Field of the Invention

The present invention is directed to compounds and their pharmaceutically acceptable salts, which inhibit matrix metalloproteases, particularly stromelysin and matrilysin, and are therefore useful in the treatment of mammals having disease-states alleviated by the inhibition of such matrix metalloproteases.

BACKGROUND OF THE INVENTION Matrix metalloproteases are a family of proteases responsible for degradation and remodeling of connective tissues. Members of this family of enzymes share a number of properties, including zinc and calcium dependence, secretion as zymogens, and 40-50% amino acid sequence homology. The matrix metalloprotease family includes interstitial collagenaseε, derived from fibroblasts/macrophages and neutrophils, which catalyze the initial and rate-limiting cleavage of native collagen types I, II, III and X.

Collagen, the major structural protein of mammals, is an essential component of the matrix of many tissues, for example, cartilage, bone, tendon and skin. Interstitial collagenaεes are very specific matrix metalloproteases which cleave collagen to give two fragments which spontaneously denature at physiological temperatures and therefore become susceptible to cleavage by less specific enzymes. As cleavage by the collagenase results in the loss of structural integrity of the target tissue, it is essentially an irreversible process and therefore a good target for therapeutic intervention.

In addition to interstitial collagenases, the matrix metalloprotease family of enzymes include two distinct, but highly related, gelatinases: a 72-kD enzyme secreted by fibroblasts and a 92-kD enzyme release by mononuclear phagocytes. These gelatinases are capable of degrading gelatins (denatured collagens) , native collagen types IV and V, fibronectin and insoluble elastin.

The matrix metalloprotease family also includes εtromelysins 1 and 2, which are capable of cleaving a broad range of matrix substrates, including laminin, fibronectin, proteoglycans and collagen types IV and IX in their non-helical domains.

Matrilysin (putative metalloprotease or POMP) is a recently described member of the matrix metalloprotease family. Matrilysin is capable of degrading a wide range of matrix substrates including proteoglycans, gelatins, fibronectin, elastin, and laminin. Its expresεion haε been documented in mononuclear phagocytes, rate uterine explants and sporadically in tumors.

Inhibitors of matrix metalloproteases are considered to provide useful treatments for arthritic diseases, bone resorption disease (such as

osteoporosis) , the enhanced collagen destruction associated with diabetes, periodontal disease, corneal ulceration, ulceration of the skin, and tumor metastasis. For example, the design and potential use of collagenase inhibitors is described in J. Enzyme Inhibition (1987), Vol. 2, pp. 1-22, and in Drug News <_ Prospectives (1990), Vol. 3, No. 8, pp. 453-458. Matrix metalloprotease inhibitors are also the subject of various patents and patent applications, for example, U.S. Patent Nos. 5,189,178 (Galardy) and 5,183,900 (Galardy), European Published Patent Applications 0 438 223 (Beecham) and 0 276 436 (F. Hoffmann-La Roche) , Patent Cooperation Treaty International Applications 92/21360 (Merck) , 92/06966 (Beecham) and 92/09563 (Glycomed) .

SUMMARY OF THE INVENTION The invention provides new compounds which are useful as inhibitors of matrix metalloproteases, particularly stromelysin and matrilysin, and which are effective in treating disease-states characterized by excessive activity of matrix metalloproteases.

Accordingly, one aspect of the invention is directed to compounds of formula (I) :

wherein

R ¹ is mercapto, acetylthio, carboxy, hydroxycarbamoyl, alkoxycarbonyl, aryloxycarbonyl, aralkoxycarbonyl, benzyloxyaminocarbonyl or

(where R ⁶ is optionally substituted aryl, wherein the aryl group is quinol-2-yl, naphth-1-yl, naphth-2-yl, pyridyl or phenyl) ; R ² is alkyl, aralkyl or cycloalkylalkyl; R ³ is cycloalkyl, alkyl (optionally substituted by cycloalkyl, hydroxy, mercapto, alkylthio, aralkoxy, carboxy, amino, alkylamino, guanidino, carbamoyl, pyridyl or indolyl) , or aralkyl

(optionally substituted by hydroxy, carboxy, alkyl or alkoxy) ; R ⁴ is nitro, amino, cyano, hydroxy, alkoxy, carboxy, alkoxycarbonyl, alkylsulfonyl, haloalkyl, alkoxycarbonylalkyl, tetrazolyl, carbamoyl (optionally substituted by alkyl or dialkylaminoalkyl) , or aminosulfonyl (optionally substituted by

alkyl) ; and R ⁵ is hydrogen, halo or hydroxy; as a single stereoisomer or as a mixture thereof; or a pharmaceutically acceptable salt thereof.

Another aspect of the invention is directed to methods of inhibiting matrix metalloprotease activity in a mammal, which methods comprise administering to the mammal in need thereof a therapeutically effective amount of a compound of formula (I) as defined above, as a single stereoisomer, or as a mixture thereof, or a pharmaceutically acceptable salt thereof. Another aspect of the invention is directed to a pharmaceutical composition useful in inhibiting matrix metalloprotease activity in a mammal, which composition comprises a therapeutically effective amount of a compound of formula (I) as defined above, as a single stereoisomer or as a mixture thereof; or a pharmaceutically acceptable salt thereof; and a pharmaceutically acceptable excipient.

DETAILED DESCRIPTION OF THE INVENTION Definitions

As used in the specification and appended claims, unless specified to the contrary, the following terms have the meaning indicated:

"BOC" refers to t-butoxycarbonyl.

"CBZ" refers to benzyloxycarbonyl (carbobenzyloxy) .

"DMAP" refers to N, N-dimethylaminopyridine.

"DMF" refers to tv", i ^*" -dimethylformamide . "EDCI" refers to iV-ethyl-tv ^* ' - (3-dimethylaminopropyl) carbodiimide.

"HOBT" refers to 1-hydroxybenzotriazole.

"Hydroxy" refers to the radical -OH.

"Amino" refers to the radical -NR-.

"Acetylthio" refers to the radical -SC(0)CH ₃ . "Halo" refers to bromo, chloro or fluoro.

"Carbamoyl" refers to the radical -C(0)NH ₂ .

"Carboxy" refers to the radical -C(0)OH.

"Hydroxyamino" refers to the radical -NHOH.

"Hydroxycarbamoyl" refers to the radical -C(0)NHOH. "Mercapto" refers to the radical -SH.

"Benzyloxycarbamoyl" refers to -C(0)N(H)OCH ₂ C ₆ H ₅ .

"Alkyl" refers to a straight or branched chain monovalent radical consisting solely of carbon and hydrogen, containing no unsaturation and having from one to four carbon atoms, e.g. , methyl, ethyl, n-propyl, 2-methylpropyl (iso-butyl) , 1-methylethyl (iso-propyl) , n-butyl, and 1,1-dimethylethyl (t-butyl) , and the like.

"Alkylamino" refers to a radical of the formula -NHR_ where R_ is alkyl as defined above, e. g. , methylamino, ethylamino, iso-propylamino, n-butylamino, and the like. "Haloalkyl" refers to a radical of the formula -R_R_ where R_ is alkyl

as defined above substituted by one or more halo groups (R_) as defined above, e . g. , 2-chloroethyl, 2-bromoethyl, trifluoromethyl, and the like.

"Dialkylaminoalkyl" refers to a radical of the formula -R-N(R„) ₂ where each R_ is independently an alkyl radical as defined above, e . g. , dimethylaminoethyl, diethylamino-n-propyl, dimethylamino-n-propyl, and the like.

"Aminosulfonyl" refers to -SfCD-jNHj.

"Alkylsulfonyl" refers to a radical of the formula -S(0) ₂ R_ where R_ is alkyl as defined above, e . g. , methylsulfonyl, ethylsulfonyl, iso- propylsulfonyl, and the like.

"Alkylthio" refers to a radical of the formula -SR_ where R_ is alkyl as defined above, e.g. , methylthio, ethylthio, iso-propylthio, n-butylthio, and the like.

"Alkoxy" refers to a radical of the formula -OR_ wherein R_ is alkyl as defined above, e. g. , methoxy, ethoxy, n-propoxy, 1-methylethoxy, n-butoxy, t-butoxy, and the like.

"Alkoxycarbonylalkyl" refers to a radical of the formula -R-C(0)R _t , where R, is alkyl as defined above and R _t is alkoxy as defined above, e. g. , methoxycarbonylethyl, ethoxycarbonylethyl, methoxycarbonyl-iso-propyl, and the like.

"Aryl" refers to a quinol-2-yl, naphth-1-yl, naphth-2-yl or phenyl radical.

"Aryloxy" refers to a radical of the formula -ORj, wherein R,, is aryl as defined above, e . g. , phenoxy, quinol-2-yloxy, naphth-1-yloxy, or naphth- 2-yloxy.

"Aralkyl" refers to a radical of the formula -R_R_ wherein R_ is alkyl as defined above and R _t is aryl as defined above, e . g. , benzyl, phenylethylene, 3-phenylpropyl, 2-quinol-2-ylethyl, and the like.

"Aralkoxy" refers to a radical of the formula -OR_R_ wherein R_ is alkyl as defined above and R,, is aryl as defined above, e. g. , benzyloxy, 2-quinol-2-ylethoxy, 3-naphth-2-ylpropoxy, and the like.

"Alkoxycarbonyl" refers to a radical of the formula -C(0)R,, wherein _b is alkoxy as defined above, e. g. , methoxycarbonyl, ethoxycarbonyl, t-butoxycarbonyl, and the like. "Aralkoxycarbonyl" refers to a radical of the formula -C(0)R _c wherein

R_ is aralkoxy as defined above, e . g. , benzyloxycarbonyl, 2-quinol-2- ylethoxycarbonyl, and the like.

"Cycloalkyl" refers to a monovalent ring radical consisting solely of carbon and hydrogen atoms, containing no unsaturation and having from five to seven carbon atoms, e. g. , cyclopentyl, cyclohexyl and cycloheptyl.

"Cycloalkylalkyl" refers to a radical of the formula -R_R_ where R_ is alkyl as defined above and R_ is cycloalkyl as defined above, e . g. , cyclohexylmethyl, cyclohexylethyl, cyclopentylmethyl, cyclopentylmethyl, and the like.

"Phosphinoyl" refers to a radical of the formula H ₂ P(O) -, in which the 2 H atoms may be replaced by other groups.

"Optional" or "optionally" means that the subsequently described event of circumstances may or may not occur, and that the description includes instances where said event or circumstance occurs and instances in which it does not. For example, "optionally substituted quinol-2-yl" means that the quinol-2-yl radical may or may not be substituted and that the description includes both substituted quinol-2-yl radicals and quinol-2-yl radicals having no substitution. "Optionally substituted aryl" refers to a quinol-2-yl, naphth-1-yl, naphth-2-yl, pyridyl or phenyl radical optionally substituted by one or more εubstituents selected from the group consisting of halo, alkyl, alkoxy, hydroxy, and nitro, e.g. , 6-nitroquinol-2-yl, 6-fluoroquinol-2-yl, 6-hydroxyquinol-2-yl, 6-methoxyquinol-2-yl, 6-nitronaphth-l-yl, 6-chloronaphth-l-yl, 6-hydroxynaphth-l-yl, 6-methoxynaphth-l-yl, 6- nitronaphth-2-yl, 6-chloronaphth-2-yl, 6-hydroxynaphth-2-yl, 6- methoxynaphth-2-yl, 6-nitrophenyl, 6-chlorophenyl, 6-hydroxyphenyl, 6- methoxyphenyl, and the like.

"Amino-protecting group" as used herein refers to those organic groups intended to protect nitrogen atoms against undesirable reactions during synthetic procedures, and includes, but is not limited to, benzyl, acyl, acetyl, benzyloxycarbonyl (carbobenzyloxy) , p-methoxybenzyloxy- carbonyl, p-nitrobenzyloxycarbonyl, t-butoxycarbonyl, and the like.

"Pharmaceutically acceptable salt" refers to those salts which retain the biological effectiveness and properties of the free bases or free acids and which are not biologically or otherwise undesirable. If the compound exists as a free acid, the desired salt may be prepared by methods known to those of ordinary skill in the art, such as treatment of the compound with an inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid and the like; or with an organic acids such as acetic acid, propionic acid, glycolic acid, pyruvic acid, oxalic acid, maleic acid, malonic acid, εuccinic acid, fumaric acid, tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, methanesulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, salicylic acid, and the like. If the compound exiεts as a free base, the desired salt may also be prepared by methods known to those of ordinary skill in the art, such as the treatment of the compound with an inorganic base or an organic base. Salts derived from inorganic baseε include, but are not limited to, the εodium, potassium, lithium, ammonium, calcium, magnesium, iron, zinc, copper, manganese, aluminum salts and the like.

Salts derived from organic bases include, but are not limited to, salts of primary, secondary, and tertiary amines, subεtituted amineε including naturally occurring substituted amines, cyclic amines and basic ion exchange resins, such as isopropylamine, trimethylamine, diethylamine, triethyla ine, tripropylamine, ethanolamine, 2-dimethylaminoethanol,

2-diethylaminoethanol, trimethamine, dicyclohexylamine, lysine, arginine, histidine, caffeine, procaine, hydrabamine, choline, betaine, ethylenediamine, glucosamine, methylglucamine, theobromine, purineε, piperazine, piperidine, 2V-ethylpiperidine, polyamine resins and the like. "Mammal" includes humans and all domestic and wild animals, including, without limitation, cattle, horses, swine, sheep, goats, dogs, cats, and the like.

"Therapeutically effective amount" refers to that amount of a compound of formula (I) which, when administered to a mammal in need thereof, is sufficient to effect treatment, as defined below, for disease- states alleviated by the inhibition of matrix metalloprotease activity, particularly εtromelysin and matrilysin activity. The amount of a compound of formula (I) which conεtitutes a "therapeutically effective amount" will vary depending on the compound, the disease-state and its severity, and the mammal to be treated, but can be determined routinely by one of ordinary skill in the art having regard to his own knowledge and to this disclosure.

"Treating" or "treatment" as used herein cover the treatment of a disease-state in a mammal, particularly in a human, which disease-state is alleviated by the inhibition of matrix metalloproteaεe activity, particularly εtromelyεin and matrilysin activity, and the like; and include:

(i) preventing the disease-εtate from occurring in a mammal, in particular, when such mammal is predispoεed to the disease-state but has not yet been diagnosed as having it; (ii) inhibiting the disease-εtate, i.e., arresting its development; or

(iii) relieving the disease-state, i.e., causing regression of the disease-εtate.

"Stereoisomers" refers to compoundε having identical molecular formulae and nature or sequence of bonding but differing in the arrangement of their atoms in space.

