.74(1H, d), 4.98(1H, d), 6.82( IH, d), 7.02-7.38(12H,m),

9.51(1H, s).

Found: C, 75.24; H, 6.59; N, 10.23. requires C, 75.52; H 6.58; N, 10.16%.

Example 55 Preparation of l -tert-butyloxycarbonylmethyl-4-(3- methoxyphenyl)carbamy l-2-oxo-2 ,3,4,5,6, 7-hexahydro- 1 H- 1 , 4-benzodiazonine

The compound was prepared by a similar route to that used in the preparation of example 49 except that 3-methoxyphenylisocyanate was used in step j in place of 3- methylphenylisocyanate.

(CDClj) δ„ 1.51(9H,s), 1.75 and 2.10(2H, 2 x m), 2.30 and 4.32(2H,2 x m), 2.71- 2.86(2H,m), 3.39 and 4.15(2H,2 x d), 3.78 and 4.64(2H,2 x d), 3.81(3H,s), 6.54- 6.59(1H, m), 7.00-7.08(lH,m), 7.14-7.50(6H,m), 9.28(lH,s).

Found: C, 66.19; H, 6.92; N, 9.28. sHs.NjOs. requires C, 66.21; H 6.89; N, 9.27%

Example 56 Preparation of l-carboxymethyl-4-(3-methylphenyl)carbamyl-2-oxo- 2,3,4,5,6, 7-hexahydro- 1 H- 1 , 4-benzodiazonine

A solution of l-tert-butyloxycarbonylmethyl-4-(3-methylphenyl)carbamyl-2-o xo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine(408mg, O.93mmol) in CHC1 ₃ -TFA (5: 1/ 12ml) was stirred at room temperature for 16 hours. Evaporation of the solvent gave the product. (360mg, 100%)

(d ⁶ -DMSO) δ _H 1.75-2.0(2H,m), 2.26(3H,s), 2.64-2.79(lH,m), 3.49(1H, d), 3.88(1H, d), 4.04-4.1 1(2H, ), 4.74(lH,d), 6.76(lH,m), 7.10-7.48(7H,m), 9.01(lH,s), 12.5( l H,bs).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Example 57 Preparation of l-carboxymethyl-4-(3-methoxyphenyl)carbamyl-2-oxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example56exceptthatl-tert-butyloxycarbonylmethyl-4-(3-methox yphenyl)carbamyl-2- oxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine was used in place of 1-tert- butyloxycarbonyImethyl-4-(3-methylphenyl)carbamyl-2-oxo-2,3 ₎ 4,5,6,7-hexahydro-lH- 1 ,4-benzodiazonine.

(d ⁶ -DMSO) δ _H 1.82-1.96(2H,m), 2.15 and 4.48(1H,2 x m), 2.64-2.79(2H,m), 3.51(lH,d),3.71(3H,s), 3.85(lH,d),4.04-4.10(2H,m),4.48(lH,d), 6.51-6.55(lH,m), 6.83-6.85 (lH,m), 7.06-7.17(2H,m)

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 52.01 ; H, 7.02; N, 8.58. C^H^NA. . 3H ₂ Orequires C, 52.00; H 7.17; N, 8.66%

Example58 Preparation of (3R.5S)-4-acetyl-3-( 1 -adamantyllmethyl- 1 -(4-fluorohenzyl)- 5-carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro - lH-l ,4- benzodiazonine.

The compound was prepared by an identical route to that used to prepare example 22 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(4-fluorobenzyl)-2, 7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro-lH-1 ,4-benzodiazonine-5-carboxylate.

