Background of the invention Opioid antagonists have been indispensable as tools in opioid research. For example, the chief criterion for the classification of an agonist effect as being opioid receptor mediated is the ability of known opioid antagonists naloxone or naltrexone to reversibly antagonize this effect in a competitive fashion. The usefulness of naloxone and naltrexone for this purpose stems from the fact that they are universal opioid antagonists; that is, they are capable of antagonizing the agonist effects mediated by multiple opioid receptor types.

In addition to their uses as pharmacological tools, selective, non-peptide opioid antagonists have been described as having potential clinical applications in the treatment of a variety of disorders where endogenous opioids play a modulatory role. These include for instance disorders of food intake, shock, constipation, mental disorders, CNS injury, alcoholism, and immune function (P.S. Portoghese at al., J. Med. Chem., Vol. 34: 1757-1762, 1991).

Non-peptide, competitive, 6selective opioid antagonists have been found to have immunosuppressive potency and less toxicity than the presently used immunosuppressive compound cyclosporin (EP 456 833; EP 485 636; EP 614 898; K. Arakawa et al., Transplantation, Vol. 53: 951-953, 1992; K. Arakawa et al., Transplant Proc., Vol. 24: 696-697, 1992; K. Arakawa et al., Transplant Proc., Vol. 25: 738-740, 1993). Such immunosuppressive agents can be used after organ transplantation to suppress the rejection

of the foreign organ and also in the treatment of autoimmune diseases (e.g. rheumatoid arthritis).

In US 5 223 507 and US 5 225 417 the synthesis of 14-0-substituted indolomorphinans and benzofuranomorphinans have been disclosed. According to the process used for preparing the compounds claimed and disclosed in US 5 223 507, only a 3,14-dimethoxy substituted benzofuranomorphinan was prepared. According to the process used for preparing compounds claimed and disclosed in US 5 225 417, two 14-0-alkyl substituted benzofuranomorphinans have been prepared. According to the methods used for preparing the compounds of both the two mentioned prior art documents, the 3-hydroxy group was protected by a methyl group which is not easily removed without having a loss in yield.

According to the processes known from the prior art, the variations of the substituents at the oxygen in position 14 are very much limited when a 3-hydroxy group is supposed to be present in the molecule. It is for instance not possible to prepare compounds with a substituent at the oxygen in 14-position, as this position is labile to the conditions used for the cleavage of the 3-methoxy group.

Thus, the object of the present invention was to find a new process which would facilitate the preparation of 14-0-substituted indolomorphinans and benzofuranomorphinans.

The present patent application discloses a process whereby naloxone, naltrexone or oxymorphone is used as the starting material, whereby the 14-alkoxy group is introduced after the protection of the oxygen in 3-position with an easily removable protecting group, preferably benzyl, methoxymethyl, ethoxymethyl, trityl or silyl, thereby providing a process enabling the synthesis of compounds involving 14-0-substitution.

Outline of the invention The present invention is directed to a new process for the preparation of compounds of the general formula (I) wherein R1 represents allyl, cyclopropylmethyl or methyl; R2 represents C1-C6 alkoxy, C1-C6 alkenyloxy, C7-C16 arylalkyloxy wherein aryl is C6-C1o aryl and alkyloxy is C1-C6 alkyloxy, C7-C16 arylalkenyloxy wherein aryl is C6-C10 aryl and alkenyloxy is C1-C6 alkenyloxy, C1-C6 alkanoyloxy, C7-C16 arylalkanoyloxy wherein aryl is C6-C10 aryl and alkanoyloxy is C1-C6 alkanoyloxy; R3 represents hydroxy, C1-C6 alkoxy, C7-C16 arylalkyloxy wherein aryl is C6-C10 aryl and alkyloxy is C1-C6 alkyloxy, Cl-C6 alkenyloxy, C1-C6 alkanoyloxy, C7-C16 arylalkanoyloxy wherein the aryl is C6-C10 aryl and the alkanoyloxy is C1-C6 alkanoyloxy, C2-C1o alkyloxyalkoxy wherein alkyloxy is C1-C4 alkyloxy and alkoxy is C1-C6 alkoxy; and X represents 0, NH or NR4 wherein R4 is C1-C6 alkoxy, C1-C6 alkenyloxy, C7-C16 arylalkyloxy wherein aryl is C6-C10 aryl and alkyloxy is C1-C6 alkyloxy, C7-C16 arylalkenyloxy wherein the aryl is C6-C10 aryl and alkenyloxy is C1-C6 alkenyloxy, C1-C6 alkanoyloxy, C7-C16 arylalkanoyloxy wherein aryl is C6-C10 aryl and alkanoyoloxy is C1-C6 alkanoyloxy.

The process for the preparation of the compounds of the general formula (I) comprises the following steps: (i) Naloxone (II), naltrexone (III) or oxymorphone (IIIa) of the formula (ill): fl = allyl (111): R = cyclopropylmethyl (Illa): R = methyl is reacted with phenylhydrazine hydrochloride in the presence of an acid, preferably methanesulfonic acid, sulfuric acid or hydrochloric acid, giving naloxindole (NLI), naltrindole (NTI) or oxymorphindole (OMI), PS. Portoghese et al., J. Med. Chem. Vol. 31: 281-282, 1988, of the following formula: NLI: R= allyl, X= NH NTI: R = cyclopropylmethyl, X = NH OMI: R = methyl, X = NH or; naloxone (II), naltrexone(III) or oxymorphone is reacted with O-phenyl-hydroxyl amine hydrochloride in the presence of an acid, preferably methanesulfonic acid, sulfuric acid or hydrochloric acid, giving the benzofurane derivatives NLB, naltriben (NTB; P. S.