The nomenclature used herein is basically a modified form of I.U.P.A.C. nomenclature wherein the compounds of the invention are named as peptide derivatives. The compounds of formula (I), or their pharmaceutically acceptable salts, have at least two asymmetric carbon atoms in their structure, and may therefore exist aε εingle stereoisomers, racemates, and as mixtures of enantiomers and diastereomers. All εuch single εtereoiεomerε, racemateε and mixtures thereof are intended to be within the scope of this invention. When naming the εingle stereoisomers of compounds of formula (I) an absolute descriptor, R or S, may be assigned to the chiral carbon atoms therein according to the "Sequence Rule" procedure of Cahn, Ingold and Prelog.

In addition, those sections of compounds of formula (I) which include R ³ , together with the adjacent nitrogen atom and carbonyl group, may define

an α-amino acid reεidue and are named as such.

For example, the following compound of formula (I) :

wherein R ¹ is hydroxycarbamoyl,- R ² is 2-methylpropyl; R ³ is 2-methylpropyl; R ⁴ is methoxycarbonyl; and R ⁵ is hydrogen; is named herein as 17- (4-methyl- 2- (N' '-hydroxycarbamoyl)methyl-pentanoyl) -L-leucine-W- (4-methoxycarbonyl- phenyl)carboxamide.

Utility and Administration A. Utility The compounds of formula (I) are useful in inhibiting mammalian matrix metalloproteases, particularly stromelysin and matrilysin, thereby preventing the degradation of collagen within the mammal. The compounds are therefore useful in treating diseaεe-εtateε which are asεociated with increased activity of matrix metalloproteaseε, particularly increaεed activity of εtromelyεin and matrilyεin, such as arthritis and osteoarthritiε, tumor metastasis, periodontal disease and corneal ulcerations. See, e.g. , Arthritis and Rheumatism (1993), Vol. 36, No. 2, pp. 181-189; Arttiritis and Rheumatism (1991), Vol. 34, No. 9, pp. 1073- 1075; Seminars in Arthritis and Rheumatism (1990), Vol. 19, No. 4, Supplement 1 (February), pp. 16-20; Drugs of the Future (1990), Vol. 15, No. 5, pp. 495-508; and J. Enzyme Inhibition (1987), Vol. 2, pp. 1-22.

B. Testing

The ability of the compounds of formula (I) to inhibit matrix metalloprotease activity, particularly stromelysin or matrilysin activity may be demonstrated by a variety of in vitro and in vivo assays known to those of ordinary skill in the art, such aε the assay described in Anal . Biochem. (1985), Vol. 147, p. 437, or modifications thereof.

C. General Administration

Administration of the compounds of formula (I) , or their pharmaceutically acceptable salts, in pure form or in an appropriate pharmaceutical composition, can be carried out via any of the accepted modes of administration or agents for εerving εimilar utilities. Thus, administration can be, for example, orally, nasally, parenterally,

topically, transdermally, or rectally, in the form of solid, semi-εolid, lyophilized powder, or liquid dosage forms, such as tablets, suppositories, pills, soft elastic and hard gelatin capsules, powders, solutions, εuεpenεionε, or aeroεolε, or the like, preferably in unit dosage formε suitable for εimple administration of precise dosages. The compositions will include a conventional pharmaceutical carrier or excipient and a compound of formula (I) as the/an active agent, and, in addition, may include other medicinal or pharmaceutical agents, carriers, adjuvants, etc. Generally, depending on the intended mode of administration, the pharmaceutically acceptable compositions will contain about 1% to about 99% by weight of a compound(s) of formula (I) , or a pharmaceutically acceptable εalt thereof, and 99% to 1% by weight of a suitable pharmaceutical excipient. Preferably, the composition will be about 5% to 75% by weight of a compound(s) of formula (I) , or a pharmaceutically acceptable salt thereof, with the rest being εuitable pharmaceutical excipient .

The preferred route of adminiεtration is oral, uεing a convenient daily doεage regimen which can be adjusted according to the degree of severity of the diseaεe-εtate to be treated. For such oral administration, a pharmaceutically acceptable composition containing a compound(ε) of formula (I) , or a pharmaceutically acceptable salt thereof, is formed by the incorporation of any of the normally employed excipientε, such as, for example, pharmaceutical grades of mannitol, lactose, starch, pre- gelatinized starch, magneεium εtearate, εodium εaccharine, talcum, cellulose ether derivativeε, glucoεe, gelatin, sucrose, citrate, propyl gallate, and the like. Such compositions take the form of solutions, suspenεionε, tabletε, pillε, capsules, powders, εustained releaεe formulations and the like.

Preferably such compositionε will take the form of capsule, caplet or tablet and therefore will also contain a diluent εuch aε lactose, sucrose, dicalcium phosphate, and the like; a diεintegrant such as croεcarmellose sodium or derivatives thereof; a lubricant such as magnesium stearate and the like; and a binder such as a starch, gum acacia, polyvinylpyrrolidone, gelatin, cellulose ether derivatives, and the like.

The compounds of formula (I) , or their pharmaceutically acceptable saltε, may alεo be formulated into a εuppository using, for example, about 0.5% to about 50% active ingredient disposed in a carrier that slowly dissolves within the body, e.g. , polyoxyethylene glycols and polyethylene glycolε (PEG), e.g. , PEG 1000 (96%) and PEG 4000 (4%).

Liquid pharmaceutically adminiεtrable compositionε can, for example, be prepared by diεsolving, diεpersing, etc. , a compound(s) of formula (I) (about 0.5% to about 20%), or a pharmaceutically acceptable salt thereof, and optional pharmaceutical adjuvants in a carrier, such as, for example, water, saline, aqueous dextrose, glycerol, ethanol and the like, to thereby form a solution or suεpenεion. If desired, a pharmaceutical composition of the invention may also

contain minor amounts of auxiliary subεtances such as wetting or emulsifying agents, Ph buffering agents, antioxidants, and the like, εuch aε, for example, citric acid, sorbitan monolaurate, triethanolamine oleate, butylated hydroxytoluene, etc. Actual methods of preparing such dosage forms are known, or will be apparent, to those skilled in this art; for example, see Remington 's Pharmaceutical Sciences, 18th Ed., (Mack Publishing Company, Easton, Pennsylvania, 1990) . The composition to be administered will, in any event, contain a therapeutically effective amount of a compound of formula (I) , or a pharmaceutically acceptable salt thereof, for treatment of a disease-state alleviated by the inhibition of matrix metalloprotease activity in accordance with the teachings of this invention.

The compounds of formula (I) , or their pharmaceutically acceptable salts, are administered in a therapeutically effective amount which will vary depending upon a variety of factors including the activity of the specific compound employed, the metabolic stability and length of action of the compound, the age, body weight, general health, sex, diet, mode and time of administration, rate of excretion, drug combination, the severity of the particular disease-state, and the host undergoing therapy. Generally, a therapeutically effective daily dose is from about 0.14 mg to about 14.3 mg/kg of body weight per day of a compound of formula (I), or a pharmaceutically acceptable salt thereof; preferably, from about 0.7 mg to about 10 mg/kg of body weight per day; and most preferably, from about 1.4 mg to about 7.2 mg/kg of body weight per day. For example, for administration to a 70 kg perεon, the dosage range would be from about 10 mg to about 1.0 gram per day of a compound of formula (I) , or a pharmaceutically acceptable salt thereof, preferably from about 50 mg to about 700 mg per day, and most preferably from about 100 mg to about 500 mg per day.

Preferred Embodiments

A preferred group of the compounds of formula (I) , as described above in the Summary of the Invention, are those compounds wherein R ¹ is mercapto or acetylthio. Within this group, a preferred subgroup of compoundε are thoεe compounds wherein R ² is alkyl, aralkyl, cycloalkylalkyl; R ³ is cycloalkyl or alkyl (optionally substituted by cycloalkyl, hydroxy, aralkoxy, alkylthio, pyridyl or indolyl) ; R ⁴ is cyano, carboxy, hydroxy, alkoxy, alkoxycarbonyl, alkoxycarbonylalkyl, carbamoyl (optionally substituted by aralkylaminoalkyl) , or aminosulfonyl (optionally substituted by alkyl) ; and R ⁵ is hydrogen.

Within this subgroup, a preferred class of compounds are those compounds wherein R ² is alkyl; R ³ is cyclohexyl, alkyl (optionally substituted by cyclohexyl, hydroxy, benzyloxy, methylthio, pyridyl or indolyl); and R ⁴ is carboxy, alkoxycarbonyl and aminosulfonyl.

Within this class of compounds, compounds wherein R ² is 2-methylpropyl are preferred. Particularly preferred are those compounds wherein R ³ is 2-methylpropyl.

Another preferred group of compounds of formula (I) , as described above in the Summary of the Invention, are those compounds wherein R ¹ is carbox .

Within this group, a preferred subgroup of compounds are those compounds wherein R ² is alkyl, aralkyl, cycloalkylalkyl; R ³ is cycloalkyl or alkyl (optionally εubstituted by cycloalkyl, hydroxy, aralkoxy, alkylthio, pyridyl or indolyl) ; R ⁴ iε cyano, hydroxy, alkoxy, carboxy, alkoxycarbonyl, alkoxycarbonylalkyl, carbamoyl (optionally subεtituted by aralkylamino¬ alkyl) , or aminoεulfonyl (optionally substituted by alkyl) ; and R ⁵ iε hydrogen.

Within this subgroup, a preferred claεε of compoundε are thoεe compounds wherein R ² iε alkyl; R ³ iε cyclohexyl, alkyl (optionally εubstituted by cyclohexyl, hydroxy, benzyloxy, methylthio, pyridyl or indolyl); and R ⁴ is carboxy, alkoxycarbonyl and aminosulfonyl.

Within this claεε of compoundε, preferred compoundε are those compounds wherein R ² is 2-methylpropyl. Particularly preferred are those compounds wherein R ³ is cyclohexyl, 2-methylpropyl, pyrid-3-ylmethyl, 1- benzyloxyethyl, l-methylpropyl, 1,1-dimethylethyl, 1-hydroxyethyl, and indol-2-ylmethyl; and R ⁴ is methoxycarbonyl.

Another preferred group of the compounds of formula (I) , as described above in the Summary of the Invention, are those compounds wherein R ¹ iε hydroxycarbamoyl.

Within this group, a preferred subgroup of compounds are those compounds wherein R ² is alkyl, aralkyl, cycloalkylalkyl; R ³ iε cycloalkyl or alkyl (optionally εubεtituted by cycloalkyl, hydroxy, aralkoxy, alkylthio, pyridyl or indolyl) ; R ⁴ iε cyano, hydroxy, alkoxy, carboxy, alkoxycarbonyl, alkoxycarbonylalkyl, carbamoyl (optionally εubstituted by aralkylamino¬ alkyl) , or aminoεulfonyl (optionally substituted by alkyl) ; and R ⁵ is hydrogen.

Within this subgroup, a preferred class of compounds are thoεe compounds wherein R ² is alkyl; R ³ is cyclohexyl, alkyl (optionally subεtituted by cyclohexyl, hydroxy, benzyloxy, methylthio, pyridyl or indolyl); and R ⁴ iε carboxy, alkoxycarbonyl and aminosulfonyl.

Within this class, preferred compounds are those compounds wherein R ² is 2-methylpropyl. Particularly preferred are those compounds wherein R ³ is cyclohexyl, 2-methylpropyl, pyrid-3-ylmethyl, 1-benzyloxyethyl, 1-methylpropyl, 1,1-dimethylethyl, 1-hydroxyethyl, and indol-2-ylmethyl.

Preεently, the most preferred compounds of formula (I) are the following: N- (4-methyl-2- (N' ' -hydroxycarbamoyl)methylpentanoyl) -

L-tryptophan-W- (4-carboxypheny1)carboxamide;

N- (4-methyl-2- (N' '-hydroxycarbamoyl)methylpentanoyl) -

L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (4-methyl-2- [N' '-hydroxycarbamoyl)methylpentanoyl) - L-leucine -N'- (4-carboxyphenyl) carboxamide; N- (4-methyl-2-mercaptomethylpentanoyl) -L-leucine- N ' - (4-methoxycarbonylpheny1) carboxamide; N- (4-methyl-2-acetylthiomethylpentanoyl) -L-leucine-

N' - (4-methoxycarbonylpheny1)carboxamide; N- (4-methyl-2-carboxymethylpentanoyl) -L-leucine- N ' - (4-methoxycarbonylpheny1)carboxamide;

N- (4-methyl-2- (N' '-hydroxycarbamoyl)methylpentanoyl) -

L-cyclohexylglycine-iV'- (4-methoxycarbonylphenyl)carboxamide; and N- (4-methyl-2- (N' '-hydroxycarbamoyl) ethylpentanoyl) -

L-1-leucine--/'- ( -methoxycarbonyl-phenyl)carboxamide.

Preparation of Compounds of Formula (I)

Compounds of formula (I) , as εingle stereoisomerε, or as mixtures thereof, and their pharmaceutically acceptable saltε, are peptide derivatives which can be prepared from the constituent α-amino acid derivative. Standard methods for the formation of peptide bonds are further illustrated by M. Bodanszky et al . , The Practice of Peptide Synthesis (1984) , Springer-Verlag; M. Bodanszky, Principles of Peptide Synthesis (1984), Springer-Verlag; J.P. Greenstein et al . , Chemistry of the Amino Acids (1961), Vol. 1-3, John Wiley and Sonε Inc.; G.R. Pettit, Synthetic Peptides (1970), Vol. 1-2, Van Noεtrand Reinhold Company. Amide couplings used to form the compounds of formula (I) are generally performed by the carbodiimide method with reagents such as dicyclohexylcarbodiimide or W-ethyl-Itf'- (3-dimethylaminoρropyl) - carbodiimide (EDCI) in the presence of l-hydroxybenzotriazole (HOBT) in an inert solvent such as dimethylformamide (DMF) . Other methods of forming the amide or peptide bond include, but are not limited to synthetic routes via an acid chloride, acyl azide, mixed anhydride or activated ester such as nitrophenyl ester. Typically, solution phase amide couplings with or without peptide fragments are performed. The selection of protecting groups for the terminal amino or carboxy groups of compoundε uεed in the preparation of the compounds of formula (I) is dictated in part by the particular amide or peptide coupling conditions, and in part by the amino acid and/or peptide components involved in the coupling. Amino-protecting groups commonly uεed include thoεe which are well-known in the art, for example, benzyloxycarbony1 (carbobenzyloxy) , p-methoxybenzyloxycarbonyl, p-nitrobenzyloxycarbonyl, t-butoxycarbonyl (BOO, and the like. It is preferred to use either BOC or benzyloxycarbony1 (CBZ) aε the protecting group for the o.-amino group because of the relative ease of its removal by mild acids, e.g. , by

trifluoroacetic acid (TFA) or hydrochloric acid in ethyl acetate; or by catalytic hydrogenation.