(CDCl,) δ _H 1.08(lH,d), 1.23(3H,s), 1.20-1.73(12H,m), 1.88(3H,s), 2.35(lH,m),

2.63(lH,t), 3.31(lH,t),4.05(4H,m), 4.26(lH,d),5.26(lH,s), 5.73(lH,d), 6.72(lH,d), 6.95(2H,m), 7.2(5H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 59.98; H, 7.21; N, 6.50. C ₄₁ H ₅₅ FNAι- 1.4H ₂ O requires C, 59.77; H 7.07; N, 6.80%

Example59Preparationof(3R.5S>-4-acetyl-3-(l-adamantyI) methyl-l-f2-fluorohenzyl)- 5-carboxy methy laminocarbony 1-2, 7-dioxo-2, 3, 4,5,6, 7-hexahydro-lH- 1 ,4- benzodiazonine.

The compound was prepared by an identical route to that used to prepare example 22 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2-fluorobenzyl)-2, 7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5 -carboxylate

(CDC1 ₃ ) δ _H 1.15(lH,m), 1.22(3H,s), 1.20-1.73(12H,m), 1.88(3H,s), 2.35(lH,dt), 2.64(lH,t), 3.07(lH,q), 4.03 and 4.35(4H,m), 4.10(lH,d), 5.40(lH,d), 6.37(lH,t), 7.04(3H,m), 7.24-7.47(5H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 59.99; H, 7.03; N, 6.79. C ₄₁ H ₅₅ FN ₄ O _u . 1.2H ₂ O requires C, 60.02; H 7.05; N, 6.83%

Example 60. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(3- fluorobenzyl)-5-carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5 ,6,7-hexahydro-lH- 1 ,4-benzodiazonine.

The compound was prepared by an identical route to that used to prepare example 22

except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(3-fluorobenzyl)-2, 7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyI-2,7-dioxo-2, 3,4,5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5-carboxylate.

(CDC1 ₃ ) δ _H 1.10(lH,d), 1.24(3H,s), 1.20-1.90(12H,m), 1.90(3H,s), 2.37(lH,m), 2.64(lH,m), 3.63(lH,q), 4.02(4H,m), 5.77(lH,d), 6.76(lH,d), 7.03(3H,m), 7.20- 7.35(5H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 59.86; H, 7.18; N, 6.76. C _4] H ₅₅ FN ₄ O _u . 1.3H ₂ O requires C, 59.89; H 7.06; N, 6.81 %

Example 61. Preparation of (+/-)-trans-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5- carboxymethylaminocarbonyl-2,7-dioxo-9-fluoro-2,3,4,5,6,7-he xahydro-lH-l ,4- benzodiazonine.

a. (+/-)-trans-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-diox o-2,3,4,5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5-carboxylate

The compound was prepared by an identical route to that used to prepare example 11 except that (R/S)-5-fluoro-tryptophan benzyl ester was used in step a in place of L- tryptophan benzyl ester.

b. ( + /-)-trans-4-acetyl-3-( 1 -adamantyl)methyl- l-benzyl-5-carrx)xymemylarmnocarbonyl- 2,7-dioxo-9-fluoro-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

The compound was prepared by an identical route to that used to prepare example 22 except that (+/-)-trans-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-diox o-

2,3,4,5,6,7-hexahydro- IH-l ,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7-

hexahydro-lH-l ,4-benzodiazonine-5-carboxylate

(CDCI ₃ ) δ _H 1.20(lH,d), 1.32(3H,s), 1.38(6H,d), 1.58(6H,q), 2.10(3H,s), 2.72(lH,dd), 3.05(lH,dd), 3.86(lH,d), 4.04(4H,m), 4.08(lH,d), 5.60(lH,d), 6.42(lH,t), 6.70(lH,q), 7.03 and 7.20(lH,m), 7.27(2H,m), 7.30(3H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 57.71; H, 6.96; N, 6.90. .H _J JFN _. . l-35H ₂ O requires C, 59.81 ; H 7.06; N, 6.81 %

Example 62. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(3- chlorobenzy l)-5 -carboxy methylaminocarbonyl-2 , 7-dioxo-2 , 3 ,4 , 5 , 6 ,7-hexahydro- 1 H- 1 ,4-benzodiazonine.