Portoghese et al., J. Med. Chem., Vol. 34: 1715-1720, 1991) or OMB (US 5 223 507) of the formula NLB: fl = allyl, X = 0 NTB: R = cyclopropylmethyl, X = 0 OMB: R = methyl, X = 0 (ii) the 3-hydroxy group is protected by alkylation with benzyl bromide, methoxymethyl bromide, ethoxymethyl bromide, trityl chloride or a silylating agent, preferably dimethyl isobutyl-silyl chloride, trimethylsilyl chloride, triethylsilyl chloride, t-butyldimethylsilyl chloride or tri-i-propylsilyl chloride, in a solvent, preferably N,N-dimethylformamide, dichloromethane or tetrahydrofurane, in the presence of a base which may not be a weak base, preferably potassium carbonate, potassium hydroxide, sodium hydride, sodium amide or diisopropyl ethylamine, giving a compound of the formula (IV) wherein R1 is allyl, cyclopropylmethyl or methyl; R2 is benzyl, methoxymethyl, ethoxymethyl, trityl or silyl, preferably dimethyl isobutyl silyl, trimethylsilyl, triethylsilyl, t-butyldimethylsilyl or tri-i-propylsilyl; and

X is NH, O, N-benzyl, N-methoxymethyl, N-ethoxymethyl, N-trityl or N-silyl, preferably dimethyl isobutyl silyl, trimethylsilyl, triethylsilyl, t-butyldimethylsilyl or tri-i-propylsilyl; (iii) the compound of the formula (IV) is treated with C1-C2 dialkyl sulfates, C1-C6 alkyl halides, C1-C6 alkenyl halides, C7-C16 aralkyl halides wherein the aryl is C6-C1o aryl and the alkyl is C1-C6 alkyl, C7-C16 arylalkenyl halides wherein the aryl is C6-C10 aryl and the alkenyl is C2-C6 alkenyl, C2-C6 alkanoyl halides, C7-C16 arylalkanoyl halides wherein the aryl is C6-C10 aryl and the alkanoyl is C2-C6 alkanoyl, in a solvent, preferably N,N- dimethyl formamide or tetrahydrofurane, using a strong base, preferably sodium hydride, potassium hydride or sodium amide, giving a compound of the formula (V) wherein R1 is allyl or cyclopropylmethyl; R2 is benzyl, methoxymethyl, ethoxymethyl, trityl or silyl, preferably dimethyl isobutyl silyl, trimethylsilyl, triethylsilyl, t-butyldimethylsilyl or tri-i-propylsilyl; and R3 is C1-C6 alkyl, C1-C6 alkenyl; C7-C16 arylalkyl wherein the aryl is C6-C10 aryl and the alkyl is C1-C6 alkyl; C7-C16 arylalkenyl wherein the aryl C6-C10 aryl and the alkenyl is C1- C6 alkenyl; C1-C6 alkanoyl, C7-C16 arylalkanoyl wherein the aryl is C6-C1o aryl and the alkyl is C1-C6 alkyl; X is as defined in the formula (IV) above; and

optionally the following step (iv) whereby (iv) the compound of the formula (V) wherein X is NH, O, N-benzyl, N-methoxymethyl, N- ethoxymethyl, N-trityl or silyl, preferably dimethyl isobutyl silyl, trimethylsilyl, triethylsilyl, t-butyldimethylsilyl or tri-i-propylsilyl; is hydrolized in diluted acids, preferably hydrochloric acid or sulfuric acid, optionally in the presence of a solvent, preferably an alcohol, and in particular methanol, ethanol or n- propanol, giving a compound of the formula (VI) wherein R1, and R3 are as defined above in formula (V), and X is NH, O or N-benzyl; and (v) the compound of the formula (VI) is alkylated or acylated, giving a compound of the formula (I).

Detailed description of the invention The invention will now be described in more detail by the following examples.

EXAMPLES Example 1 Synthesis of 1 7-(Cyclopropylmethyl)-6 ,7-dehydro-4,5epoxy- 14-hydroxy-3- (methoxymethoxy)-6,7-2',3'-benzo[b]furanomorphinan (compound 1).

Sodium hydride (426 mg, 17.7 mmol; obtained from 710 mg of sodium hydride dispersion in oil by washings with n-hexane) was added to a solution of naltriben methanesulfonate (2.0 g, 3.9 mmol) in 30 ml of anhydrous N,N-dimethyl formamide at 0° C. The resulting mixture was stirred at 0° C for 20 min and then at room temperature for another 60 min.

After cooling to 0° C, methoxymethyl bromide (653 pil, 8 mmol) was added and stirring was continued for 15 min at 0° C and then for additional 120 min at room temperature. Excess sodium hydride was destroyed by addition of methanol and H20. The resulting mixture was extracted with ethyl acetate (4 x 50 ml), the combined organic layers were washed with H2O (2 x 50 ml) and brine, dried over Na2SO4 and evaporated to give an oil which was crystallized from MeOH to yield 1.0 g (56%) of compound 1. M. p. 129-130° C.

1H-NMR (CDCl3): 5 7.45 (d, J = 8.3 Hz, 1 arom. H), 7.37 (d, J = 8.3 Hz, 1 arom. H), 7.25 (m, 1 arom.H), 7.16 (m, 1 arom.), 6.86 (d, J = 8.3 Hz, 1 arom. H), 6.60 (d, J = 8.3 Hz, 1 arom. H), 5.63 (s, H-C(5)), 5.17 and 5.06 (2 d, J = 6.6, 6.6 Hz, OCH2O), 3.42 (s, CH30).

Analysis calculated for C28H29N05. 0.2 MeOH (465.95): C 72.69, H 6.45, N 3.01; found: 72.58, H 6.28, N 3.00.

Example 2 Synthesis of 1 7-(Cydopropylmethyl)-6,7-dehydro-4,5o:-epoxy- 14-hydroxy-3- (methoxymethoxy)-6,7-2',3'-(N-methoxymethylindolo)morphinan (compound 2).

Sodium hydride (492 mg, 20.5 mmol; obtained from 820 mg of 60% dispersion in oil by washings with n-hexane) was added to a solution of naltrindole hydrochloride (1.5 g, 3.3

mmol) in 30 ml of anhydrous N,N-dimethyl formamide at 0° C. After stirring at 0° C for 15 min and additional 30 min at room temperature, the mixture was cooled again to 0° C and methoxymethyl bromide (1.27 g, 10.2 mmol) was added. After stirring at 0° C for 30 min, stirring was continued for another 120 min at room temperature. Methanol and H2O were added to destroy excess of sodium hydride. The mixture was extracted with ehtyl acetate (3 x 60 ml), the combined organic layers were washed with H20 (2 x 50 ml) and brine (2 x 50 ml) and evaporated to give a yellowish oil which was purified by column chromatography (silica gel, elution with CH2Cl2/MeOlllconc. NH40H 245:10:1) to afford 500 mg (30%) pure compound 2 as a colorless foam.

1H NMR (CDCl3): 67.44 (m, 2 arom. H), 7.20 (m, 1 arom. H), 7.07 (m, 1 arom. H), 6.82 (d, J = 8 Hz, 1 arom. H), 6.58 (J = 8 Hz), 5.81 (s, H-C(5)), 5.79 and 5.50 (2 d, J = 10.8, 10.8 Hz, NCH2O) 5.12 and 5.50 (2 d, J = 6.4, 6.4 Hz, OCH2O), 3.41 and 3.33 (2 s, CH30).