The individual stereoisomers of compounds of formula (I) may be separated from each other by methods known to those of ordinary skill in the art, e .g. , by selective cryεtallization or by chromatography, and/or by the methods disclosed herein.

Combinations of substituents and/or variables in compounds of formula (I) and intermediates thereof are permissible only if such combinations result in stable compounds.

A. Preparation of Compounds of Formula (E)

Compounds of formula (E) are intermediateε uεed in the preparation of compoundε of formula (I) , and are prepared as shown in the following Reaction Scheme 1 wherein R ² and R ⁶ are as defined above in the Summary of the Invention and R ¹² is meεyl or toεyl:

Reaction Scheme 1

(E_) (Eb) (Ec)

(Ee) (E)

Compounds of formula (Ea) may be prepared according to methods known to those of ordinary skill in the art (e.g., εee European Publiεhed Patent Application 0 276 436) or may be prepared according to the method described in Example 1 below. Compounds of formula (Ed) are commercially available or may be prepared according to methods known to those of ordinary skill in the art. In general, compounds of formula (E) are prepared by first treating a compound of formula (Ea) in an aprotic solvent, preferably tetrahydrofuran and methylene chloride, at 0-15°C, preferably at 0°C, in the presence of a base, preferably diisopropylethylamine and Jbis(trimethylsilyl)acetamide, with paraformaldehyde. The resulting εolution iε brought to 25-37°C, preferably to 37°C, for 18 hours. The compound of formula (Eb) iε then

iεolated by εtandard methodε, preferably by evaporation of solvent, extraction and filtration.

A compound of formula (Eb) in an aprotic solvent, preferably methylene chloride, is then cooled to -20°C to about 0°C, preferably to about -20°C. The compound of formula (Ec) is then eεterified by the εtandard procedure of treating the alcohol with at least a stoichiometric amount to about a 100% excess of either mesyl chloride or toεyl chloride, for a period of time, preferably for about 15 minuteε, at -20°C, followed by a period of time, preferably for about 3.5 hourε, at room temperature. The compound of formula (Ec) is then isolated from the reaction mixture by εtandard isolation procedures, preferably by extraction, filtration and evaporation.

A compound of formula (Ec) in an aprotic solvent, preferably DMF, is then reacted with a salt of a compound of formula (Ed) (preferably the sodium salt formed from the reaction of the compound of formula (Ed) with εodium hydride in an aprotic εolvent, preferably DMF) , for about 16-20 hourε, preferably for about 18 hourε, at temperatures beginning at about 0°C and slowly warming to room temperature. The resulting compound of formula (Ee) iε iεolated from the reaction mixture by εtandard isolation techniques, such as by extraction, evaporation, and flash chromatography.

A compound of formula (Ee) is then hydrolyzed under basic conditions, preferably in the preεence of εodium hydroxide, to form a compound of formula (E) , which iε iεolated from the reaction mixture by standard isolation techniques.

B. Preparation of Compounds of Formula (la)

Compounds of formula (la) are compoundε of formula (I) wherein R ¹ iε

where R ⁶ iε optionally substituted aryl, wherein the aryl group is quinol- 2-yl, naphth-1-yl, naphth-2-yl, pyridyl or phenyl; R ² is alkyl; R ³ is as described above in the Summary of the Invention; R ⁴ is as described above in the Summary of the Invention and R ⁵ is hydrogen. Compounds of formula (la) are prepared as described below in Reaction Scheme 2 where R ² is alkyl; R ³ is as described above in the Summary of the Invention; R ⁴ is as described above in the Summary of the Invention; R ⁵ is hydrogen; R* is aε deεcribed above and BOC iε t-butoxycarbonyl:

Reaction Scheme 2

(A)

W-protected amino acids of formula (A) and compounds of formula (B) are commercially available or may be prepared according to methods known to those of ordinary skill in the art. Compounds of formula (E) are prepared as shown above in Section A.

In general, compounds of formula (la) are prepared by first coupling a compound of formula (A) with a compound of formula (B) under standard amide coupling conditions to form a compound of formula (C) . For example,

to a cold (0-5°C) εolution of the compound of formula (A) and an excess molar amount of HOBT in DMF is added an excess molar amount of EDCI. The resulting solution is stirred from about 1 to about 2 hours, preferably for about 1 hour, at 0-5°C, preferably at 0°C. To the cold solution iε then added a εolution of an equimolar amount of a compound of formula (B) in the preεence of a base, preferably DMAP. The resulting mixture is stirred from 12 to 24 hours, preferably for 24 hours, at room temperature, preferably at 25°C. The compound of formula (C) is then iεolated from the reaction mixture by isolation techniques standard in the art of peptide chemistry, for example, evaporation, extraction, column chromatography and/or HPLC. The amino-protecting group of the compound of formula (C) is then removed under mild acidic conditions, preferably in the presence of trifluoroacetic acid, to yield a compound of formula (D) .

The compound of formula (D) so formed is then coupled with a compound of formula (E) under standard peptide coupling conditions. For example, to a cold (0-5°C, preferably 0°C) solution of the compound of formula (D) in an inert solvent, preferably THF, is added 1,1' -carbonyldiimidazole. The resulting mixture is εtirred from 60 to 90 minuteε, preferably for 75 minutes, at 0-5°C, preferably at 0°C, and then reacted with the compound of formula (E) for about 12 to 17 hours, preferably for about 15 hours. The resulting compound of formula (la) is then isolated from the reaction mixture by techniques standard is the peptide chemiεtry, for example, extraction and reverse phase HPLC.

C. Preparation of Compounds of Formula (F) Compounds of formula (F) :

0 R ²

R ^a -0C. 1^ ^ ^■ "^ C-0H

II o

(F)

where R ² iε aε defined above in the Summary of the Invention and R ⁸ is t-butyl, are intermediates in the preparation of compounds of formula (I) and are prepared aε shown in following Reaction Scheme 3 where R ² is as described above in the Summary of the Invention and R ⁸ is t-butyl:

Reaction Scheme 3

(fa) L-( + )-2 , 10-c amphor (Ft) suitam

L- ( +)-2 , 10-camphor suitam

In a similar manner, but substituting D- (-) -2,10-camphor εultam for L- (+) -2,10-camphor εultam, the corresponding individual stereoisomerε in the (S) configuration were prepared. Compounds of formula (Fa) are commercially available or may be prepared according to methods known to thoεe of ordinary skill in the art, for example, by the method described in Example 11 below. L- (+) -2,10- Camphor sultam and D- (-) -2,10-camphor εultam are commercially available, for example, from Aldrich Chemical Company, Milwaukee, Wisconsin, U.S.A. In general, compounds of formula (F) are prepared by first condensing a compound of formula (Fa) with L- (+) -2,10-camphor sultam to form a compound of formula (Fb) . Using NaHMDS to generate the anion for 1 hour, the reaction iε quenched with the t-butylbromoacetate to form the corresponding ester of formula (Q) . The camphor group is then removed under basic conditionε to yield an individual εtereoisomer of a compound of

formula (F) wherein the carbon to which the R ² substituent is attached is in the (R) configuration.

D. Preparation of Compounds of Formulae (lb), (Ic) , (Id) and (Ie) Compounds of formula (lb) are compounds of formula (I) wherein R ¹ is alkoxycarbonyl or aralkoxycarbonyl; and R ² , R ³ , R ⁴ and R ⁵ are as defined above in the Summary of the Invention.

Compounds of formula (Ic) are compounds of formula (I) wherein R ^! is carboxy; and R ² , R ³ , R ⁴ and R ⁵ are as defined above in the Summary of the Invention.

Compounds of formula (Id) are compounds of formula (I) wherein R ¹ is benzyloxycarbamoyl; and R ² , R ³ , R ⁴ and R ⁵ are as defined above in the Summary of the Invention.

Compounds of formula (Ie) are compounds of formula (I) wherein R ¹ is hydroxycarbamoyl; and R ² , R ³ , R ⁴ and R ⁵ are as defined above in the Summary of the Invention.

Compounds of formulae (lb) , (Ic) , (Id) and (Ie) are prepared as shown in following Reaction Scheme 4 wherein R ² , R ³ , R ⁴ , and R ⁵ are aε defined above in the Summary of the Invention; and R ⁸ iε t-butyl.

Reaction Scheme 4

(F)

Compounds of formula (F) are prepared as shown above in Section C. Compounds of formula (D) are prepared as shown above in Section B. 0-Benzylhydroxylamine iε commercially available, for example, aε the hydrochloride εalt from Aldrich Chemical Co.

In general, compoundε of formulae (lb) , (Ic) , (Id) and (Ie) are prepared by first coupling a compound of formula (F) with a compound of formula (D) under εtandard amide coupling conditionε to form a compound of formula (lb) . For example, to a solution of a compound of formula (F) in an aprotic solvent, preferably DMF, containing a εlightly excess molar amount of HOBT, is added an excess molar amount of EDCI. The resulting mixture is εtirred for about 1 to about 2 hours, preferably for about 1 hour, at 0-5°C, preferably at 0°C. To the cold solution is then added an equimolar amount of a compound of formula (D) in the presence of a base, preferably DMAP. The resulting mixture is then stirred for 12 to 24 hours, preferably for about 24 hours, at room temperature, preferably at about 25°C. The compound of formula (lb) iε then isolated from the reaction mixture by isolation techniques standard in the art of peptide chemistry, for example, evaporation of solvents, extraction, flash chromatography and/or HPLC.

The compound of formula (lb) is then hydrolyzed under mild acidic conditions, preferably with trifluoroacetic acid, to yield a compound of formula (Ic) .

The reεulting compound of formula (Ic) iε then treated with O- benzylhydroxylamine under standard amide coupling conditions to form a compound of formula (Id) . For example, a cold (0-5°C) solution of the compound of formula (Ic) and HOBT in an inert solvent, preferably DMF, is treated with an excess molar amount of EDCI. After stirring the resulting mixture for about 30 minutes to an hour at 0-5°C, preferably at 0°C, an equimolar amount of O-benzylhydroxyamine is added. The reaction mixture is allowed to warm to room temperature overnight. The compound of formula (Id) is then isolated from the reaction mixture by standard isolation techniques, for example, by extraction and flaεh chromatography.

The hydroxyl-protecting group (benzyl) of the compound of formula (Id) iε then removed under catalytic hydrogenation conditionε (Pd/C) to yield a compound of formula (Ie) .

E. Preparation of Compounds of Formula (6)

Compounds of formula (G) :

(6)

wherein R ² is as defined above in the Summary of the Invention, are intermediates in the preparation of compounds of formula (I) and are prepared as shown in the following Reaction Scheme 5 where R ² is as defined

above in the Summary of the Invention.

Reaction Scheme 5

CH3 _. CH-2O _n C _M COCH "→-CH- HO JL CH-CH, (G.)

(Ga)

(G)

Compoundε of formula (Ga) and thioacetic acid are commercially available, for example, from TCI America Organic Chemicalε and the Aldrich Chemical Company, reεpectively.

In general, a compound of formula (G) is prepared by first hydrolyzing a compound of formula (Ga) with an equimolar amount of a baεe, for example, potassium hydroxide, to yield a compound of formula (Gb) . The compound of formula (Gb) is then deprotonated under baεic conditions, for example, in the presence of triethylamine, at 0-5°C, preferably at 0°C, and then reacted with formaldehyde, followed by treatment with aqueouε baεe, preferably potassium carbonate, to yield a compound of formula (Gc) , which is isolated from the reaction mixture by standard isolation procedures.

The compound of formula (Gc) is then hydrolyzed under basic conditions, preferably in the presence of lithium hydroxide, to yield a compound of formula (Gd) . The compound of formula (Gd) iε then reacted with an excess molar amount of thioacetic acid at 90-100°C, preferably at

95°C, under an inert atmoεphere. The compound of formula (G) is then isolated from the reaction mixture by standard isolation techniques, for example, by extraction and evaporation.

F. Preparation of Compounds of Formulae (If) and (Ig) Compounds of formula (If) are compounds of formula (I) wherein R ¹ is acetylthio; and R ² , R ³ , R ⁴ and R ⁵ are as defined above in the Summary of the Invention.

Compounds of formula (Ig) are compounds of formula (I) wherein R ¹ iε mercapto; and R ² , R ³ , R ⁴ and R ⁵ are aε defined above in the Summary of the Invention.

Compounds of formulae (If) and (Ig) are prepared aε εhown in following Reaction Scheme 6 wherein R ² , R ³ , R ⁴ and R ⁵ are aε defined in the Summary of the Invention:

Reaction Scheme 6

(6) ( D :

(if)

(Ig)

Compounds of formula (D) are prepared aε εhown above in Section B. Compounds of formula (G) are prepared as shown above in Section E.

In general, compoundε of formulae (If) and (Ie) are prepared by first coupling a compound of formula (G) with a compound of formula (D) under standard amide coupling conditions to yield a compound of formula (If) . For example, to a solution of the compound of formula (G) and HOBT in an aprotic solvent, preferably DMF, is added an exceεs molar amount of EDCI. The resulting mixture is εtirred overnight at room temperature. The reεulting compound of formula (If) is then isolated from the reaction mixture by εtandard isolation techniques, for example, by evaporation of solvent, extraction, and flash chromatography. The compound of formula (If) is then hydrolyzed under baεic conditionε, preferably in a protic εolvent εuch aε methanol in the preεence of ammonium hydroxide, to form a compound of formula (Ig) .

In addition, all compounds of formula (I) that exist in either the

free acid or the free base form may be converted to their pharmaceutically acceptable salts by treatment with the appropriate inorganic or organic base or with the appropriate inorganic or organic acid, reεpectively. Saltε of the compounds of formula (I) can also be converted to the free acid or free baεe form or to another salt.