The compound was prepared by an identical route to that used to prepare example 22 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(3-chlorobenzyl)-2, 7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5-carboxylate

(CDCI ₃ ) δ _H 1.20(3H,d), 1.36(2H,s), 1.53-1.82(10H,m), 1.95(3H,s), 2.72(lH,t), 3.10(lH,d), 3.88(lH,d), 4.00-4.13(4H,m), 5.63(lH,d), 6.53(lH,bs), 6.84(lH,d), 7.10(lH,d), 7.10-7.51(6H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 59.08; H, 6.92; N, 6.27. C _4I H ₅₅ ClN ₄ O _n .H ₂ O requires C, 59.10; H 6.89;

N, 6.72%

Example 63. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2- chlorobenzyl)-5-carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5 ,6,7-hexahydro-lH-

1 ,4-benzodiazonine.

The compound was prepared by an identical route to that used to prepare example 22 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2-chlorobenzyl)-2, 7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2, 7-dioxo-2, 3,4,5, 6,7- hexahydro- IH- 1 ,4-benzodiazonine-5-carboxylate

(CDCl ₃ ) δ _H 1.25(6H,m), 1.40-1.74(12H,m), 1.95(3H,s), 2.69(lH,t), 3.10(lH,q), 4.10- 4.25(5H,m), 5.64(lH,d), 6.46(lH,bs), 6.86(lH,d), 7.10(lH,t), 7.10-7.42(6H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.09; H, 6.74; N, 6.74. Q.^CINA, requires C, 60.40; H 6.80; N, 6.87%

Example 64. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2- fluorobenzyl)-5-[( 1 S)-carboxy]ethylaminocarbonyl-2 , 7-dioxo-2 , 3 ,4 ,5 , 6,7-hexahydro- 1H- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used to prepare example 24 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2-fluorobenzyI)-2, 7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5-carboxylate

(CDC1 ₃ ) δ _H 1.10(lH,d), 1.21(3H,s), 1.28-1.70(13H,s), 1.89(3H,s), 2.70(lH,t), 3.05(lH,d), 4.00-4.20(3H,m), 4.25(lH,d), 4.52(lH,t), 5.45(lH,d), 6.43(lH,d), 7.07(3H,m), 7.27-7.45(6H,m).

Found: C, 60.71 ; H, 7.70; N, 6.66. C ₄₂ H ₅₇ FNA, .H ₂ O requires C, 60.68; H 7.15; N, 6.74%

Example 65. Preparation of (3R,5S)-4-acetyI-3-(l-adamantyl)methyI-l-(2- fluorobenzyl)-5-methanesulphonamidocarboxymethylaminocarbony l-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

The compound was prepared by an identical route to that used to prepare example 41 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2-fluorobenzyl)-5- carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-l H-l,4-benzodiazonine was used in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5- carboxymethylaminocarbonyl-2 , 7-dioxo-2, 3 ,4,5 , 6,7-hexahydro- 1 H- 1 ,4-benzodiazonine

(CDC1 ₃ ) δ _H 1.20(lH,d), 1.24(3H,s), 1.21-1.67(12H,m), 1.83(3H,s), 2.60(lH,dd), 3.11(lH,dd), 3.22(3H,s), 3.90(2H,m), 4.10(3H,m), 4.20(lH,d), 5.35(lH,d), 6.45(lH,s), 7.04(3H,m), 7.33(3H,m), 7.44(3H,m).

The compound was further characterised and tested as the sodium salt.

Found: C, 58.20; H, 5.76; N, 7.82. .H ₂ O requires C, 58.30; H

5.87; N, 7.77%

Example 66. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2- fluorobenzyl)-5-[(lS)-methanesulphonamidocarboxy]ethylaminoc arbonyl-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine

The compound was prepared by an identical route to that used to prepare example 41 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2-fluorobenzyl)-5- [(lS)- cartκ)xy]e ylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzo diazonine was used in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5- carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-l H-l ,4-benzodiazonine

(CDCl ₁ ) δ _H l .00(l H,d), l .20-1.26(3H,d), l .32-1.72(l2H,m), l .90(3H,s), 2.63(lH,t), 3.00(l H,2 x dd), 3.25(3H,s), 3.80-4.24(5H,m), 5.40(2H,m), 5.80(lH,bs), 6.25(lH,bs), 7.03(3H,m), 7.27-7.37(4H,m), 7.44-7.48(2H,m), 9.38 and 9.69(lH,2

x s).