Analysis calculated for C30H34N2O5 (502.61): C 71.69, H 6.82, N 5.57; found: C 71.92, H 6.94, N 5.34.

Example 3 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro- 1 4-(2' ,6 -dichlorobenzyloxy)-4,5cc- epoxy-3 -(methoxymethoxy)-6,7-2' ,3' -benzo[b]furanomorphinan (compound 3).

Sodium hydride (36 mg, 1.5 mmol; obtained from 60 mg of 60% sodium hydride dispersion in oil by washings with n-hexane) was added to a solution of compound 1 (300 mg, 0.65 mmol) in 8 ml of anhydrous N,N-dimethylformamide at 0° C. After stirring at 0° C for 15 min, stirring was continued for another 30 min at room temperature and the mixture was cooled again to 0° C. 2,6-Dichlorobenzyl bromide (240 g, 1 mmol) was added at once and stirring was continued for 15 min at 0° C and then for 3 h at room temperature. Excess sodium hydride was destroyed with MeOH and H2O and the mixture was extracted with ethyl acetate (3 x 30 ml). The combined organic layers were washed with H2O (2 x 30 ml)

and brine (2 x 30 ml), dried over Na2SO4 and evaporated. The residue (400 mg colorless oil) was crystallized from MeOH to yield 300 mg (75%) of compound 3. M. p. 180-182° C.

1H NMR (CDC13): 8 7.41 (d, J = 8.3 Hz, 1 arom. H), 7.33 (d, J = 8.3 Hz, 1 arom. H), 7.23 (m, 1 arom. H), 7.14 (m, 2 arom. H), 7.03 and 7.01 (2 d, J = 7.3, 7.3 Hz, 2 arom. H), 6.84 (d, J = 8.3 Hz, 1 arom. H), 6.59 (d, J = 8.3 Hz, 1 arom. H), 5.56 (s, H-C(5)), 5.32 and 4.68 (2 d, J = 8.7, 8.7 Hz, OCH2Ph), 5.16 and 5.05 (2 d, J = 6.6, 6.6 Hz, OCH2O), 3.41 (s, CH30).

Example 4 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro- 1 4-(2' ,6' -dichlorobenzyloxy)-4,5ct- epoxy-3-hydroxy-6,7-2',3'-benzo[b]furanomorphinan (compound 4).

A solution of compound 3 (150 mg, 0.24 mmol) in MeOH (4 ml) and 1N HCl (2 ml) was refluxed for 1 h. After cooling, the solution was alkalized with conc. NH40H, extracted wiht ethyl acetate (3 x 15 ml), the combined organic layers were washed with H20 (2 x 15 ml) and brine (10 ml), dried over Na2SO4 and evaporated to give an oily residue which was crystallized from MeOH to yield 70 mg (51%) of compound 4. M. p. 193-195° C (dec.).

1H NMR (CDCl3): 6 7.42 (d, J = 8.3 Hz, 1 arom. H), 7.33 (d, J = 8 Hz, 1 arom. H), 7.24 (m, 1 arom. H), 7.14 (m, 2 arom. H), 7.03 and 7.01 (2 d, J = 7.3 Hz, 1 arom. H), 6.64 (d, J = 8.1 Hz, 1 arom. H), 6.56 (d, J = 8.1 Hz, 1 arom. H), 5.58 (s, H-C(5)), 5.32 and 4.68 (2 d, J = 8.6 Hz, OCH2Ph).

Analysis calculated for C33H29C12NO4 (574.51): C 68.79, H 5.09, N 2.44; found: C 68.97, H 5.05, N 2.44.

Example 5 Synthesis of 1 7-(Cyclopropylmethyl) -6,7-dehydro-4,5 a-epoxy-3 -(methoxymethoxy)- 14- (3'-nitrobenzyloxy)-6,7-2',3'-benzo[b]furanomorphinan (compound 5).

Sodium hydride (36 mg, 1.5 mmol; obtained from 60 mg of 60% sodium hydride dispersion in oil by washings with n-hexane) was added to a solution of compound 1 (300 mg, 0.65 mmol) in 6 ml of anhydrous N,N-dimethylformamide at 0° C. The resulting mixture was stirred at 0° C for 15 min and then at room temperature for another 30 min. After cooling to 0° C, 3-nitrobenzyl bromide (216 mg, 1 mmol) was added and stirring was continued first at 0° C for 15 min and then at room temperature for 3 h. Excess sodium hydride was destroyed by addition of MeOH and H20. The resulting mixture was extracted with ethyl acetate (3 x 30 ml), the combined organic layers were washed with H20 (2 x 20 ml) and brine (2 x 20 ml), dried over Na2SO4 and evaporated to give 380 mg of a brown oil which was purified by column chromatography (silica gel, elution with CH2C12/MeOH/conc.

NH40H 240:10:1) to afford 100 mg (26%) of compound 5 as colorless foam.

1H NMR (CDC13): 8 8.25 (s, 1 arom. H), 7.99 (m, 1 arom. H), 7.55 (d, J = 7.8 Hz, 1 arom.

H), 7.47 (d, J = 8.3 Hz, 1 arom. H), 7.28 (m, 4 arom. H), 7.15 (m, 1 arom. H), 6.87 (d, J = 8.3 Hz, 1 arom. H), 6.62 (d, J = 8.3 Hz, 1 arom. H), 5.66 (s, H-C(5)), 5.17 and 5.07 (2 d, J = 6.6 Hz, OCH2O, 4.92 and 4.44 (2 d, J = 11.5 Hz, OCH2Ph), 3.42 (s, CH30).

Example 6 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro-4,S-epoxy-3-hydroxy- 1 4-(3 '- nitrobenzyloxy)-6,7-2' ,3 -benzo [b] furanomorphinan Hydrochloride (compound 6).

A solution of compound 5 (80 mg, 0.13 mmol) in MeOH (4 ml) and 1N HCl (2 ml) was refluxed for 1 h. After cooling, the solution was alkalized with conc. NH40H, extracted with ethyl acetate (3 x 20 ml), the combined organic layers were washed with H20 (2 x 15 ml) and brine (15 ml), dried over Na2SO4 and evaporated. The oily residue was dissolved in

acetone and transformed into the hydrochloride salt (compound 6) by addition of ethereal HCl. Yield 50 mg (66%). M. p. > 230° C (dec.).