In summary, compounds of formulae (la) , (lb) , (Ic) , (Id) , (Ie) , (If) and (Ig) , which are all compounds of formula (I) , are prepared by:

1. reacting a compound of formula (D) where R ³ and R ⁴ are as defined above in the Summary of the Invention; and R ⁵ is hydrogen; with a compound of formula (E) where R ⁶ is optionally substituted aryl, wherein the aryl group is quinol-2-yl, naphth-1-yl, naphth-2-yl, pyridyl or phenyl; and R ² is alkyl; to form a compound of formula (la) wherein R ¹ is

0

II ^* R ⁶

QH

where R ⁶ is as defined above for the compound of formula (E) ,- and R ² , R ³ , R ⁴ , and R ⁵ are as defined above for the compounds of formulae (D) or (E) ; or

2. reacting a compound of formula (F) wherein R ² iε aε defined above in the Summary of the Invention; and R ⁸ iε alkyl or benzyl; with a compound of formula (D) wherein R ³ , R ⁴ and R ⁵ are aε defined above in the Summary of the Invention; to form a compound of formula (lb) wherein R ¹ iε alkoxycarbonyl or aralkoxycarbony1; and R ² , R ³ , R ⁴ , R ⁵ and R ⁸ are aε defined above for the compoundε of formulae (F) or (D) ; or

3. treating a compound of formula (lb) wherein R ² , R ³ , R ⁴ , and R ⁵ are aε defined above in the Summary of the Invention; and R ⁸ is alkyl or benzyl; to form a compound of formula (Ic) wherein R ¹ is carboxy; and R ² , R ³ , R ⁴ , and R ⁵ are as defined above in the Summary of the Invention; or

4. reacting a compound of formula (Ic) wherein R ² , R ³ , R ⁴ , and R ⁵ are aε defined above in the Summary of the Invention; with O- benzylhydroxyamine to form a compound of formula (Id) wherein R ¹ iε benzyloxycarbamoyl; and R ² , R ³ , R ⁴ , and R ⁵ are aε defined above in the Summary of the Invention; or

5. treating a compound of formula (Id) wherein R ² , R ³ , R ⁴ , and R ⁵ are aε defined above in the Summary of the Invention; to form a compound of formula (Ie) wherein R ¹ hydroxycarbamoyl; and R ² , R ³ , R ⁴ , and R ⁵ are as defined above in the Summary of the Invention; or 6. reacting a compound of formula (G) wherein R ² iε aε defined above in the Summary of the Invention; with a compound of formula (D) wherein R ³ , R ⁴ and R ⁵ are as defined above in the Summary of the Invention; to form a compound of formula (If) wherein R ¹ iε acetylthio; and R ² , R ³ , R ⁴ and R ⁵ are as defined above in the Summary of the Invention; or

7. treating a compound of formula (If) wherein R ² , R ³ , R ⁴ and R ⁵ are as defined above in the Summary of the Invention; to form a compound of formula (Ig) wherein R ¹ is mercapto; and R ² , R ³ , R ⁴ and R ⁵ are aε defined above in the Summary of the Invention.

The following specific preparations and examples are provided as a guide to assist in the practice of the invention, and are not intended as a limitation on the scope of the invention.

Example 1

Compounds of formula (Ea)

A. Crystalline phosphinic acid (8.4 g, 0.13 mol) was stirred in neat triethylorthoformate (22 mL, 0.20 mL) for 90 minutes at room temperature. This was then transferred via cannula to a stirred εolution of ethyliεobutylacrylate (8 g, 0.036 mol) and tetramethylguanidine (4.5 mL, 0.036 mol) that had been cooled to 0°C for 10 minuteε. The ice bath was removed and the reaction stirred for 4 hours. The mixture was diluted with 200 mL of diethyl ether and the solution washed with 1 N HC1 (100 mL) , water (4x100 mL) , brine (100 mL) , and dried over magnesium sulfate. This was rotary-evaporated to yield 8.15 g of 2- (ethoxy)phosphinoylmethyl-4- methylpentanoic acid ethyl ester aε a slightly yellow colored oil, MS: 349 (M- H ₂ 0) ⁺ .

B. In a similar manner, the following compounds of formula (Ea) are prepared: 2- (ethoxy)phosphinoylmethyl-5-phenylpentanoic acid ethyl ester; 2- (ethoxy)phoεphinoylmethyl-4-phenylbutanoic acid ethyl ester; 2- (ethoxy)phosphinoylmethyl-3-phenylpropanoic acid ethyl ester;

2- (ethoxy)phosphinoylmethyl-3-cyclohexylpropanoic acid ethyl eεter; and 2- ( (ethoxy)phosphinoylmethyl)pentanoic acid ethyl ester.

Example 2

Compound of formula (Eb) A. Crude 2- (ethoxy)phosphinoylmethyl-4-methylpentanoic acid ethyl ester (26 g) was diεεolved in 600 mL THF/CH ₂ C1 ₂ (50/50) and cooled to 0°C. N,N-diisopropylethylamine (32 mL) and 90.8 mL of bis- (trimethylsilyl) acetamide were added to the solution and the resulting mixture was stirred for 20 minutes and then paraformaldehyde (5.5 g) was added. The solution was brought to room temperature and heated at 37°C for 18 hours. The solvent was removed by evaporation, and the resulting oil diεsolved in 200 mL ethyl acetate. The solution was washed with 50 mL of IN HC1 (2x) , 50 mL of brine (2x) , dried over MgS0 ₄ , filtered and evaporated to yield

19.3 g of 2- (ethoxy) (hydroxymethyl)phoεphinoylmethyl-4-methylpentanoic acid ethyl ester as a faintly yellow oil, MS: 281.2 (MH ⁺ ) .

B. In a similar manner, the following compounds of formula (Eb) are prepared: 2- (ethoxy) (hydroxymethyl)phosphinoylmethyl-5-phenylpentanoic acid ethyl ester; 2- (ethoxy) (hydroxymethyl)phosphinoylmethyl-4-phenylbutanoic acid ethyl ester; 2- (ethoxy) (hydroxymethyl)phoεphinoylmethyl-3-phenylpropanoic acid ethyl ester;

2- (ethoxy) (hydroxymethyl)phosphinoylmethyl-3-cyclohexyl- propanoic acid ethyl ester; and 2- ((ethoxy) (hydroxymethyl)phosphinoylmethyDpentanoic acid ethyl ester.

Example 3 Compounds of formula (Ec)

A. 2- (Ethoxy) (hydroxymethyl)phosphinoylmethyl-4-methylpentanoic acid ethyl eεter (5 g) was disεolved in 20 mL of CH ₂ C1 ₂ and cooled to -20°C (in duplicate). Methanesulfonyl chloride (1.5 mL) and triethylamine (3.0 mL) were added dropwise to the εolution. After 15 minutes the bath was removed and the reaction left at room temperature for 3"_ hourε. Each εolution waε then washed with 10 mL cold 2% HC1, 10 mL NaHC0 ₃ (sat) , 10 mL brine, dried with MgS0 ₄ , filtered and evaporated to yield 12.8 g (combined yield) of 2- (ethoxy) (methanesulfonyloxymethyl)phoεphinoylmethyl-4- methylpentanoic acid ethyl ester.

B. In a similar manner, but replacing methanesulfonyl chloride with p-toluenesulfonyl chloride, 2- (ethoxy) - (p-toluenesulfonyloxymethyl) - phosphinoylmethyl-4-methylpentanoic acid ethyl ester iε prepared. C. In a εimilar manner, the following compoundε of formula (Ec) are prepared: 2- (ethoxy) (methanesulfonyloxymethyl)phosphinoylmethyl-

5-phenylpentanoic acid ethyl ester; 2- (ethoxy) (methanesulfonyloxymethyl)phosphinoylmethyl- 4-phenylbutanoic acid ethyl ester;

2- (ethoxy) (methanesulfonyloxymethyl)phosphinoylmethyl-

3-phenylpropanoic acid ethyl ester; 2- (ethoxy) (methanesulfonyloxymethyl)phoεphinoylmethyl- 3-cyclohexylpropanoic acid ethyl ester; 2- ( (ethoxy) (methanesulfonyloxymethyl)phosphinoylmethyl) - pentanoic acid ethyl ester; 2- (ethoxy) (p-toluenesulfonyloxymethyl)phosphinoylmethyl-

5-phenylpentanoic acid ethyl ester; 2- (ethoxy) (p-toluenesulfonyloxymethyl)phosphinoylmethyl- 4-phenylbutanoic acid ethyl ester;

2- (ethoxy) (p-toluenesulfonyloxymethyl)phoεphinoylmethyl-

3-phenylpropanoic acid ethyl ester; 2- (ethoxy) (p-toluenesulfonyloxymethyl)phoεphinoylmethyl-

3-cyclohexylpropanoic acid ethyl ester; and 2- ( (ethoxy) (p-toluenesulfonyloxymethyl)phosphinoylmethyl) - pentanoic acid ethyl ester.

Example 4

Compounds of formula (Ee) Sodium hydride (1.52 g, (60%)) and 2-quinolinethiol (6 g) were stirred together at 0°C in 50 mL DMF. After the initial H ₂ evolution had subsided, the mixture was stirred at room temperature for 2.5 hours. The mixture was then cooled to 0°C and 2- (ethoxy) (methanesulfonyloxymethyl) - phosphinoylmethyl-4-methylpentanoic acid ethyl ester (12.8 g) in 10 mL DMF was added via cannula. The resulting mixture was εtirred for 18 hourε, slowly warming to room temperature. The DMF was removed by evaporation, the residue dissolved in 50 mL ethyl acetate and washed with 50 mL H ₂ 0 (2x) , brine (50 mL) , dried over MgS0 ₄ and evaporated to a yellow semi- solid. Purification by flash chromatography using 10% ethyl acetate/hexane to 80% ethyl acetate/hexane for the elution yielded 10 g of 2- (ethoxy) - (quinolin- -ylthiomethyl)phosphinoylmethyl-4-methylpentanoic acid ethyl ester (Rf 0.35 80% ethyl acetate/hexane) , MS: 424.1 (MH ⁺ ) .

B. In a similar manner, but replacing 2-quinolinethiol with 1-naphthalenethiol, 2-naphthalenethiol or thiophenol, the following compounds of formula (Ee) are prepared:

2- (ethoxy) (naphth-1-ylthiomethyl)phosphinoylmethyl-

4-methylpentanoic acid ethyl ester; 2- (ethoxy) (naphth-2-ylthiomethyl)phosphinoylmethyl- 4-methylpentanoic acid ethyl ester; and 2- (ethoxy) (phenylthiomethyl)phosphinoylmethyl- 4-methylpentanoic acid ethyl eεter.

C. In a εimilar manner, the following compoundε of formula (Ee) are prepared:

2- (ethoxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl- 5-phenylpentanoic acid ethyl eεter;

2- (ethoxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl-

4-phenylbutanoic acid ethyl ester; 2- (ethoxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl- 3-phenylpropanoic acid ethyl ester; 2- (ethoxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl- 3-cyclohexylpropanoic acid ethyl ester; 2- ( (ethoxy) (quinoιin-2-ylthiomethyl)phoεphinoylmethyl) - pentanoic acid ethyl eεter; 2- (ethoxy) (naphth-l-ylthiomethyl)phoεphinoylmethyl- 5-phenylpentanoic acid ethyl ester;

2- (ethoxy) (naphth-1-ylthiomethyl)phosphinoylmethyl-

4-phenylbutanoic acid ethyl ester; 2- (ethoxy) (naphth-l-ylthiomethyl)phosphinoylmethyl-

3-phenylpropanoic acid ethyl ester; 2- (ethoxy) (naphth-l-ylthiomethyl)phosphinoylmethyl-

3-cyclohexylpropanoic acid ethyl eεter; 2- ( (ethoxy) (naphth-1-ylthiomethyl)phoεphinoylmethyl) - pentanoic acid ethyl eεter; 2- (ethoxy) (naphth-2-ylthiomethyl)phoεphinoylmethyl- 5-phenylpentanoic acid ethyl eεter;

2- (ethoxy) (naphth-2-ylthiomethyl)phoεphinoylmethyl-

4-phenylbutanoic acid ethyl ester; 2- (ethoxy) (naphth-2-ylthiomethyl)phosphinoylmethyl-

3-phenylpropanoic acid ethyl ester; 2- (ethoxy) (naphth-2-ylthiomethyl)phosphinoylmethyl-

3-cyclohexylpropanoic acid ethyl ester; 2- ( (ethoxy) (naphth-2-ylthiomethyl)phoεphinoylmethyl) - pentanoic acid ethyl ester; 2- (ethoxy) (phenylthiomethyl)phosphinoylmethyl- 5-phenylpentanoic acid ethyl ester;

2- (ethoxy) (phenylthiomethyl)phosphinoylmethyl-

4-phenylbutanoic acid ethyl eεter; 2- (ethoxy) (phenylthiomethyl)phoεphinoylmethyl-

3-phenylpropanoic acid ethyl eεter; 2- (ethoxy) (phenylthiomethyl)phoεphinoylmethyl-

3-cyclohexylpropanoic acid ethyl eεter; and 2- ( (ethoxy) (phenylthiomethyl)phosphinoylmethyl) - pentanoic acid ethyl ester.

Example 5

Compounds of formula (E)

A. 2- (Ethoxy) (quinolin-2-ylthiomethyl)phosphinoyl-methyl-4- methylpentanoic acid ethyl ester (4.5 g) was dissolved in 100 mL THF and 12.5 mL of 2N NaOH was added together with enough methanol to make the solution homogeneous. After 18 hours the THF was removed by evaporation, the residue diluted with 50 mL ^O and waεhed with 50 mL ethyl acetate. The aqueouε phase was then acidified to pH 4, and the product extracted with 50 mL ethyl acetate (2x) . The ethyl acetate was waεhed with 20 mL brine, dried with MgS0 ₄ and evaporated to yield 3.8 g of 2- (hydroxy) - (quinolin-2-ylthiomethyl)phoεphinoylmethyl-4-methylpentanoi c acid aε a yellow oil, MS: 368 (MH ⁺ ) .