The compound was further characterised and tested as the sodium salt.

Found: C, 59.99; H, 5.93; N, 7.86. ^FNASNa requires C, 60.32; H 5.91 ; N,

7.82%

Example 67. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5- tetrazolomethylaminocarbonyl-2 ,7-dioxo-2 ,3 ,4,5,6, 7-hexahydro- 1 H- 1 ,4-benzodiazonine

a. (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-N-pivaloyl oxymethyl-(5- tetrazolo)methylaminocarbonyl-2,7-dioxo-2,3 ,4,5,6,7-hexahydro- l H- l ,4- benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 24 except that 5-(N-pivaloyloxymethyl)tetrazolmethylamine was used in place of L-alanine benzyl ester.

b. (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-(5-tetrazo lo)methylamino- carbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazoni ne

A solution of methylamine in IMS (33% w/w; 0.1ml) was added to a solution of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5-N-pivaloyl oxymethyl-(5-tetra--θlo)- methylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine (210mg, 0.3mmol) in methanol-DCM (1:8/2.25 ml) at room temperature. After stirring for 17 hours the reaction mixture was diluted with DCM (20ml), washed with 5% aqueous KHSO ₄ solution (20ml), brine (20ml), and dried (Na ₂ SO ₄ ). Filtration and evaporation of the solvent gave the crude product, which was purified by flash chromatography on silica gel with methanol-DCM (1: 10) as eluant (123mg, 70%)

(d ⁶ -DMSO) δ _H 1.04(3H,s), 1.26-1.66(12H, m), 1.87(3H,m), 2.40(lH,t), 3.00(l H,dd), 3.90(lH,m), 3.95(3H,m), 4.40(2H,d), 5.35(lH,d), 7.05(lH,m), 7.21-7.31(6H,m),

7.50-7.53(3H,m), 7.60(lH,t).

The compound was further characterised and tested as the sodium salt.

Found: C, 61.01; H, 6.12; N, 14.68. C^N Na .2H ₂ O requires C, 61.16; H 6.34; N, 14.68%

Example 68. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2- fluorobenzyl)-5-(5-tetrazolo)methylaminocarbonyl-2,7-dioxo-2 , 3,4,5, 6,7-hexahydro- 1 H- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used in the preparation of example 67 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2-fluorobenzyl)-5- (5-tetrazolo)methylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hexah ydro- lH- l ,4- benzodiazonine was used in place of (3R ,5S)-4-acetyl-3-( 1 -adamantyl)methyl- 1 -benzyl- 5-(5-tetrazolo)methylaminocarbonyl-2,7-dioxo-2,3,4,5,6,7-hex ahydro-lH-l ,4- benzodiazonine

(d ⁶ -DMSO) δ _H 1.06(3H,s), 1.22-1.63(12H,m), 1.83(3H,s), 2.35(lH,m), 2.95(lH,dd), 3.75(lH,m), 3.96(2H,m), 4.08(lH,d), 4.35(2H,m), 5.28(lH,d), 7.10(3H,m), 7.33(3H,m), 7.50(3H,m).

The compound was further characterised and tested as the sodium salt.