1H NMR (DMSO-d6): 8 9.40 (s, OH), 9.15 (broad s, +NH), 7.84 (s, 1 arom. H), 7.60 (d, J = 8.8 Hz, 1 arom. H), 7.53 (d, J = 7.6 Hz, 1 arom. H), 7.45 (d, J = 8 Hz, 1 arom. H), 7.23 (d, J = 7.6 Hz, 1 arom. H), 7.19 (d, J = 7.6 Hz, 1 arom. H), 6.98 (m, 1 arom. H), 6.88 (d, J = 7.6 Hz, 1 arom. H), 6.69 (d, J = 8.3 Hz, 1 arom. H), 6.66 (d, J = 8.3 Hz, 1 arom. H), 6.03 (s, H-C(5)), 4.98 and 4.87 (2 d, J = 14, 14 Hz, OCH2Ph).

Analysis calculated for C33H30N206 x HCl (587.08): C 67.52, H 5.32, N. 4.77; found: C 67.78, H 5.25, N 4. 76.

Example 7 Synthesis of 17-(Cyclopropylmethyl)-6,7-dehydro-4,5cc-epoxy-3-(methoxymet hoxy)-14-(2- naphthylmethoxy)-6,7-2',3'-benzo[b]furanomorphinan (compound 7).

Sodium hydride (36 mg, 1.5 mmol; obtained from 60 mg of sodium hydride dispersion in oil by washings with n-hexane) was added to a solution of compound 1 (300 mg, 0.65 mmol) in 5 ml of anhydrous N,N-dimethylformamide at 0° C. The resulting mixture was stirred at 0° C for 15 min and then at room temperature for another 30 min. After cooling to 0° C, 2- (bromomethyl)naphthalene (221 mg, 1 mmol) was added and stirring was continued at first at 0° C for 15 min and then at room temperature for 2 h. Excess sodium hydride was destroyed by addition of MeOH and H20. The resulting mixture was extracted with ethyl acetate (3 x 30 ml), the combined organic layers were washed with H20 (2 x 20 ml) and brine (2 x 10 ml), dried over Na2SO4 and evaporated to give a crystalline residue which was recrystallized to yield 285 mg (73%) of compound 7. M. p. 198-201° C.

1H NMR (CDCl3): 8 7.72-7.08 (m, 11 arom. H), 6.86 (d, J = 8.3 Hz, 1 arom. H), 6.62 (d, J = 8.3 Hz, 1 arom. H), 5.68 (s, H-C(5)), 5.17 and 5.07 (2 d, J = 6.6, 6.6 Hz, OCH2O), 5.01 and 4.57 (2 d, J = 11.2, 11.2 Hz, OCH2Ar), 3.42 (s, CH30).

Analysis calculated for C39H37NO5 x 0.2 EtOAc (C4HgO2) (617.35): C77.43, H 6.30, N 2.27; found: C 77.40, H 6.27, N 2.27.

Example 8 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro-4,5o:-epoxy-3-hydroxy- 14-(2' - naphthylmethoxy)-6,7-2' ,3 -benzo [b]furanomorphinan hydrochloride(compound 8).

A solution of compound 7 (180 mg, 0.3 mmol) in MeOH (5 ml) and 1N HCl (3 ml) was refluxed for 30 min, cooled and kept in the refrigerator overnight. The crystals formed were isolated and washed with small amounts of MeOH and ether to yield 150 mg (84%) of compound 8. M. p. > 215° C.

H NMR (DMSO-d6): 8 9.42 (s, OH), 9.00 (broad s, +NH), 7.68-6.85 (m, 11 arom. H), 6.71 (d, J = 8 Hz, 1 arom. H), 6.67 (d, J = 8 Hz, 1 arom. H), 6.04 (s, H-C(5)), 4.92 (s, OCH2Ar).

Analysis calculated for C37H33N04 x HCl. 0.3 MeOH (601.75): C74.45, H 5.90, N 2.33; found: C 74.47, H 5.76, N 2.35.

Example 9 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydroA,5oc-epoxy- 14-(2' -fluorobenzyloxy)-3- (methoxymethoxy)-6,7-2' ,3 -benzo [b]furanomorphinan (compound 9).

Sodium hydride (36 mg, 1.5 mmol; obtained from 60 mg of 60% sodium hydride dispersion in oil by washings with n-hexane) was added to a solution of compound 1 (300 mg, 0.65 mmol) in 5 ml of anhydrous N,N-dimethylformamide at 0° C. The resulting mixture was stirred at 0° C for 10 min and the at room temperature for another 30 min. After cooling to 0° C, 2-flourobenzyl bromide (120 1, 1 mmol) was added and stirring was continued at first at 0° C for 15 min and then at room temperature for 2 h. Excess sodium hydride was destroyed by addition of MeOH and H2O. The resulting mixture was extracted with ethyl

acetate (3 x 30 ml), the combined organic layers were washed with H20 (2 x 20 ml) and brine (2 x 20 ml), dried over Na2SO4 and evaporated to give an oil which purified by column chromatography (silica gel, elution with ethyl acetate/n-hexane 1)1:3 2) 1:1) to afford 215 mg (58%) of compound 9 as colorless foam.

1H NMR (DMSO-d6): 6 7.56 (d, J = 8 Hz, 1 arom. H), 7.49 (d, J = 8 Hz, 1 arom. H), 7.31 (m, 1 arom. H), 7.21 (m, 1 arom. H), 6.81 (d, J = 8.4 Hz, 1 arom. H), 6.67 (d, J = 8.4 Hz), 5.72 (s, H-C(5)), 5.06 and 5.01 (2 d, J = 6.4, 6.4 Hz, OCH2O), 4.89 and 4.57 (2 d, J = 11.6, 11.6 Hz, OCH2Ph), 3.33 (s, CH30).

Analysis calculated for C35H34NO5 (567.66): C 74.06, H 6.04, N 2.47; found: C 73.71, H 5.92, N 2.42.

Example 10 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro-4,Soc-epoxy- 14- (2' -fluorobenzyloxy)-3 - hydroxy-6,7-2' ,3 , -benzo[b]furanomorphinan Hydrochloride (compound 10).

A solution of compound 9 (160 mg, 0.28 mmol) in MeOH (3 ml) and 1N HCl (3 ml) was refluxed for 20 min, then cooled and kept in the refrigerator overnight. The crystals formed were isolated and washed with small amounts of MeOH and ether to yield 110 mg (70%) of compound 10. M. p. >215° C.

1H NMR (CDCl3): 8 9.45 (s, OH), 9.04 (broad s, +NH), 7.54 (d, J = 8.4 Hz, 1 arom. H, 7.31-6.73 (m, 7 arom. H), 6.71 (d, J = 8.2 Hz, 1 arom. H), 6.66 (d, J = 8.2 Hz, 1 arom. H), 5.98 (s, H-C(5)), 4.81 and 4.84 (2 d, J = 12 Hz, OCH2Ph).