B. In a εimilar manner, the following compoundε of formula (E) are prepared:

2- (hydroxy) (naphth-1-ylthiomethyl)phoεphinoylmethyl- 4-methylpentanoic acid;

2- (hydroxy) (naphth-2-ylthiomethyl)phosphinoylmethyl-

4-methylpentanoic acid; and 2- (hydroxy) (phenylthiomethyl)phosphinoylmethyl-

4-methylpentanoic acid. C. In a similar manner, the following compounds of formula (E) are prepared: 2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-

5-phenylpentanoic acid; 2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl- 4-phenylbutanoic acid;

2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-

3-phenylpropanoic acid; 2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-

3-cyclohexylpropanoic acid; 2- ((hydroxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl) - pentanoic acid; 2- (hydroxy) (naphth-1-ylthiomethyl)phosphinoylmethyl-

5-phenylpentanoic acid; 2- (hydroxy) (naphth-1-ylthiomethyl)phoεphinoylmethyl- 4-phenylbutanoic acid;

2- (hydroxy) (naphth-l-ylthiomethyl)phoεphinoylmethyl-

3-phenylprop_uιoic acid; 2- (hydroxy) (naphth-1-ylthiomethyl)phosphinoylmethyl-

3-cyclohexylpropanoic acid; 2- ((hydroxy) (naphth-l-ylthiomethyl)phosphinoylmethyl) - pentanoic acid; 2- (hydroxy) (naphth-2-ylthiomethyl)phosphinoylmethyl-

5-phenylpentanoic acid; 2- (hydroxy) (naphth-2-ylthiomethyl)phosphinoylmethyl- 4-phenylbutanoic acid;

2- (hydroxy) (naphth-2-ylthiomethyl)phoεphinoylmethyl-

3-phenylpropanoic acid; 2- (hydroxy) (naphth-2-ylthiomethyl)phoεphinoylmethyl-

3-cyclohexylpropanoic acid; 2- ((hydroxy) (naphth-2-ylthiomethyl)phoεphinoylmethyl) - pentanoic acid; 2- (hydroxy) (phenylthiomethyl)phoεphinoylmethyl-

5-phenylpentanoic acid; 2- (hydroxy) (phenylthiomethyl)phosphinoylmethyl- 4-phenylbutanoic acid;

2- (hydroxy) (phenylthiomethyl)phosphinoylmethyl-

3-phenylpropanoic acid; 2- (hydroxy) (phenylthiomethyl)phosphinoylmethyl-

3-cyclohexylpropanoic acid; and 2- ((hydroxy) (phenylthiomethyl)phoεphinoylmethyl)pentanoic acid.

Example 6 Resolution of a compound of formula (E) 2- (Hydroxy) (quinolin-2-ylthiomethyl)phosphinoyl-methyl-4- methylpentanoic acid (5.3 g) was dissolved in 50 mL of warm ethanol (abs) and 4.2 g of (-) -cinchonidine was added. After 30 minutes at room temperature the salt began to precipitate out. The flask was covered in foil and allowed to stand for 2 days. The salt was then removed by suction filtration, and the filtrate evaporated to a yellow foam. The εalt and the filtrate were each diεsolved in 100 mL ethyl acetate and washed successively with 1% HC1 to remove the cinchonidine while keeping the pH above 4. Both solutions were each dried over MgS0 ₄ and evaporated to yield 2.4 g of a single stereoisomer, [c.] "=+10.68° (9.73 mg in methanol (2 mL) ) and 2.5 g of the other single stereoisomer, [c.]£ ⁴ =-8.70 ^o (9.88 mg in methanol (2 mL) ) .

Example 7 Compounds of formula (B)

A. To a cold (0°C) suspenεion of 4-acetamidobenzenesulphonyl chloride (4.0 g, 17 mmol) in Cϊ^C^ (40 mL) was added pyridine (1.7 mL, 20 mmol) and DMAP (209 mg, 1.7 mmol) . A clear εolution resulted. Anhydrous methylamine was bubbled into the solution for 1 hour at 0°C, and then the solution was allowed to εtir at 25°C for 2 hours. The solution was extracted with IM NaOH (3x15 mL) and the combined extractε were adjusted to pH 6 at 0°C with 3M HC1. The product, which precipitated aε fluffy white crystals, was filtered and washed with cold water to afford 3.2 g (82%) of 4-acetamido-iV-methylbenzenesulphonamide; Η NMR (300 MHz, MeOH) δ 2.35 (s,3H), 2.70 (s,3H), 7.96 (s,4H).

B. A mixture of 4-acetamido-_-methylbenzeneεulphonamide (3.2 g, 14 mmol) and 100 mL of IM HC1 waε refluxed under argon for 3 hourε. After cooling to 25°C, (10 mL) was added and the aqueous phase was neutralized with IM NaOH at 0°C. The aqueous phase waε εeparated and extracted with CH-C1 ₂ (2x25 mL) . The combined organic phases were washed with brine (10 mL) , dried (NajSO,,) and concentrated to afford 1.5 g (58%) of a compound of formula (B) where R ⁴ is W-methylsulfonamide as a colorlesε solid; Η NMR (300 MHz, MeOH) δ 2.46 (s,3H), 6.67-6.72 (AA ¹ part of AA'XX ¹ 2H) , 7.48-7.52 (XX ¹ part of AA'XX ¹ , 2H) .

Example 8 Compounds of formula (C) A. To a cold (0°C) εolution of N-tert-butoxycarbonyl-L-leucine

(1.4 g, 6.3 mmol) and HOBT (1.5 g, 9.8 mmol) in DMF (30 mL) was added EDCI (2.5 g, 14 mmol) in portions. After εtirring for 1 hour at 0°C, the ' reεulting εolution was treated with methyl 4-aminobenzoate (1.09 mL, 6.8 mmol) and DMAP (0.32 g, 2.6 mmol). After stirring for 24 hours at 25°C,

the DMF was removed in vacuo . The residue waε dissolved in CH ₂ C1 ₂ and washed with saturated NaHC0 ₃ εolution, IM HC1 (twice), and brine. Drying over Na ₂ S0 ₄ and concentration in vacuo afforded the crude product which waε purified by flash chromatography on Si0 ₂ (20% ethyl acetate/hexanes eluent) . There was obtained 1.0 g (85%) of N-t-butoxycarbonyl-L-leucine-

N' - (4-methoxycarbonylphenyl) carboxamide as a foamy solid, MS (FAB) 363 (M- H)\

B. In a similar manner, the following compounds of formula (C) were prepared: N-t-butoxycarbonyl-L-tryptophan-.W-phenylmethy1carboxamide;

N-t-butoxycarbonyl-L-tryptophan- N'-phenylcarboxamide;

N-t-butoxycarbonyl-L-tryptophan -N ' - (4-methoxycarbonylphenyl) carboxamide; N- t-butoxycarbony1-L-tryptophan- N '- (4-ethoxycarbonylpheny1) carboxamide,- N-t-butoxycarbonyl-L-leucine-W- (4- {N' '-methylaminoεulfonyl)phenyl) - carboxamide;

N-t-butoxycarbonyl-L-alanine-W- (4-methoxycarbonylphenyl) carboxamide; N-t-butoxycarbonyl-L-methionine-W- (4-methoxycarbonylphenyl) carboxamide,- N-t-butoxycarbonyl-L-leucine -N' - (3-ethoxycarbonylphenyl) carboxamide,- N-t-butoxycarbonyl-L-leucine- N' - (2-methoxycarbonylphenyl) carboxamide; N-t-butoxycarbonyl-L-leucine-W- (4- (1-methylethyloxy) carbony1)phenyl) - carboxamide; N-t-butoxycarbonyl-L-leucine -N' - (aminosulfonyl)phenyl) carboxamide; N-t-butoxycarbonyl-L-leucine -N'- (4-methoxycarbonylmethylphenyl) - carboxamide; N- t-butoxycarbonyl-L-pyridin-3-ylalanine-W- ( -methoxycarbonylphenyl) - carboxamide; N- t-butoxycarbony1-L-cyclohexylglycine -N' - (4-methoxycarbonylphenyl) - carboxamide; N-t-butoxycarbonyl-L-isoleucine-W- (4-methoxycarbonylphenyl) carboxamide; N-t-butoxycarbonyl-L-O-benzylthreonine-W- (4-methoxycarbonylphenyl) - carboxamide; N-t-butoxycarbonyl-L-t-leucine -N' - (4-methoxycarbonylphenyl) carboxamide; N-t-butoxycarbonyl-L-leucine-W- (4-cyanophenyl) carboxamide; N-t-butoxycarbonyl-L-leucine -N' - (4- (N' ' - (2-dimethylaminoethylcarbamoyl) - carboxamide; and

N-t-butoxycarbonyl-L-leucine-W- (4- [N' ' - (3-dimethylaminopropyl) carbamoyl) - phenyl)carboxamide.

C. In a similar manner, the following compounds of formula (C) are prepared: N-t-butoxycarbonyl-L-tryptophan-W*- ( -nitrophenyl) carboxamide; N- t-butoxycarbony1-L-tryptophan -N' - (4-aminophenyl) carboxamide; N-t-butoxycarbonyl-L-leucine -N' - (4-methylsulfonylphenyl) carboxamide;

N-t-butoxycarbonyl-L-leucine -N' - (4-ethylsulfonylphenyl) carboxamide; and N-t-butoxycarbonyl-L-leucine -N' - (4-tetrazolylphenyl) carboxamide.

Example 9 Compounds of formula (D)

A. To a cold (0°C) εolution of N-t-butoxycarbonyl-L-leucine-W- phenylcarboxamide (3.4 g, 11 mmol) in dry CH _j Cl _j (10 mL) was added TFA

(2 mL) . The solution was allowed to stir at 25°C for 6 hours and was then concentrated in vacuo. The residue was partitioned between CH ₂ C1 ₂ and H ₂ 0 and the aqueous layer was baεified at 0°C with saturated K ₂ CO ₃ solution.

The organic phaεe waε separated and the aqueous layer was extracted three times with CH-C1 ₂ . The combined organic layers were waεhed with brine and dried over Na ₂ S0 ₄ . Concentration afforded L-leucine- -phenylcarboxamide.

B. In a similar manner, the following compounds are prepared: L-leucine-W- (4-methoxycarbonylphenyl) carboxamide;

L-tryptophan-W-phenylmethy1carboxamide;

L-tryptophan- N ' -phenylcarboxamide,-

L-tryptophan-W- (4-methoxycarbonylphenyl) carboxamide;

L-tryptophan-W- (4-ethoxycarbonylphenyl) carboxamide; L-leucine- N' - (4- (N' '-methylaminosulfonyl)phenyl) carboxamide;

L-alanine-W- (4-methoxycarbonylphenyl) carboxamide;

L-methionine-W- (4-methoxycarbonylphenyl) carboxamide;

L-leucine-W- (3-ethoxycarbonylphenyl) carboxamide;

L-leucine-W- (2-methoxycarbonylphenyl) carboxamide; L-leucine-W- (4- (1-methylethyloxy)carbonyl)phenyl)carboxamide;

L-leucine-W- (aminosulfonyl)phenyl) carboxamide;

L-leucine-W- (4-methoxycarbonylmethylphenyl) carboxamide;

L-pyridin-3-ylalanine-W- (4-methoxycarbonylphenyl) carboxamide;

L-εpirocyclopentylglycine-W- (4-methoxycarbonylphenyl) carboxamide; L-cyclohexylglycine-W- (4-methoxycarbonylphenyl) carboxamide;

L-iεoleucine-W- (4-methoxycarbonylphenyl) carboxamide;

L-O-benzylthreonine-W- (4-methoxycarbonylphenyl)carboxamide,-

L-t-leucine-W- (4-methoxycarbonylphenyl) carboxamide;

L-leucine-W- (4-cyanophenyl)carboxamide; L-leucine-W- (4- (W '- (2-dimethylaminoethyl) carbamoyl) henyl) carboxamide; and

L-leucine-W- (4- (W '- (3-dimethylaminopropyl) carbamoyl)phenyl) carboxamide.

C. In a εimilar manner, the following compounds of formula (D) are prepared: L-tryptophan-W- (4-nitrophenyl) carboxamide, ^• L-tryptophan-W- (4-aminophenyl)carboxamide; L-leucine-W- (4-methylsulfonylphenyl) carboxamide;

L-leucine-W- (4-ethylsulfonylphenyl) carboxamide; and L-leucine-W- (4-tetrazolylphenyl) carboxamide.

Example 10 Compounds of formula (la)

A. To a cold (0°C) solution of 2- (hydroxy) (quinolin-2-ylthio¬ methyl)phoεphinoylmethyl-4-methylpentanoic acid (0.20 g, 0.54 mmol) in THF

(6 mL) waε added 1,1 ' -carbonyldiimidazole (0.12 g, 0.7 mmol) . The mixture waε εtirred for 75 minuteε at 0°C and waε then treated with L-tryptophan- W- (4-ethoxycarbonylphenyl) carboxamide (0.22 g, 0.62 mmol) and εtirred at

25°C for 15 hourε. The THF was evaporated and the residue waε dissolved in ethyl acetate (60 mL) . The εolution was washed with H ₂ 0 (10 mL) , brine (10 mL) , and dried over MgS0 ₄ . Concentration was followed by reverse phase HPLC using a gradient of acetonitrile and 50 mM NH ₄ 0Ac buffer afforded 30 mg of N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phosphinoyl-methyl-4- methylpentanoyl) -L-tryptophan-W- (4-ethoxycarbonylphenyl) carboxamide as an off white solid, MS (FAB) 701 (M-H) ⁺ (mixture of diaεtereomers) .

B. In a similar manner, the following compounds of formula (la) were prepared: N- (2- (hydroxy) (qumolin-2-ylthiomethyl)phosphinoylmethyl-4-methylpentanoyl) -L-tryptophan-W- (4-methoxycarbonylphenyl) carboxamide, MS (FAB) 687 (M+H) ⁺ ; N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-4-methylpentanoy l) -L-alanine-W- (4-methoxycarbonylphenyl) carboxamide, MS (FAB) 572 (M+H) ⁺ ;

N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-4-methylpentanoy l) -L-methionine-W- (4-methoxycarbonylphenyl) carboxamide, MS (FAB) 632 (M+H) ⁺ ; Compound 1 N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl-4-methylpentanoyl ) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide,

MS (FAB) 614 (M+H) ⁺ ; N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-4-methylpentanoy l) -L-leucine-W- (3-ethoxycarbonylphenyl)carboxamide,

Η NMR (300 MHz, MeOH) δ 0.73-1.01 (m, 12H) , 1.28-2.00 (m, 14H) , 2.4- 3.61 (m, 2H) , 4.27-4.45 ( , 3H) , 7.23-7.44 (m, 3H) , 7.65-7.98 (m,

6H) , 8.29 (ε, 0.5H), 8.50 (s, 0.5H); N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl4-methylpentanoyl) -L-leucine-W- (2-methoxycarbonylphenyl) carboxamide,

'H NMR (300 MHz, MeOH) δ 0.78-0.99 (m, 13H) , 1.3-2.4 (m, 7H) , 2.90- 3.05 (m, 1H) , 3.5-3.75 (m, 2H) , 3.89, 3.90, 3.94 (3s, 3H total) ,

4.35-3.50 (m, 1H) , 7.05-8.10 (m, 11H) , 8.32, 8.55, 8.60 (3d, J=8.7, 1H) ; N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl-

4-methylpentanoyl) -L-leucine-W- (4- (1,1-dimethylethoxycarbonyl- phenyl)carboxamide, MS(FAB) 642 (MH) ⁺ ; N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl4-methylpentanoyl)

-L-leucine-W- (4-aminoεulfonylphenyl) carboxamide, Η NMR (300 MHz, MeOH) δ 0.76 (d, J=6.5, 3H) , 0.81 (d, J=6.5, 3H) ,

0.85-1.1 (m, 7H) , 1.2-2.1 (m, 7H) , 2.92-2.95 (m, 1H) , 3.45-3.70 (m,

2H) , 4.35-4.45 (m, 1H) , 7.28 (d, J=8.7, 1H) , 7.45 (t, J=8.7, 1H) ,

7.68 (t, J=8.7, 1H) , 7.7-7.8 (m, 3H) , 7.87 (d, J=8.7, 1H) , 7.95-8.1

(m, 3H) ; N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-4-methylpentanoy l)

-L-leucine-W- (4-methoxycarbonylmethylphenyl) carboxamide,

MS(FAB) 628 (MH) ⁺ .