Found: C, 61.01 ; H, 6.12; N, 14.68. C ₃₄ H ₃₈ N ₇ O ₄ Na .2H ₂ O requires C, 61.16; H 6.34; N, 14.68%

Example 69. Preparation of (+/-)-trans-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5- carboxymethylaminocarbonyl-2,7-dioxo-9-methoxy-2,3,4,5,6,7-h exahydro- lH-l ,4- benzodiazonine

The compound was prepared by an identical route to that used to prepare example 61

except that (R/S)-5-methoxy-tryptophan benzyl ester was used in step a in place of (R/S)-5-fluoro-tryptophan benzyl ester

(CDCI ₃ ) δ„ 1.18(lH,d), 1.34(3H,s), 1.38(3H,m), 1.54-1.73(9H,m), 1.94(3H,s), 2.72(lH,t), 3.04(lH,dd), 3.85(3H,s), 3.92(lH,d), 4.00(3H,m), 4.15(lH,d), 5.60(lH,d), 6.45(lH,bs), 6.65(lH,d), 6.88(2H,m), 7.20-7.30(6H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 59.53; H, 7.28; N, 6.63. C ₄₂ H ₅₈ N ₄ O, ₂ -2H ₂ O requires C, 59.62; H 7.37; N, 6.62%

Example 70. Preparation of (+/-)-trans-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-5- carboxymethylaminocarbonyl-2,7-dioxo-9-methyl-2,3,4,5,6,7-he xahydro-lH-l ,4- benzodiazonine

The compound was prepared by an identical route to that used to prepare example 61 except that (R/S)-5-methyl-tryptophan benzyl ester was used in step a in place of (R/S)-5-fluoro-tryptophan benzyl ester

(CDCI ₃ ) δ _H 1.24(3H,s), 1.38(3H,m), 1.53-1.78(12H,m), 1.93(3H,s), 2.37(3H,s), 2.70(lH,t), 3.04(lH,m), 3.89-4. l l(5H,m), 5.60(lH,d), 6.50(lH,bs), 6.65(lH,d), 7.18-7.27(7H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 59.08; H, 6.92; N, 6.27. C ₄₁ H _j5 ClN ₄ O _n .H ₂ O requires C, 59.10; H 6.89;

N, 6.72%

Example 71. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(3- methylbenzyl)-5-carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5 ,6,7-hexahydro- l H- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used to prepare example 22 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(3-methylbenzy_)-2, 7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5-carboxylate

(CDC1 ₃ ) δ _H l. l l(3H,s), 1.29(3H,m), 1.49-1.67(9H,s), 1.88(3H,s), 2.23(3H,s), 2.63(lH,t), 2.97(lH,q), 3.78-4.04(5H,m), 5.54(lH,d), 6.50(lH,bs), 6.72(lH,d), 6.91(lH,d), 7.00-7.12(3H,m), 7.27-7.42(4H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 58.67; H, 7.39; N, 6.46. AgNA, .3.4H ₂ O requires C, 58.91; H 7.63; N, 6.54%

Example 72. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(4- methylbenzyl)-5-carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5 ,6,7-hexahydro-lH- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used to prepare example 22 except that (3R,5S)-4-acetyl-3-( 1 -adamantyl)methyl- 1 -(4-methylbenzyl)-2,7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5 -carboxylate

(CDCI ₃ ) δ _H 1.20(6H,m), 1.35-1.74(9H,m), 1.95(3H,s), 2.34(3H,s), 2.71(lH,t), 3.08(lH,dd), 3.92(lH,d), 4.02-4.09(4H,m), 5.59(lH,d), 6.47(lH,bs), 6.78(lH,d), 7.07(3H,m), 7.16-7.27(2H,m), 7.36-7.46(4H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.07; H, 7.59; N, 6.66. C ₄₂ H ₅₈ N ₄ O„ .2.5H ₂ O requires C, 60.06; H 7.56;

N, 6.67%

Example 73. Preparation of (3S,5R)-4-acetyl-3-(l-adamantyl)methyl-l-(2- fl uorobenzy l)-5-carboxymethylaminocarbonyl-2 , 7-dioxo-2 , 3 , 4 ,5 , 6, 7-hexahydro- 1 H- 1,4-benzodiazonine

The compound was prepared by an identical route to that used to prepare example 22 except that (3S,5R)-4-acetyl-3-(l-adamantyl)methyl-l-(2-fluorobenzyI)-2, 7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5-carboxylate

(CDC1 ₃ ) δ _H 1.21(4H,s), 1.20-1.74(12H,m), 1.95(3H,s), 2.34(3H,s), 2.69(lH,dd), 3.06(lH,dd), 3.90(lH,d), 4.02(5H,d), 5.57(lH,d), 6.77(lH,d), 7.10(5H,m), 7.40(2H,m).