Analysis calculated for C33H30FNO4 x HCl. 1.4 H2O (585.29): C 67.72, H 5.82, N 2.39; found: C 67.63, H 5.56, N 2.51.

Example 11 Synthesis of 1 4-(Cinnamyloxy)- 1 7-(cyclopropylmethyl)-6,7-dehydro-4,5o:-epoxy-3- (methoxymethoxy)-6,7-2' ,3 , -benzo[b]furanomorphinan (compound 11).

Sodium hydride (36 mg, 1.5 mmol; obtained from 60 mg of 60% sodium hydride dispersion in oil by washings with n-hexane) was added to a solution of compound 1 (300 mg, 0.65 mmol) in 5 ml of anhydrous N,N-dimethylformamide at 0° C. The resulting mixture was stirred at 0° C for 15 min and then at room temperature for another 30 min. After cooling to 0° C, cinnamyl bromide (197 mg, 1 mmol) was added and stirring was continued first at 0° C for 10 min and then at room temperature for 2 h. Excess sodium hydride was destroyed by addition of MeOH and H2O. The resulting mixture was extracted with ethyl acetate (3 x 30 ml), the combined organic layers were washed with H2O (2 x 20 ml) and brine (1 x 20 ml), dried over Na2SO4 and evaporated to give a crystalline residue which was treated with boiling methanol to afford 200 mg (53%) of compound 11. M. p. 156-159° C.

1H NMR (CDCl3): 6 7.47 (d, J = 8 Hz, 1 arom. H), 7.33 (d, J = 8 Hz, 1 arom. H), 7.28- 7.07 (m, 7 arom. H), 6.84 (d, J, 8.4 Hz, 1 arom. H), 6.59 (d, J = 8.4 Hz, 1 arom. H), 6.38 (d, J = 16 Hz, 1 olef. H), 6.13 (m, 1 olef. H), 5.68 (s, H-C(5)), 5.16 and 5.06 (2 d, J = 6.4, 6.4 Hz, OCH2O), 4.46 and 4.11(2 m, CH2O-C(14)), 3.42 (s, CH30).

Analysis calculated for C37H37N05. 0.1 EtOAc (584.52): C 76.85, H 6.52, N 2.40; found: C 76.70, H 6.48, N 2.41.

Example 12 Synthesis of 14-(Cinnamyloxy)- 1 7-(cyclopropylmethyl)-6,7-dehydro-4,Soc-epoxy-3- hydroxy-6,7-2' ,3' -benzo [b] furanomorphinan Salicylate (compound 12).

A solution of compound 11 (160 mg, 0.28 mmol) in MeOH (3 ml) and 1N HCl (3 ml) was refluxed for 1 h. After cooling, the solution was alkalized with conc. NH40H, extracted with ethyl acetate (3 x 15 ml), the combined organic layers were washed with H2O (2 x 15

ml) and brine (10 ml), dried over Na2SO4 and evaporated to give a colorless foam (100 mg). To a solution of this foam in a small amount of methanol 30 mg of salicyclic acid were added, the crystals formed collected and washed with cold methanol to yield 100 mg (53%) of compound 12. M. p. > 170 C.

1H NMR (CDCl3): 8 7.94 (d, J = 8 Hz, 1 arom. H), 7.35 (d, J = 8 Hz, 1 arom. H), 7.30- 6.73 (m, 12 arom. H), 6.56 (d, J = 8 Hz, 1 arom. H), 5.96 (s, 2 olef. H), 5.55 (s, H-C(5)), 4.33-4.02 (m, CH2O-C(14)).

Analysis calculated for C35H33N04. Salicyclic acid (C7H603). 1 MeOH (701.82): C 73.57, H 6.18, N 2.00; found: C 73.56, H 5.96, N 2.06.

Example 13 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro-4,5 epoxy- 1 4-methoxy-3- (methoxymethoxy)-6,7-2' ,3 , -benzo[b]furanomorphinan (compound 13).

Sodium hydride (36 mg, 1.5 mmol; obtained from 60 mg of 60% sodium hydride dispersion in oil by washings with n-hexane) was added to a solution of compound 1 (300 mg, 0.65 mmol) in 5 ml of anhydrous N,N-dimethylformamide at 0° C. The resulting mixture was stirred at 0° C for 15 min and the at room temperature for another 30 min. After cooling to 0° C, dimethyl sulfate (100 CI1, 1 mmol) was added and stirring was continued at first at 0° C for 15 min and then at room temperature for 2 h. Excess sodium hydride was destroyed by addition of MeOH and H2O. The resulting mixture was extracted with ethyl acetate (3 x 30 ml), the combined organic layers were washed with H2O (2 x 20 ml) and brine (2 x 20 ml), dried over Na2SO4 and evaporated to give a colorless foam (280 mg) of compound 13 which was pure by TLC and NMR.

H NMR (DMSO-d6): 6 7.56 (d, J = 8 Hz, 1 arom. H), 7.52 (d, J = 8 Hz, 1 arom. H), 7.32 <BR> <BR> <BR> <BR> <BR> (dd, J = 8, 8 Hz, 1 arom. H), 7.23 (dd, J = 8, 8 Hz, 1 arom. H), 6.79 (d, J = 8.2 Hz, 1 arom.

H), 6.64 (d, J = 8.2 Hz, 1 arom. H), 5.64 (s, H-C(5)), 5.05 and 5.00 (2 d, J = 6.4, 6.4 Hz, OCH2O), 3.32 (CH30).

Analysis calculated for C29H31N05. 0.2 MeOH (479.98): C 73.07, H 6.68, N 2.92; found: C 72.94, H 6.60, N 2.92.

Example 14 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro-4,Soc-epoxy-3-hydroxy- 1 4-methoxy-6,7- 2' ,3 -benzo[b]furanomorphinan Hydrochloride (compound 14).

A solution of compound 13 (160 mg, 0.28 mmol) in MeOH (3 ml) and 1N HCl (2 ml) was refluxed for 20 min, then cooled and kept in the refrigerator overnight. The crystals formed were isolated and washed with small amounts of MeOH and ether to yield 70 mg (36%) of compound 14. M. p. > 240° C.

H NMR (DMSO-d6): 6 9.47 (s, OH), 9.17 (broad s, +NH), 7.61 (d, J = 8 Hz, 1 arom. H), 7.53 (d, J = 8 Hz, 1 arom. H), 7.36 (dd, J = 8, 8 Hz, 1 arom. H), 7.27 (dd, J = 8, 8 Hz, 1 arom. H), 6.72 (d, J = 8.4 Hz, 1 arom. H), 6.65 (d, J = 8.4 Hz, 1 arom. H), 5.90 (s, H- C(5)), 3.35 (s, CH30).