C. In a similar manner, the following compounds of formula (la) are prepared: N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl-5-phenylpentanoyl )

-L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl- -phenylbutanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-3-phenylpropanoy l) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide;

N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-3-cyclohexyl- propanoyl) -L-leucine-W- (4-methoxycarbonylphenyl) carboxamide; N- (2- ( (hydroxy) (quinolin-2-ylthiomethyl)phosphinoylmethyl)pentanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2- (hydroxy) (naphth-1-ylthiomethyl)phosphinoylmethyl-5-phenylpentanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2- (hydroxy) (naphth-l-ylthiomethyl)phoεphinoylmethyl-4-phenylbutanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2- (hydroxy) (naphth-l-ylthiomethyl)phoεphinoylmethyl-3-phenylpropanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide;

N- (2- (hydroxy) (naphth-1-ylthiomethyl)phosphinoylmethyl-3-cyclohexyl- propanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2- ( (hydroxy) (naphth-1-ylthiomethyl)phosphinoylmethylJpentanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2- (hydroxy) (naphth-2-ylthiomethyl)phosphinoylmethyl-5-phenylpentanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2- (hydroxy) (naphth-2-ylthiomethyl)phosphinoylmethyl-4-phenylbutanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2- (hydroxy) (naphth-2-ylthiomethyl)phosphinoylmethyl-3-phenylpropanoyl) -L-leucine-W-(4-methoxycarbonylpheny1)carboxamide;

N- (2- (hydroxy) (naphth-2-ylthiomethyl)phosphinoylmethyl-3-cyclohexyl- propanoyl) -L-leuc."ine-W- (4-methoxycarbonylphenyl)carboxamide,-

N- (2- ( (hydroxy) (naphth-2-ylthiomethyl)phosphinoylmethyl)pentanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl) carboxamide; N- (2- (hydroxy) (phenylthiomethyl)phosphinoylmethyl-5-phenylpentanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl) carboxamide; N- (2- (hydroxy) (phenylthiomethyl)phosphinoylmethyl-4-phenylbutanoyl) -L-leucine-W- (4-methoxycarbonylphenyl) carboxamide;

N- (2- (hydroxy) (phenylthiomethyl)phosphinoylmethyl-3-phenylpropanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl) carboxamide,- N- (2- (hydroxy) (phenylthiomethyl)phoεphinoylmethyl-3-cyclohexylpropanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; and N- (2- ( (hydroxy) (phenylthiomethyl)phoεphinoylmethyl)pentanoyl)

-L-leucine-W- (4-methoxycarbonylphenyl) carboxamide.

D. A εolution of N- (2- (hydroxy) (quinolin-2-ylthiomethyl) - phoεphinoylmethyl-4-methylpentanoyl) -L-tryptophan-W- (4-methoxycarbonyl- phenyl) carboxamide in THF (2 mL) and IM NaOH (1 mL) waε εtirred for 24 hours at 25°C. The organic solvents were evaporated, and the residue disεolved in ethyl acetate/H ₂ 0. The aqueouε phaεe waε acidified with IM HCl and the separated aqueous phase was extracted twice with ethyl acetate. The combined organic layers were washed with brine, dried (MgS0 ₄ ) and concentrated to 27 mg of N- (2- (hydroxy) (quinolin-2-ylthiomethyl) - phoεphinoylmethyl- -methylpentanoyl) -L-tryptophan-W- (4-carboxyphenyl) - carboxamide aε a yellow powder.

E. In a similar manner, but starting with N- (2- (hydroxy) (quinolin- 2-ylthiomethyl)phosphinoylmethyl-4-methylpentanoyl) -L-leucine-W- (4- methoxycarbonylphenyl) carboxamide (30 mg, 0.048 mmol), there was obtained 10 mg of N- (2- (hydroxy) (quinolin-2-ylthiomethyl)phoεphinoylmethyl-4- methylpentanoyl) -L-leucine-W- (4-carboxyphenyl) carboxamide as a εemisolid after trituration with ethyl acetate; ^l H NMR ¹ (300 MHZ, MeOH) 0.81-1.02 (m, 12H) , 1.1-2.3 (m, 10H) , 2.82-3.00 (m, 1H) , 3.49, 3.56 (2s,2H), 3.5-3.8 (m,2H), 4.45-4.55 (m,lH), 7.09 (d, J=8.2, 1H) , 7.19 (d, J=8.2,1H), 7.45 (t, J=8.2, 1H) 7.45-7.6 (m, 3H) , 7.65-7.80 (m, 1H) , 7.82-7.98 (m, 2H) , 8.10-8.20 (m, 1H) .

Example 11 Compoundε of formula (Fa)

A. To 4-methylpentanoic acid (25 g, 0.215 mmol) in a 25°C water bath, thionyl chloride (20.4 mL, 1.3 g) waε εlowly added. The mixture was heated at 50°C under argon for 3 hours (until the evolution of gas had stopped) . The crude reaction mixture was distilled at atmospheric pressure to give 4-methylpentanoyl chloride (25.3 g, 87.3%), b.p. 143°C.

B. In a similar manner, but replacing 4-methylpentanoic acid with 5-phenylpentanoic acid (5 g) , 5-phenylpentanoyl chloride was prepared (4.4 g) , aε a colorleεs liquid, b.p. 91°-93°C.

Example 12 Compounds of formula (Fb)

A. To a suspension of 60% NaH (836 mg, 1.5 eq.) in toluene (200 mL) at room temperature under argon was added L- (+) -2,10-camphor sultam (3.0 g, 3.9 mmol) portion-wise. The mixture was stirred vigorously at room temperature for one hour. Then 4-methylpentanoyl chloride waε carefully added dropwise to the solution at 0°C. After stirring the reaction at room temperature for 3 hours, the reaction was uenched with 10 mL of water, and 70 mL of ether was added. The reaction mixture was firεt waεhed with 0.5N HCl (2x50 mL) , then 5% "K-CO _j (3x50 mL) and finally with brine (1x50 mL) .

The organic layer waε dried over MgS0 ₄ , filtered and evaporated to dryneεs. Purification by column chromatography (1:6 ethyl acetate/petroleum ether as eluant) gave W4-methylpentanoyl-L- (+) -2,10-camphor εultam (3.39 g, 78%) .

B. In a similar manner, but replacing 4-methylpentanoyl chloride with the appropriate chloride, the following compounds of formula (Fb) were prepared: i\T-3-phenylpropanoyl-L- (+) -2,10-camphor εultam, MS: 347 (M ^*1* ) ; N-5-phenylpentanoyl-L- (+) -2,10-camphor sultam, MS: 375 M ⁺ ; Wpentanoyl-L- (+) -2,10-camphor sultam, MS: 300 (M+H) ⁺ .

Example 13 Compounds of formula (Fc)

A. To a solution of W4-methylpentanoyl-L- (+) -2,10-camphor sultam (3.39 g, 10.8 mmol) in 75 mL of dry THF at -78°C under argon was added NaN(TMS) ₂ (1.0 M in THF, 11.34 mL, 1.05 eq.) dropwise over five minutes. After stirring at -78°C for 1 hour, hexamethylphoεphoramide (5 mL) waε added to the mixture, followed by t-butylbromoacetate (5.2 ml, 3 eq) , then 400 mg of tetra n-butyl ammonium iodide was added in one portion. The reεulting εolution waε kept at -78°C under argon overnight. The next morning, the reaction was quenched with water (100 mL) and then extracted with ether (3x100 mL) . The combined ether layers were washed with brine, dried over NajSO,,, filtered and concentrated. Purification by column chromatography (5:95 ethyl acetate/petroleum ether to 10:90 ethyl acetate/petroleum ether as eluant) gave N- (4-methyl-2- -butoxycarbonyl- methyl)pentanoyl-L- (+) -2,10-camphor sultam (4 g, 86.5%) .

B. In a similar manner, but replacing W-4-methylpentanoyl-L- (+) - 2, 10-camphor sultam with the appropriate compound of formula (Fb) , the following compounds of formula (Fc) were prepared:

N- (3-phenyl-2- -butoxycarbonylmethyl)propanoyl-L- (+) -2,10-camphor sultam, MS: 461 (M ⁺ ) ;

N- (5-phenyl-2- -butoxycarbonylmethyl)pentanoyl-L- (+) -2,10-camphor sultam,

MS: 490.1 (M+H) ⁺ ; N- (2- -butoxycarbonylmethyl)pentanoyl-L- (+) -2,10-camphor sultam,

MS: 414 (M+H) ⁺ .

Example 14 Compounds of formula (F)

A. To a stirred solution of N- (4-methyl-2- -butoxycarbonylmethyl) pentanoyl-L- (+) -2,10-camphor sultam (5.45 g, 12.7 mmol) in 50% aqueous THF (150 mL) at 0°C under argon was added LiOHH ₂ 0 crystals (2.14 g, 4 eq.) followed by 30% H ₂ 0 ₂ (11.5 mL) . The ice-bath was removed and the resulting emulsion waε stirred for 3 hours before it turned clear. Most of the THF was removed under reduced pressure at 35°C. CH ₂ C1 ₂ (150 mL) was added and then 4N HCl with stirring to pH=2. After adding NaCl, the aqueous layer was extracted with CH ₂ C1 ₂ (3x150 mL) . The CH ₂ C1 ₂ was removed under reduced pressure at 35°C. The residue was taken up in ethyl acetate (150 mL) . This solution was then extracted with 5% K-C0 ₃ (3x50 mL) and the combined extracts were washed with ether (50 mL) . CH-C1 ₂ was added to the aqueous layer and then NaCl with stirring. The aqueous layer was extracted with CH ₂ C1 ₂ (3x70 mL) and the combined extracts were dried over Na ₂ S0 ₄ , filtered and concentrated to give (2_.) -4-methyl-2- -butoxycarbonylmethylpentanoic acid as a colorlesε oil (2.95 g, quantitative yield) .

B. In a εimilar manner, but replacing N- (4-methyl-2-t-butoxy- carbonylmethyl)pentanoyl-L- (+) -2,10-camphor εultam with the appropriate compound of formula (Fc) , the following compoundε of formula (F) were prepared:

(2R) -3-phenyl-2-t-butoxycarbonylmethyl-propanoic acid, MS: 265 (M+H) ⁺ ; (2R) -5-phenyl-2-t-butoxycarbonylmethyl-pentanoic acid, MS: 293.1 (M+H) ⁺ ; (21?) -2- -butoxycarbonylmethyl-pentanoic acid, (colorless oil, 1.09 g) . C. (2J.) -3-Phenyl-2- -butoxycarbonylmethyl-propanoic acid (55 mg) was taken up in glacial acetic acid (20 mL) and Pt0 ₂ (25 mg) was added in acetic acid. The beaker was placed in a Parr bomb, it was evacuated and charged with 100 psi of Hj. After εtirring for 3 dayε, the mixture waε εuction filtered through a 1 cm bed of celite. The filtrate waε then concentrated to a yellow oil, (22.) -3-cyclohexyl-2- -butoxycarbonylmethyl- propanoic acid (56 mg) , MS: 269.5 (M-H)\

Example 15 Compoundε of formula (lb) A. To a εolution of 4-methyl-2-t-butoxycarbonylmethylpentanoic acid (0.28 g, 1.2 mmol) in DMF (5 mL) containing HOBT (0.22 g, 1.8 mmol) was added EDCI (0.31 g, 1.8 mmol) . The mixture was stirred at 0°C for 1 hour and waε then treated with L-cyclohexylglycine-W- (4-methoxycarbonyl¬ phenyl)carboxamide (1.2 mmol) and DMAP (27 mg, 0.24 mmol) . Stirring was continued for 24 hours at 25°C and then the DMF was evaporated. The residue waε dissolved in CH ₂ C1 ₂ (20 mL) and the solution was washed with IM HCl (10 mL) , saturated NaHC0 ₃ (10 mL) , brine (10 mL) and dried over Na ₂ S0 ₄ . Concentration in vacuo afforded an oil which was purified by flash chromatography on Si0 ₂ using 20% ethyl acetate/hexenes aε eluent.

There was obtained 0.22 g (22%) of N- (4-methyl-2-t-butoxycarbonyl- methylpentanoyl) -L-cyclohexylglycine-W- (4-methoxycarbonylphenyl) carboxamide as a solid, MS(FAB) 503 (MH) ⁺ .

B. In a similar manner, the following compounds were prepared: N- (4-methyl-2-t-butoxycarbonylmethylpentanoyl) -L-pyridin-

3-ylalanine-W- (4-methoxycarbonylphenyl) carboxamide; N- (4-methyl-2- -butoxycarbonylmethylpentanoyl) -L-0-benzyl- threonine-W- (4-methoxycarbonylphenyl) carboxamide; N- (4-methyl-2-t-butoxycarbonylmethylpentanoyl) -L-isoleucine- N' - (4-methoxycarbonylphenyl)carboxamide;

N- (4-methyl-2- -butoxycarbonylmethylpentanoyl) -L-leucine-

W- (4-methoxycarbonylphenyl)carboxamide; N- (4-methyl-2- -butoxycarbonylmethylpentanoyl) -L- -leucine-

W- (4-methoxycarbonylphenyl)carboxamide; N- (4-methyl-2- -butoxycarbonylmethylpentanoyl) -L-leucine-

W- (4-cyanopheny1)carboxamide; N- (4-methyl-2- -butoxycarbonylmethylpentanoyl) -L-leucine-

N' - (4- (W '- (3-dimethylaminopropyl)carbamoyl)phenyl) - carboxamide; N- (4-methyl-2- -butoxycarbonylmethylpentanoyl) -L-leucine-

W- (4- (W '- (2-dimethylaminoethyl)carbamoyl)phenyl) - carboxamide,- N- (4-methyl-2-t-butoxycarbonylmethylpentanoyl) -L-leucine-

W- (4-aminoεulfonylphenyl)carboxamide; N- (4-methyl-2- -butoxycarbonylmethylpentanoyl) -L-leucine-

W- (4-methylaminoεulfonylphenyl)carboxamide; N- (2-t-butoxycarbonylmethylpentanoyl) -L-leucine-

W- (4-methoxycarbonylphenyl)carboxamide; N- (3-phenyl-2-t-butoxycarbonylmethylpropanoyl) -L-leucine- W- (4-methoxycarbonylpheny1)carboxamide;

N- (3-cyclohexyl-2- -butoxycarbonylmethylpropanoyl) -L-leucine-

W- (4-methoxycarbonylphenyl)carboxamide; N- (4-phenyl-2-t-butoxycarbonylmethylbutanoyl) -L-leucine-

W- (4-methoxycarbonylphenyl)carboxamide; and N- (5-phenyl-2- -butoxycarbonylmethylpentanoyl) -L-leucine-

W- (4-methoxycarbonylphenyl)carboxamide.