Example 74. Preparation of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2- methylbenzyl)-5-carboxymethylaminocarbonyl-2,7-dioxo-2,3,4,5 ,6,7-hexahydro-lH- 1 ,4-benzodiazonine

The compound was prepared by an identical route to that used to prepare example 22 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(2-methylbenzyl)-2, 7-dioxo- 2,3,4,5,6,7-hexahydro-lH-l ,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- 1 H- 1 ,4-benzodiazonine-5-carboxylate

(CDCl ₃ ) δ _H 1.20(3H,s), 1.15-1.30(4H,m), 1.43-1.69(10H,m), 1.87(3H,s), 2.60(lH,t), 2.64(lH,t), 3.10(lH,ra), 3.97(2H,m), 4.05(3H,m), 4.20(lH,d), 5.41(1H, d), 6.47(lH,bs), 7.06(3H,m), 7.24-7.46(6H,m).

Example 75. Preparation of (3R,5S)-4-acetyI-3-(l -adamantyl)methyI- l -(4- methoxybenzyl)-5-carboxymethylaminocarbonyl-2,7-dioxo-2,3,4, 5,6,7-hexahydro- lH-

1 ,4-benzodiazonine

The compound was prepared by an identical route to that used to prepare example 22 except that (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-(4-methoxybenzyl)-2 ,7-dioxo- 2,3,4,5, 6, 7-hexahydro-lH-l,4-benzodiazonine-5-carboxylate was used in step a in place of (3R,5S)-4-acetyl-3-(l-adamantyl)methyl-l-benzyl-2,7-dioxo-2, 3,4,5,6,7- hexahydro- IH- 1 ,4-benzodiazonine-5-carboxylate

(CDCl ₃ ) δ _H 1.17(3H,s), 1.20-1.37(6H,m), 1.53-1.68(9H,m), 1.94(3H,s), 2.70(lH,t), 3.00(lH,q), 3.35-3.41(3H,m),3.80(3H,s), 3.93-4.04(3H,m),5.53(lH,d),6.55(lH,t), 6.73-6.81(3H,m), 7.03-7.13(2H,m), 7.40-7.48(2H,m).

The compound was further characterised and tested as the N-methyl-D-glucamine salt.

Found: C, 60.46; H, 7.64; N, 6.92. C ₄₂ H ₅₈ N ₄ O _u .2H ₂ O requires C, 60.64; H 7.52; N, 6.73%

The compounds of the examples were tested for binding at the CCK _B receptor in mouse cortical membranes by means of a radioligand binding assay. The procedure was as follows:

The whole brains from male mice (CD1 22-25g; Charles River) were removed and placed in ice-cold buffer (pH7.2 @ 21 + 3°C) of the following composition (mM); 10 HEPES, 130 NaCl, 4.7 KCl, 5 MgCl ₂ , 1 EDTA and containing 0.25g.l"' bacitracin. The cortex was dissected, weighed and homogenised in 40ml ice-cold buffer using a Teflon-in-glass homogeniser. The homogenate was centrifuged at 39,800g for 20 min at 4°C, the supernatant discarded and the pellet resuspended by homogenisation in fresh buffer. The homogenate was recentrifuged (39,800g; 20 min @ 4°C) and the final pellet was resuspended in HEPES buffer to give a tissue concentration of 2mg.m ' (original wet weight).