Analysis calculated for C27H27N04 x HCl. 1.5 H20 (493.00): C 65.78, H 6.34, N 2.84; found: C 65.89, H 6.20, N 2.85.

Example 15 Synthesis of 1 7-(Cyclopropylmethyl)- 1 4-(2' -chlorobenzyloxy)-6,7-dehydro-4,5 oc-epoxy-3 - (methoxymethoxy)-6,7-2',3'-(N-methoxymethylindolo)morphinan (compound 15).

Sodium hydride (36 mg, 1.5 mmol; obtained from 60 mg of 60% sodium hydride dispersion in oil by washings with n-hexane) was added to a solution of compound 2 (327 mg, 0.65 mmol) in 5 ml of anhydrous N,N-dimethylformamide at 0° C. The resulting mixture was stirred at 0° C for 15 min and then at room temperature for another 30 min. After cooling to 0° C, 2-chlorobenzyl bromide (205 mg, 1 mmol) was added and stirring was continued first at 0° C for 15 min and then at room temperature for 3 h. Excess sodium hydride was destroyed by addition of MeOH and H2O. The resulting mixture was extracted with ethyl acetate (3 x 30 ml), the combined organic layers were washed with H20 (2 x 40 ml) and brine (2 x 30 ml), dried over Na2SO4 and evaporated to give 370 mg of compound 15 as colorless foam which was pure by TLC and NMR.

1H NMR (CDC13): 67.56 (m, 1 arom. H), 7.44 (m, 1 arom. H), 7.37-7.17 (m, 3 arom. H), 7.01 (m, 1 arom. H), 6.91 (m, 1 arom. H), 6.83 (d, J = 8.2 Hz, 1 arom. H), 6.59 (d, J = 8.2 Hz, 1 arom. H), 5.90 (s, H-C(5)), 5.82 and 5.55 (2 d, J = 11.2, 11.2 Hz, NCH2O), 5.13 and 5.03 (2 d, J = 6.4, 6.4 Hz, OCH2O), 4.98 and 4.56 (2 d, J = 13, 13 Hz, OCH2Ph), 3.40 and 3.26 (2 s, 2 CH30).

Example 16 Synthesis of 17-(Cyclopropylmethyl)-14-(2'-chlorobenzyloxy)-6,7-dehydro-4 ,5a-epoxy-3- hydroxy-6,7-2' ,3'-indolomorphinan Hydrochloride (compound 16).

A solution of compound 15 (300 mg, 0.48 mmol) in MeOH (5 ml) and 1N HCl (3 ml) was refluxed for 1 h. After cooling, the solution was alkalized with conc. NH40H, extracted with ethyl acetate (3 x 20 ml), the combined organic layers were washed with H2O (2 x 20 ml) and brine (20 ml), dried over Na2SO4 and evaporated to give a colorless oil. To a solution of this foam in a small amount of methanol ethereal HCl was added, the crystals

formed collected and washed with cold methanol to yield 120 mg (43%) of compound 16.

M. p. > 250O C (dec.).

1H NMR (DMSO-d6): 8 11.38 (s, NH), 9.38 (s, OH), 8.76 (broad s, *NH), 7.34-6.85 (m, 8 arom. H), 6.72 (d, J = 8 Hz, 1 arom. H), 6.64 (d, J = 8 Hz, 1 arom. H), 5.93 (s, H-C(5)), 4.80 and 4.67 (2 d, J = 13, 13 Hz, OCH2Ph).

Analysis calculated for C33H31N203 x HCl. (575.54): C 68.87, H 5.60, N 4.87; found: C 68.81, H 5.59, H 4.77.

Example 17 Synthesis of 17-(Cyclopropylmethy1)-6,7-dehydro-3, 14-dimethoxy-4,5a-epoxy-6,7-2' ,3'- benzo[b] furanomorphinan (compound 17).

Sodium hydride (144 mg, 6 mmol; obtained from 240 mg of 60% sodium hydride dispersion in oil by washings with n-hexane) was added to a solution of naltriben methane-sulfonate (500 mg, 0.97 mmol) in 10 ml of anhydrous N,N-dimethylformamide at 0° C. The resulting mixture was stirred at 0° C for 15 min and then at room temperature for another 30 min.

After cooling to 0° C, dimethyl sulfate (380 cm1, 4 mmol) was added and stirring was continued first at 0° C for 30 min and then at room temperature for 3 h. Excess sodium hydride was destroyed by addition of MeOH and H2O. The resulting mixture was extracted with ethyl acetate (3 x 40 ml), the combined organic layers were washed with H20 (2 x 30 ml) and brine (2 x 30 ml), dried over Na2SO4 and evaporated to give a crystalline residue which was recrystallized from MeOH to afford 320 mg (74%) of compound 17. M. p. 221- 2240 C (dec.).

HNMR (CDCl3): 6 7.47-7.14 (m, 4 arom. H), 6.64 (d, J = 8.4 Hz, 1 arom. H), 6.59 (d, J = 8.4 Hz, 1 arom. H), 5.62 (s, H-C(5)), 3.78 (s, CH30-C(3)), 3.31 (s, CH30-C(14)).

Analysis calculated for C28H29NO4. 0.3 MeOH (453.16): C 75.01, H 6.72, N 3.09; found: C 74.97, H 6.68, N 3.05.

Example 18 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro-4,5 oc-epoxy-3-hydroxy- 1 4-(3 ' - chlorobenzyloxy)-6,7-2' ,3 , -benzo[b]furanomorphinan Hydrochloride (compound 19).