Example 16

Compounds of formula (Ic) A. To a cold (0°C) εolution of N- (4-methyl-2- -butoxycarbonyl- methylpentanoyl) -L-cyclohexylglycine-W- (4-methoxycarbonylphenyl) - carboxamide (70 mg, 0.14 mmol) in CH ₂ C1 ₂ (2 mL) waε added TFA (0.5 mL) . After εtirring for 5 hours at 25°C, the solution waε concentrated in vacuo

and the product was purified by reverse phase HPLC using a gradient of acetonitrile and 50 mM NH ₄ OAc buffer to provide 44 mg (71%) of W (4-methyl- 2-carboxymethylpentanoyl) -L-cyclohexylglycine-W- (4-methoxycarbonylphenyl) - carboxamide as a white solid, MS (FAB) 445 (M-H) ^' . B. In a similar manner, the following compoundε were prepared:

N- (4-methyl-2-carboxymethylpentanoyl) -L-isoleucine-W- (4-methoxycarbonyl¬ phenyl)carboxamide, MS(FAB) 419 (M-H) ^* ; N- (4-methyl-2-carboxymethylpentanoyl) -L-leucine-W- (4-methoxycarbonyl¬ phenyl)carboxamide, MS(FAB) 419 (M-H) ^" ; N- (4-methyl-2-carboxymethylpentanoyl) -L-t-leucine-W- (4-methoxycarbonyl¬ phenyl)carboxamide; N- (4-methyl-2-carboxymethylpentanoyl) -L-leucine-W- (4-cyano- phenyl)carboxamide,

Η NMR (300 MHz, MeOH) δ 0.84-0.99 (m, 12H) , 1.15-1.82 (m, 6H) , 2.36- 2.41 ( , 1H) , 2.52-2.65 (m, 1H) , 2.8-2.95 (m, 1H) , 4.49-4.54 (m, 1H) ,

7.4-7.9 (m, 4H) ; N- (4-methyl-2-carboxymethylpentanoyl) -L-leucine-W- (4-aminosulfonyl- phenyl) carboxamide, Η NMR (300 MHZ, MeOH) δ 0.85-1.00 (m, 12H) , l.l- 1.3 (m, 2H) , 1.52-1.85 (m, 4H) , 2.31-2.95 (m, 3H) , 4.49-4.55 (m, 1H) , 7.75- 7.91 (m, 4H) ;

N- (4-methyl-2-carboxymethylpentanoyl) -L-leucine-W- (4-methylaminosulfonyl- phenyl)carboxamide, MS(FAB) 459 (M-H) ^" ; N- (2-carboxymethylpentanoyl) -L-leucine-W- (4-methoxycarbonyl¬ phenyl)carboxamide, MS (FAB) 405 (M-H) ^" ; N- (3-phenyl-2-carboxymethylpropanoyl) -L-leucine-W- (4-methoxycarbonyl¬ phenyl) carboxamide, MS(FAB) 455 (M+H) ⁺ ; N- (3-cyclohexyl-2-carboxymethylpropanoyl) -L-leucine-W- (4-methoxycarbonyl¬ phenyl)carboxamide, MS(FAB) 459 (M-H)"; N- (4-phenyl-2-carboxymethylbutanoyl) -L-leucine-W- (4-methoxycarbonyl- phenyl) carboxamide, MS(FAB) 467 (M-H)";

N- (4-phenyl-2-carboxymethylbutanoyl) -L-cyclohexylglycine-W- (4-methoxy¬ carbonylphenyl)carboxamide; N- (4-phenyl-2-carboxymethylbutanoyl) -L- -leucine-W- (4-methoxy¬ carbonylphenyl)carboxamide; N- (5-phenyl-2-carboxymethylpentanoyl) -L-leucine-W- (4-methoxy¬ carbonylphenyl) carboxamide, MS (FAB) 481 (M-H) ^" ; and N- (4-methyl-2-carboxymethylpentanoyl) -L-O-benzylthreonine-W- (4-methoxy¬ carbonylphenyl)carboxamide, MS(FAB) 497 (M-H)".

C. In a similar manner, but triturating the crude product with ether and then decanting the ether to yield the following compounds as TFA salts: N- (4-methyl-2-carboxymethylpentanoyl) -L-pyridin-3-ylalanine-

W- (4-methoxycarbonylphenyl)carboxamide, MS(FAB) 456 (M+H) ⁺ ;

N- ( -methyl-2-carboxymethylpentanoyl) -L-leucine-W- (4- (W '- (3-dimethyl- aminopropyl) carbamoyl)phenyl)carboxamide, MS(FAB) 491 (M+H) ⁺ ; and N- (4-methyl-2-carboxymethylpentanoyl) -L-leucine-W- (4- (W '- (2-dimethyl- aminoethyl)carbamoyl)phenyl) carboxamide, MS(FAB) 491 (M+H) ⁺ . D. A mixture of N- (4-methyl-2- -butoxycarbonylmethyl-pentanoyl) -L-

O-benzylthreonine-W- (4-methoxycarbonylphenyl) -carboxamide (60 mg) and Pd/C in ethyl acetate/THF (1:1, 25 mL) was hydrogenated overnight at 1 atm preεsure. Filtration through Celite, concentration of the filtrate, and trituration of the residue with ether/hexeneε produced N- (4-methyl-2- - butoxycarbonylmethyl-pentanoyl) -L-threonine-W- (4-methoxycarbonylphenyl) - carboxamide, MS (FAB) 407 (M-H)".

Example 17

Compounds of formula (Id) A. A solution of N- (4-methyl-2-carboxymethylpentanoyl) -L-leucine-

W- (4-methoxycarbonylphenyl)carboxamide (0.28 g, 0.66 mmol) and HOBT (0.12 g) in dry DMF (20 mL) was cooled to 0°C and treated with EDCI (0.32 g) . After stirring 0.5 hours at 0°C, O-benzylhydroxylamine (0.30 mL) waε added and the reaction was allowed to warm to 25°C overnight. The DMF was removed in vacuo and the residue was taken up in CH ₂ C1 ₂ and washed with 5% HCl/5% NaHC0 ₃ and brine and the solution was dried over Na-S0 ₄ . After concentration, the product was purified by flash chromatography (Si0 ₂ , R _f =0.6, 10% MeOH/CH ₂ Cl ₂ ) . The product containing fractions were further purified by trituration with CH ₂ C1 ₂ to give N- (4-methyl-2- (W '-benzyloxy- carbamoyl)methylpentanoyl) -L-leucine-W- (4-methoxycarbonylphenyl) - carboxamide as a solid, mp 198-199°C.

B. In a similar manner, the following compoundε were prepared: N- (2- (W '-benzyloxycarbamoyl)methylpentanoyl) -

L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (4-phenyl-2- (W '-benzyloxycarbamoyDmethylbutanoyl) -

L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; and N- (4-methyl-2- (W '-benzyloxycarbamoyl)methylpentanoyl) -

L-tryptophan-W- (4-methoxycarbonylphenyl)carboxamide.

C. N- (4-Methyl-2- (W '-benzyloxycarbamoyl)methylpentanoyl) - L-leucine-W- (4-methoxycarbonylphenyl) -carboxamide (210 mg) was hydrolyzed with IM NaOH (1.4 mL) at 50-60°C for 2 hour in THF (20 mL) and MeOH (5 mL) . The organic solvents were evaporated and the residue was taken up in 10 mL H ₂ 0 and washed with ether (2x10 mL) . The aqueous phase waε acidified to pH 2 with 10% HCl and extracted with ethyl acetate (3x10 mL) . The combined extractε were washed with brine, dried over Na ₂ S0 ₄ , and concentrated to afford N- (4-methyl-2- (W '-benzyloxycarbamoyl)methylpentanoyl) -L-leucine-W- (4-carboxypheny1)carboxamide (110 mg) .

Example 18

Compounds of formula (Ie)

A. To a solution of N- (4-phenyl-2- ( '-benzyloxycarbamoyl) - methylbutanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide (25 mg) in 20 mL MeOH and 10 mL THF was added 10% Pd/C (20 mg) . The εuspenεion was hydrogenated for 1 hour and then suction filtered through Celite. Concentration afforded the product which waε purified on εilica (2.5% MeOH/CH ₂ Cl ₂ ) to give 8 mg of N- (4-phenyl-2- (W '-hydroxycarbamoyl) - methylbutanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide, MS(FAB) 482 (M-H) ^" .

B. In a similar manner, the following compounds were prepared: N- (4-methyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) -L-leucine-W-

(4-carboxyphenyl)carboxamide; N- (4-methyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide, MS(FAB) 436 (M+H) ⁺ ; Compound 2

N- (2- (W '-hydroxycarbamoyl)methylpentanoyl) -L-leucine-W- (4- methoxycarbonylphenyl)carboxamide, MS(FAB) 420 (M-H)',- N- (4-phenyl-2- (W '-hydroxycarbamoyl)methylbutanoyl) -L- -leucine-W- (4-methoxycarbonylphenyl)carboxamide,- N- (4-phenyl-2- (W '-hydroxycarbamoyl)methylbutanoyl) -

L-cyclohexylglycine-W- (4-methoxycarbonylphenyl)carboxamide; N- (4-phenyl-2- (W '-hydroxycarbamoyl) ethylbutanoyl) -

L-leucine-W- (4-methoxycarbonylphenyl) carboxamide; N- (4-methyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) - L- -leucine-W- (4-methoxycarbonylphenyl)carboxamide;

N- (4-methyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) - -tryptophan- W- (4-methoxycarbonylphenyl) carboxamide, MS(FAB) 507 (M-H)"; Compound 3 (2R) ; Compound 4 (2S) ; and N- (4-phenyl-2- (W '-hydroxycarbamoyl) ethylbutanoyl) - L-leucine-W- (4-methoxycarbonylphenyl)carboxamide.

C. In a similar manner, the following compoundε are prepared: N- (3-phenyl-2- (W '-hydroxycarbamoyl) ethylpropanoyl) -

L-leucine-W- ( -methoxycarbonylphenyl)carboxamide; N- (5-phenyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) - L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; and

N- (3-cyclohexyl-2- (W '-hydroxycarbamoyl)methylpropanoyl) - L-leucine-W- (4-methoxycarbonylphenyl)carboxamide.

Example 19 Compounds of formula (Gb)

A. To a cold (0°C) solution of diethyl isobutylmalonate (21.6 g, 0.1 mol) in 150 mL of ethanol was added a solution of KOH (5.89 g, 0.1 mol) εlowly over 30 minuteε. The clear εolution waε stirred at 25°C for 60

hourε. The ethanol was removed under reduced presεure and the solid residue waε diεsolved in 50 mL of Α-O . The aqueous solution waε acidified to pH 2 with 4M HCl and extracted with ether (2x50 mL) . The combined extracts were dried over MgS0 ₄ and evaporated to provide 19.0 g (100%) of ethyl isobutylmalonate as a colorless oil.

B. In a similar manner, the following compoundε of formula (Gb) are prepared: ethyl tert-butylmalonate; ethyl propylmalonate; ethyl benzylmalonate; and ethyl cyclohexymethylmalonate.

Example 20

Compounds of formulae (Gc) and (Gd) A. To neat ethyl isobutylmalonate (25 g, 0.13 mol) at 0°C was εlowly added ice cold diethylamine (15.1 mL, 0.15 mol) . After εtirring for 15 minuteε, formalin (11.1 mL of 37% aqueous formaldehyde) waε added dropwise and the mixture was allowed to stir at 25°C for 3 days. The reaction was treated with a solution of 20 g of K_C0 ₃ in 40 mL of HjO and extracted with ether (2 x 100 mL) . The combined ether layers were washed with brine, dried over MgS0 ₄ , and evaporated at 20°C on a rotary evaporator. The crude product ethyl 4-methyl-2-methylenepentanoate (containing some ether) was disεolved in 250 mL of absolute ethanol and treated with acetonitrile (250 mL) , IM LiOH (9.7 g in 250 mL of Α_0, 0.23 mol) . After stirring overnight, the organic solvents were evaporated and the aqueous reεidue waε extracted with ethyl acetate (2x150 mL) . The combined extractε were waεhed with brine, dried (MgS0 ₄ ) , and evaporated to afford 10.5 g of 4-methyl-2-methylenepentanoic acid aε a colorleεε oil. B. In a similar manner, the following compounds of formula (Gd) are prepared:

4-phenyl-2-methylenebutanoic acid; 3-cyclohexyl-2-methylenepropanoic acid; 5-phenyl-2-methylenepentanoic acid; 2-methylenepentanoic acid; and 3,3-dimethyl-2-methylenebutanoic acid.

Example 21 Compounds of formula (G) A. A mixture of 4-methyl-2-methylenepentanoic acid (5.0 g) and thioacetic acid (25 mL) was heated at 95°C under argon for 3 days. The excess thioacetic acid was evaporated and the residual oil was disεolved in ethyl acetate (40 mL) and extracted with saturated NaHC0 ₃ (3x40 mL) . The combined NaHC0 ₃ extractε were combined and acidified at 0°C to pH 2 with IM HCl. The aqueouε layer waε extracted with CH-C1 ₂ (3x40 mL) , the combined organic phaεeε were dried (MgS0 ₄ ) , and finally evaporated to give 3.0 g of

4-methyl-2-acetylthiomethylpentanoic acid; Η NMR (80 MHz, CDCL ₃ ) δ 0.95 (d, J=8.0, 6H) , 1.20-1.90 (m, 4H) , 2.35 (s, 3H) , 2.50-3.20 (m, 3H) , 6.7 (br ε, 1H) .