The membranes (400μl) were incubated for 150 min at 21 + 3°C in a final volume of 0.5ml with HEPES buffer containing [ ^,25 I]-CCK8S (0.05ml; 200pM NEN 2200Ci.mmol ^"1 ) and competing compound. Total and non-specific binding of [ ^I25 I]-CCK8S were defined using 0.05ml of buffer and 0.05ml of lOmM L-365,260, respectively. The assay was terminated by rapid filtration through pre-soaked Whatman GF/B filters using a Brandell Cell harvester. The filters were washed (3 x 3ml) with ice-cold 50mM Tris-HCl (pH7.4 @ 4°C) and bound radioactivity determined by counting (1 min.) in a gamma-counter.

The compounds of the examples were also tested in a CCK _A binding assay as follows:

The pancreatata were removed from male guinea-pigs (200-300g; Dunkin Hartley) and placed in ice-cold HEPES buffer (pH 7.2 @ 21 ± 3'C). The pancreatata were homogenised in 40 ml ice-cold HEPES buffer using a polytron (Brinkmann, PT10, setting 10) 4 x 1 second. The homogenate was centrifuged at 39,800g for 15 min at 4°C. The supernatant was discarded and the pellet re-suspended using a Teflon-in- glass homogeniser in 20 volumes of fresh buffer and re-centrifuged as above. The final pellet was re-suspended using a Teflon-in-glass homogeniser to a tissue concentration of 1 g.ml ^'1 (original wet weight), and filtered through 500 μm pore- size Nytex mesh.

The membranes (400μl; containing 0.375μM PD 134, 308) were incubated for 150 minutes at 21 ± 3 ^* C in a final volume of 0.5ml with HEPES buffer containing [ ^l25 T]- CCK ₈ (S) (50μl; 200pM) and competing compound. Total and non-specific binding of [ ^,25 I]-CCK ₈ (S) were defined using 50μl of buffer and 50μl of lOOnM L-364,718 respectively. The assay was terminated by rapid filtration through pre-soaked Whatman GF/B filters using a Brandell Cell Harvester. The filters were washed (3 x 3ml) with ice-cold 50mM Tris HCl (pH 7.4 at 4°C) and bound radioactivity was determined by counting (1 min) in a gamma counter.

Table 1

Example pK, (Mouse cortex) pit, (Guinea pig pancreas)

I 5.0 6.7

2 5.9 7.3

3 5.1 6.5

4 5.0 5.5

5 5.0 5.3

6 5.0 5.3

7 5.0 5.8

8 5.0 6.0

9 5.4 6.5

10 5.6 6.5

II 6.0 5.3

12 5.0 5.0

13 5.6 5.5

14 5.6 5.5

15 5.9 5.8

16 5.8 5.7

17 5.9 5.2

18 5.5 5.4

19 5.1 4.8

20 5.5 5.4

21 5.1 5.2

-xample pit, (Mouse cortex) pit, (Guinea pig pancreas)

22 6.7 5.0

23 6.0 5.0

24 6.9 5.0

25 6.4 5.2

26 6.0 5.2

27 5.0 5.0

28 5.4 4.6

29 5.5 5.2

30 5.0 5.1

31 5.8 5.2

32 5.3 5.0

33 5.0 5.2

34 5.4 5.6

35 5.6 5.1

36 5.5 5.3

37 5.8 5.2

38 5.3 5.0

39 5.6 5.0

40 5.4 4.7

41 6.4 5.0

42 4.7 5.0

43 4.8 5.0

Example pit, (Mouse cortex) pK, (Guinea pig pancreas)

44 5.5 6.8

45 5.0 7.1

46 5.0 5.4

47 5.2

48 4.8

49 5.2

50 5.8 5.9

51 5.5 6.1

52 5.0 6.7

53 6.2

54 5.4

55 5.0 6.0

58 5.7 5.1

59 7.0 5.0

60 6.7 5.0

61 6.4 4.9

62 6.4

63 7.0 5.0

64 6.8 4.6

65 6.4

66 6.3

67 6.8

Example pit, (Mouse cortex) pit, (Guinea pig pancreas)

68 6.8

69 6.9

70 6.9

71 6.0 72 6.2

73 5.6

74 6.8

75 5.9