To a stirred solution of naltriben methanesulfonate (256 mg, 0.5 mmol) in anhydrous N,N- dimethyl formamide (10 ml) was added sodium hydride (60% dispersion in oil, 60 mg, 1.5 mmol) at 0° C. The solution was stirred for 1 h at 20° C and then cooled to 0° C prior to addition of bromomethyl methyl ether (125 mg, 1.0 mmol). The mixture was warmed up to room temperature during 1 h and cooled again to 0° C before sodium hydride (60% dispersion in oil, 100 mg, 2.5 mmol) was added. After 1 h, 3-chlorobenzyl bromide (308 mg, 1.5 mmol) was added to the solution and the resulting mixture was stirred for 4 h at 200 C, and then 5 ml of methanol and 5 ml ethyl acetate were slowly added at 0° C, followed by addition of saturated aqueous NH4Cl solution (20 ml). The mixture was extracted with ethyl acetate (3 x 50 ml), the combined organic layers were washed with brine, dried over MgSO4, and evaporated to give crude 17-(cyclopropylmethyl)-6,7-dehydro-4,5a-epoxy-3- (methoxymethoxy)- 1 4-(3 ' -chlorobenzyloxy)-6,7-2', 3, -benzo[b]furanomorphinan (compound 18). This crude product was dissolved in 5 ml of ethanol and 1.5 ml of 1N hydrochloric acid and refluxed for 1 h. The reaction mixture was alkalized with 1N aqueous NH40H solution, extracted with ethyl acetate (3 x 50 ml), the combined organic layers were washed with brine, dried over MgSO4, and concentrated to give a crude product which was purified by silica gel column chromatography (hexane: CHCl3 (75:25-->50:50-->25:75-->100:0) oCHCl3:AcOEt (80:20e50:50o0:100) to afford the title compound as the free base (colorless oil; 232 mg, 86%). H NMR (CDCl3): 8 7.50-7.05 (m, 8 arom. H), 6.69 (d, J = 8.4 Hz, 1 arom. H), 6.58 (d, J = 8.4 Hz, 1 arom. H), 5.68 (s, H-C(5)), 4.81 and 4.35 (2 d, J = 11.6, 11.6Hz, OCH2(3'-ClPh)). A solution of this free base in anhydrous diethyl ether (5 ml) was treated with HCl/ether solution (1M, 2 ml) at 0° C. Isolation of the precipitate provided the title compound 19 as a solid. M. p. >230° C

(dec.). H NMR (DMSO-d6): 8 9.40 (s, OH), 8.59 (broad s, +NH), 7.53-6.90 (m, 8 arom.

H), 6.65 (s, 2 arom. H) 6.03 (s, H-C(5)), 4.74 and 4.62 (2 d, J = 13.6, 13.6 Hz, OCH2(3'- ClPH)). Analysis calculated for C33H30C1N04. HCl. 1.5 H2O: C 65.67, H 5.68, N 2.32; found: C 65.31, H 5.37, N 2.33.

Example 19 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro-4,5a-epoxy-3-hydroxy- 14-(2' - chlorobenzyloxy)-6,7-2' ,3'-benzo[b]furanomorphinan Hydrochloride (compound 21).

To a stirred solution of naltriben methanesulfonate (256 mg, 0.5 mmol) in anhydrous N,N- dimethyl formamide (10 ml) was added sodium hydride (60% dispersion in oil, 100 mg, 2.5 mmol) at 0° C. The solution was stirred for 1 h at 200 C and then cooled to 0° C prior to addition of bromomethyl methyl ether (125 mg, 1.0 mmol). The mixture was warmed up to room temperature during 1 h and cooled again to 0° C before sodium hydride (60% dispersion in oil, 100 mg, 2.5 mmol) was added. After 1 h, 2-chlorobenzyl bromide (205 mg, 1.0 mmol) was added to the solution and the resulting mixture was stirred for 12 h at 20° C, and then 5 ml of methanol and 5 ml ethyl acetate were slowly added at 0° C, followed by addition of saturated aqueous NH4Cl solution (20 ml). The mixture was extracted with ethyl acetate (3 x 50 ml), the combined organic layers were washed with brine, dried over MgSO4, and concentrated to give crude 17-(cyclopropylmethyl)-'6,7- dehydro-4,5a-epoxy-3-(methoxymethoxy)- 14-(2'-chlorobenzyloxy)-6,7-2', 3 ' - benzo[b]furanomorphinan (compound 20). This crude product was dissolved in 5 ml of ethanol and 2 ml of 1N hydrochloric acid and refluxed for 2 h. The reaction mixture was alkalized with 1N aqueous NH40H solution, extracted with ethyl acetate (3 x 50 ml), the combined organic layers were washed with brine, dried over MgSO4, and evaporated to give a crude product which was purified by silica gel column chromatography (hexane: CHCl3 (75:2550:5025:75100:0) to afford the title compound as the free base (colorless oil; 236 mg, 87%). 1H NMR (CDCl3): 67.45-6.90 (m, 8 arom. H), 6.72 (d, J = 8.4 Hz, 1 arom. H), 6.68 (d, J = 8.4 Hz, 1 arom. H), 5.72 (s, H-C(5)), 4.96 and 4.55 (2 d, J = 11.6, 11.6 Hz, OCH2(2' -ClPh)). A solution of this free base in (5 ml) of anhydrous

diethyl ether was treated with HCl/ether solution (1M, 2 ml) at 0° C. Isolation of the precipitate provided the title compound as a solid. M. p. >220° C.

1H NMR (DMSO-d6): 8 9.40 (s, OH), 8.59 (broad s, +NH), 7.56-6.90 (m, 8 arom. H), 6.66 (s, 2 arom. H) 6.03 (s, H-C(5)), 4.74 (s, OCH2(2'-ClPh)).

Analysis calculated for C33H30ClNO4 x HCl. 1.5 H20: C 65.67, H 5.68, N 2.32; found: C 65.72, H 5.48, N 2.25.

Example 20 Synthesis of 14-Allyloxy- 1 7-(cyclopropylmethyl) -6,7-dehydro-4,5 a-epoxy-3-hydroxy- 1 ' - allyl-6,7-2' ,3'-indolomorphinan Hydrochloride (compound 22).

Dimethyl isobutylsilyl chloride (114 mg, 0.75 mmol) was added at 0° C to a stirred solution of naltrindole methanesulfonate (255 mg, 0.5 mmol) and diisopropyl ethylamine (260 mg, 2.0 mmol) in anhydrous N,N-dimethyl formamide (10 ml). The resulting solution was stirred at 20° C for 1 h and then cooled to 0° C prior to the addition of sodium hydride (60% dispersion in oil, 120 mg, 3.0 mmol). After 1 h, dimethyl isobutylsilyl chloride (114 mg, 0.75 mmol) was added to the mixture. The resulting mixture was stirred for 1 h at 200 C and then cooled to 0° C before adding sodium hydride (60% dispersion in oil, 120 mg, 3.00 mmol). After 1 h allyl bromide (1.51 mg, 1.25 mmol) was added. The reaction mixture was stirred for 2 h at 20° C and then quenched with saturated aqueous NH4Cl solution and extracted with ethyl acetate (3 x 30 ml). The combined organic layers were washed with brine, dried over MgSO4, and evaporated to give a yellow oil which was dissolved in methanol (6 ml) and 1 N hydrochloric acid (2 ml) and refluxed for 6 h. The reaction mixture was alkalized with 1N NH40H solution, extracted with ethyl acetate (3 x 30 ml), the combined organic layers were washed with brine, dried over MgSO4, and evaporated. This crude product was purified by silica gel column chromatography (hexane: CHCl3 (75:2550:50) oCHCl3:AcOEto (75:25e50:50eAcOEt) to give the title compound as the free base (colorless oil; 106 mg).