Example 22

Compounds of formula (If)

A. To a εolution of 4-methyl-2-acetylthiomethylpentanoic acid (204 mg, 1.0 mmol) in dry DMF (15 mL) containing HOBT (92 mg, 0.6 mmol) and L- leucine-W- (4-methoxycarbonylphenyl)carboxamide (0.6 mmol) waε added EDCI (345 mg, 1.8 mmol) . The solution was stirred overnight at 25°C and then the DMF was removed in vacuo. The residue was disεolved in ethyl acetate (35 mL) and washed with IM HCl, IM NaOH, and brine. Drying over MgS0 ₄ and evaporation afforded a semiεolid which was flash chromatographed on silica gel (ethyl acetate l:petroleum ether 2) to give N- (4-methyl-2-acetylthio- methylpentanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide (190 mg) aε a white solid.

B. In a similar manner, the following compounds of formula (If) are prepared:

N- (5-phenyl-2-acetylthiomethylpentanoyl) -L-leucine- W- (4-methoxycarbonylphenyl)carboxamide;

N- (4-phenyl-2-acetylthiomethylbutanoyl) -L-leucine-W- (4- methoxycarbonylphenyl) carboxamide,- N- (3-phenyl-2-acetylthiomethylpropanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (3-cyclohexyl-2-acetylthiomethylpropanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide; N- (2-acetylthiomethylpentanoyl) -L-leucine-W- (4- methoxycarbonylphenyl)carboxamide,- N- (5-phenyl-2-acetylthiomethylpentanoyl) -L-leucine- W- ( -aminocarbonylpheny1)carboxamide;

N- (4-phenyl-2-acetylthiomethylbutanoyl) -L-leucine-W-

(4-carboxyphenyl)carboxamide; N- (3-phenyl-2-acetylthiomethylpropanoyl) -L-leucine-W- (4-methylεulfonylphenyl)carboxamide; N- (3-cyclohexyl-2-acetylthiomethylpropanoyl) -L-leucine-W- (4-carbamoylphenyl)carboxamide; N- (2-acetylthiomethylpentanoyl) -L-leucine-W-

(4-cyanophenyl) carboxamide; N- (5-phenyl-2-acetylthiomethylpentanoyl) -L-tryptophan- W- (4-methoxycarbonylphenyl)carboxamide;

N- (4-phenyl-2-acetylthiomethylbutanoyl) -L-tryptophan-W- (4- methoxycarbonylphenyl)carboxamide; N- (3-phenyl-2-acetylthiomethylpropanoyl) -L-tryptophan-W-

(4-methoxycarbonylphenyl) carboxamide,- N- (3-cyclohexyl-2-acetylthiomethylpropanoyl) -L-tryptophan-W-

(4-methoxycarbonylphenyl)carboxamide; and N- (2-acetylthiomethylpentanoyl) -L-tryptophan-W- (4- methoxycarbonylphenyl)carboxamide.

Example 23

Compounds of formula (Ig)

A. To a solution of N- (4-methyl-2-acetylthiomethylpentanoyl) -L- leucine-W- (4-methoxycarbonylphenyl) carboxamide (85 mg, 0.19 mmol) in MeOH

(8 mL) at 0°C was added concentrated HN ₄ OH (0.4 mL) . After εtirring at 0°C for 5 hours, the methanol waε evaporated and ether (30 mL) was added. The ether solution was washed with 0.5 M HCl, brine, and was dried over MgS0 ₄ . Concentration afforded N- (4-me hyl-2-mercaptomethylpentanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide in quantitative yield as a white foam, MS(FAB) 407 (M-H)".

B. In a similar manner, the following compounds of formula (Ig) are prepared:

N- (5-phenyl-2-mercaptomethylpentanoyl) -L-leucine-W- (4-methoxycarbonylphenyl)carboxamide,-

N- (4-phenyl-2-mercaptomethylbutanoyl) -L-leucine-W-

(4-methoxycarbonylphenyl)carboxamide; N- (3-phenyl-2-mercaptomethylpropanoyl) -L-leucine-W-

(4-methoxycarbonylphenyl)carboxamide,- N- (3-cyclohexyl-2-mercaptomethylpropanoyl) -L-leucine-W-

(4-methoxycarbonylphenyl)carboxamide; N- (2-mercaptomethylpentanoyl) -L-leucine-W-

(4-methoxycarbonylphenyl)carboxamide; N- (5-phenyl-2-mercaptomethylpentanoyl) -L-leucine-W- (4-aminocarbonylphenyl)carboxamide;

N- (4-phenyl-2-mercaptomethylbutanoyl) -L-leucine-W-

(4-carboxyphenyl)carboxamide; N- (3-phenyl-2-mercaptomethylpropanoyl) -L-leucine-W-

(4-methylsulfonylphenyl)carboxamide; N- (3-cyclohexyl-2-mercaptomethylpropanoyl) -L-leucine-W-

(4-carbamoylphenyl)carboxamide; N- (2-mercaptomethylpentanoyl) -L-leucine-W-

(4-cyanophenyl)carboxamide,- N- (5-phenyl-2-mercaptomethylpentanoyl) -L-tryptophan-W- (4-methoxycarbonylpheny1)carboxamide;

N- (4-phenyl-2-mer-aptomethylbutanoyl) -L-tryptophan-W-

(4-methoxycarbonylphenyl)carboxamide; N- (3-phenyl-2-mercaptomethylpropanoyl) -L-tryptophan-W-

(4-methoxycarbonylphenyl) carboxamide; N- (3-cyclohexyl-2-mercaptomethylpropanoyl) -L-tryptophan-W-

(4-methoxycarbonylphenyl) carboxamide; and N- (2-mercaptomethylpentanoyl) -L-tryptophan-W- (4-methoxycarbonylpheny1) carboxamide.

Example 24 This example illustrates the preparation of representative pharmaceutical compositionε for oral adminiεtration containing a compound of formula (I), or a pharmaceutically acceptable salt thereof, e . g. , N- (4- methyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) -L-leucine-W- (4- methoxycarbonylphenyl) carboxamide:

A. Ingredients % wt. /wt.

Compound of formula (I) 20.0% Lactose 79.5%

Magnesium stearate 0.5%

The above ingredients are mixed and dispensed into hard-shell gelatin capsules containing 100 mg each, one capsule would approximate a total daily doεage. B. Ingredients % wt. /wt.

Compound of formula (I) 20.0%

Magneεium stearate 0.9%

Starch 8.6%

Lactose 69.6% PVP (polyvinylpyrrolidine) 0.9%

The above ingredients with the exception of the magnesium stearate are combined and granulated uεing water as a granulating liquid. The formulation is then dried, mixed with the magnesium stearate and formed into tablets with an appropriate tableting machine. C. Ingredients

Compound of formula (I) 0.1 g

Propylene glycol 20.0 g

Polyethylene glycol 400 20.0 g

Polysorbate 80 1.0 g Water q.s. 100 mL

The compound of formula (I) is dissolved in propylene glycol, polyethylene glycol 400 and polyεorbate 80. A sufficient quantity of water iε then added with stirring to provide 100 mL of the solution which is filtered and bottled. D. Ingredients % wt. /wt.

Compound of formula (I) 20.0%

Peanut Oil 78.0%

Span 60 2.0%

The above ingredientε are melted, mixed and filled into soft elastic capsules.

Example 25 This example illustrates the preparation of a representative pharmaceutical formulation for parenteral adminiεtration containing a compound of formula (I) , or a pharmaceutically acceptable salt thereof, e . g. , N- (4-methyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) -L-tryptophan-W- (4-carboxyphenyl) carboxamide: Ingredients

Compound of formula (I) 0.02 g

Propylene glycol 20.0 g Polyethylene glycol 400 20.0 g

Polysorbate 80 1.0 g

0.9% Saline solution q.s. 100 mL

The compound of formula (I) is dissolved in propylene glycol, polyethylene glycol 400 and polysorbate 80. A sufficient quantity of 0.9% saline solution is then added with stirring to provide 100 mL of the I.V. solution which is filtered through a 0.2 μ membrane filter and packaged under sterile conditions.

Example 26 This example illustrates the preparation of a representative pharmaceutical composition in suppository form containing a compound of formula (I), or a pharmaceutically acceptable salt thereof, e . g. , W-(4- methyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) -L-leucine-W- (4- carboxyphenyl) carboxamide: Ingredients % wt. /wt.

Compound of formula (I) 1.0%

Polyethylene glycol 1000 74.5%

Polyethylene glycol 4000 24.5%

The ingredientε are melted together and mixed on a steam bath, and poured into molds containing 2.5 g total weight.

Example 27 This example illustrates the preparation of a representative pharmaceutical formulation for insufflation containing a compound of formula (I), or a pharmaceutically acceptable salt thereof, e . g. , N- (4- methyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) -L-cyclohexylglycine-W- (4- methoxycarbony1-phenyl) carboxamide:

Ingredients % wt. /wt.

Micronized compound of formula (I) 1.0% Micronized lactose 99.0%

The ingredients are milled, mixed, and packaged in an insufflator equipped with a dosing pump.

Example 28 Thiε example illustrates the preparation of a representative pharmaceutical formulation in nebulized form containing a compound of formula (I), or a pharmaceutically acceptable salt thereof, e .g. , W(4- methyl-2- (W '-hydroxycarbamoyl)methylpentanoyl) -L- -leucine-W- (4- methoxycarbonylphenyl)carboxamide:

Ingredients % wt./wt.

Compound of formula (I) 0.005%

Water 89.995% Ethanol 10.000%

The compound of formula (I) iε diεεolved in ethanol and blended with water. The formulation iε then packaged in a nebulizer equipped with a doεing pump.

Example 29

This example illustrates the preparation of a representative pharmaceutical formulation in aerosol form containing a compound of formula (I), or a pharmaceutically acceptable salt thereof, e.g. , W(4- methyl-2-mercaptomethylpentanoyl) -L-leucine-W- (4-methoxycarbonyl- phenyl)carboxamide:

Ingredients % wt. /wt.

Compound of formula (I) 0.10%

Propellant 11/12 98.90%

Oleic acid 1.00% The compound of formula (I) is disperεed in oleic acid and the propellantε. The resulting mixture iε then poured into an aerosol container fitted with a metering valve.

Example 30 In vitro assay

Matrilysin was purified from cloned mammalian cell culture by Blue- Sepharose and zinc-chelating sepharoεe column followed by faεt protein liquid chromatography over a MONO S column. The enzyme waε activated by incubation with 1 mmol APMA for 1 hr at 35-37°C. Compounds of formula (I) were dissolved in DMSO and added to a cuvette containing 0.4 μg matrilysin in 1 ml TC buffer (20mM Tris, 5mM CaCl ₂ , pH 7.5) (2% DMSO final concentration). The concentrations of the compounds of formula (I) were chosen εuch that there was at least one data point for every 20% change in activity. Enzyme and compounds were permitted to preincubate 3 min at 37°C. To initiate the reaction, N- (7- dimethylamino-4-m_thyl)coumarinyl ("DACM") (Sigma) and thiopeptide (Ac-Pro- Leu-Gly-S-"Leu"-Leu-Gly-OEt, Bachem Bioscience Inc.) were added to 20 μM each. The fluorescence increase was recorded with excitation and emission wavelengths of 395 and 485 nm, respectively. Each data point is the average of duplicate experiments. At least εix data points, expresεed as

change in fluorescence per minute versus compound concentration were analyzed using the ICso fit in the program, Enzfitter.

Compounds of formula (I) exhibited the ability to inhibit matrilysin when tested in this assay. IC ₅₀ (nM)

HFC PTJMP HNG STROM. Compound 2 8.4 k'=140fM 1.4

Example 31 In vitro asεay

This assay determines if the compounds of formula (I) inhibit the releaεe of ³⁵ S-labelled glycosaminoglycans (GAG's) from cartilage explantε. Small cartilage explants (3 mm diameter) were prepared from freshly sacrificed bovine knee joints and labeled with ³⁵ S0 ₄ . ³⁵ S-labelled glycosaminoglycans (GAG's) are released into the culture medium in response to the addition of rhIL-1-alpha, which induces the expresεion of chondrocyte matrix metalloproteaεes (MMP's), including stromelysin and collagenase. The percent inhibition of labeled GAG's waε corrected for spontaneous release in the absence of rhlL-1-alpha. Results for each group represent the mean + the S.E.M. for five explants.

Compounds of formula (I) , when tested in this assay, displayed the ability to inhibit the release of ³⁵ S-labelled GAG'ε from cartilage explantε.

EC _JO (molar) Compound 2 3.5x10 ^* *

Example 32

In vitro aεεay An in vitro fetal rat long bone model waε uεed to study the anti-bone reεorptive effect of the compounds of formula (I) . Bovine PTH waε uεed to induce bone resorption in vitro. The bone resorptive effects were expressed by the amounts of ⁵ Ca releaεed from the ⁴⁵ Ca pre-labelled fetal rat long bones into the culture medium. The inhibitory effect of the compounds of formula (I) against bovine PTH induced bone reεorption was expresεed aε mean percent inhibition ± εem. ⁵ Ca-prelabelled fetal rat long bones (from forearms) were dissected and cultured in Linbro dishes at 37°C overnight BGJb medium, supplemented with lmg/ml BSA. There were five pairs of bones in each group. The compounds of formula (I) were dissolved in ethanol first, then diluted to various concentrationε and added simultaneously with Bovine PTH (1-34) at lxlO-tø on Day 1. The ethanol concentrations in the compound solutions were lesε than 0.05% which did not interfere with the assay. The asεay was terminated on Day 6 with one media change on Day 3.

At the end of each medium change, the ⁵ Ca present in the culture

medium was counted. The remaining bones were digeεted with 0.1N HCl and the ⁴⁵ Ca presented in the bone digest was also counted. The reεults are expressed as % of the total ⁴⁵ Ca released from each pair of bones. Bovine PTH at lxlO-^ induces bone resorption to the maximum level which iε εet aε 100% and this concentration was used aε εtandard. The level of baεe line bone resorption in the presence of medium only was set aε 0%. All compound-treated groupε were compared with bovine PTH (1-34) at lxlO-'M. The concentration at which a compound inhibited bone reεorption by 50% waε defined as IC ,. The compounds of formula (la) exhibited the ability to inhibit bovine

PTH-induced bone resorption in this asεay.

IC ₅₀ (molar)

Compound 1 £5 10 ^* * Compound 2 2.7xl0 ^"7

Compound 3 δxlO ^-8

Compound 4 ≥SxlO ^-6

TOXICOLOGY

No serious toxicological effects were observed in the above described aεεayε.