H NMR (CDCl3): 87.40 (d, J = 8.4 Hz, 1 arom. H), 7.24 (m, 1 arom. H), 7.15 (m, 1 arom. H), 7.03 (m, 1 arom. H), 6.57 (d, J = 8.4 Hz, 1 arom. H), 6.50 (d,J = 8.4 Hz, 1 arom.

H), 6.08 (m, 1 olef. H), 5.76 (m, 1 olef. H), 5.72 (s, H-C(5)), 5.15-4.75 (m, 6 H, CH2N, 2 CH2 = C), 4.24 and 3.92 (2 dd, J = 12.4, 4.8 Hz, CH2O).

The free base was dissolved in diethyl ether (5 ml) and treated with HCl/ether solution (1M, 2 ml) at 0° C. Isolation of the precipitate provided the title compound 22 as a solid.

Example 21 Synthesis of 17 -(Cyclopropylmethyl)-6 ,7-dehydro-4 ,5 oc-epoxy-3-hydroxy- 1 4-allyloxy- 6,7,2' , 3, -indolomorphinan Hydrochloride (compound 23) To a stirred solution of naltrindole hydrochloride (220 mg, 0.5 mmol) in anhydrous N,N- dimethyl formamide (10 ml) was added sodium hydride (60% dispersion in oil, 160 mg, 4.0 mmol) at OOC. The solution was stirred for 1 h at 200 C, and then cooled to 0° C prior to addition of bromomethyl methyl ether (250 mg, 2.0 mmol). The mixture was warmed up to r.t. during one hour and cooled again to 0° C before sodium hydride (60%, 100 mg, 2.5 mmol) was added. After 1 h allyl bromide (242 mg, 2.0 mmol) was added to the solution and the resulting mixture was stirred for 4 h at 200 C, and then 5 ml methanol and 5 ml ethyl acetate were slowly added at 0° C, followed by addition of saturated aqueous NH4Cl solution (20 ml). The mixture was extracted with ethyl acetate (3x50 ml), the combined organic layers were washed with brine, dried over MgSO4, and evaporated to give crude product, which was dissolved in 5 ml ethanol/l ml 6N hydrochloric acid and refluxed for 2 hrs. The reaction mixture was alkalized with 1N aqueous NH40H solution, extracted with ethyl acetate (3.50 ml), the combined organic layers were washed with brine, dried over MgSO4, and concentrated to give a crude product, which was purified by silica gel column chromatography (Hexane: CHCl3 (75:25-->50:50-->25:75-->0:100) oCHC13: AcOEt (75:2550:500: 100)) to afford compound 23 (53 mg, 23%) as the free base (colorless

oil). H NMR (CDCl3): 8 7.50-7.00 (m, 4 arom. H), 6.65-6.45 (m, 2 arom. H), 5.80 (m, 1H, CH=C), 5.75 (s, H-C(5)), 5.18-4.85 (m, C=CH2), 4.25 & 3.95 (m, OCH2).

A solution of this free base (53 mg) in anhydrous ethyl ether (5 ml) was treated with HCl/ether solution (1M, 1 ml) at 0° C. Isolation of the precipitate provided the title compound 23 as a solid (hydrochloride salt). M.p. 270-285° C (dec.). IR (HCl salt, KBr) <BR> <BR> -1<BR> <BR> 3087 (m), 2846 (m), 1623 (s), 1505 (s), 1462 (s), 1330 (s), 1166 (s), 922 (s) cm Example 22 Synthesis of 17-Cyclopropylmethyl-6,7-dehydro-4,5a-epoxy-3-hydroxy- 14-benzyloxy- 6,7,2' ,3' -benzo[b]foranomorphinan Hydrochloride (compound 24): To a stirred solution of naltriben methanesulfonate (256 mg, 0.5 mmol) and N,N- diisopropylethylamine (260 mg, 2.0 mmol) in anhydrous N,N-dimethyl formamide (10 ml) was added triisopropylsilyl chloride (145 mg, 0.75 mmol) at OOC. The solution was stirred for 1 h at 20° C, and then cooled to 0° C prior to addition of sodium hydride (60%, 120 mg, 3.0 mmol) was added. After 1 h, benzyl bromide (171 mg, 1.0 mmol) was dropwise added to the solution. The resulting mixture was stirred for 2 h at 200 C, and then 5 ml methanol and 5 ml ethyl acetate were slowly added at 0° C. After 30 min the mixture was extracted with ethyl acetate (3x50 ml). The combined organic layers were washed with brine, dried over MgS04, and concentrated to a yellow oil, which was purified by silica gel column chromatography (Hexane: CHCl3 (75:2560:40)Hexane: AcOEt (75:25<50:50)) to afford compound 24 (206 mg, 82%) as the free base (colorless oil). H NMR (CDCl3): 8 7.60-7.05 (m, 9 arom. H), 6.80-6.60 (m, 2 arom. H), 5.72 (s, H-C(5)), 4.95 and 4.52 (2 d, J=11.6, 11.6 Hz, OCH2Ph).

A solution of this free base in anhydrous ethyl ether (5 ml) was treated with HCl/ether solution (1M, 1 ml) at 0° C. Isolation of the precipitate provided the title compound 24 as a solid (hydrochloride salt). M.p. 255-270° C (dec.). IR (HCl salt, KBr) 3642 (m), 3174 (s), <BR> <BR> -1<BR> <BR> 2936 (s), 1616 (s), 1500 (s), 1457 (s), 1309 (s), 1068 (s), 932 (s) cm . Analysis calculated

for C33H31N04. HCl. 0.80 H2O: C 71.23, H 6.09, N, 2.52. Found: C 71.32, H 5.78, N 2.35.

Example 23 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydro-4, S oc-epoxy-3-hydroxy- 1 4-allyloxy- 6,7,2',3' -benzo[b]foranomorphinan Hydrochloride (compound 25) To a stirred solution of naltriben methanesulfonate (256 mg, 0.5 mmol) and N,N- diisopropylethylamine (260 mg, 2.0 mmol) in anhydrous N,N-dimethyl formamide (10 ml) was added triisopropylsilyl chloride (145 mg, 0.75 mmol) at 0°C. The solution was stirred for 1 h at 20° C, and then cooled to 0° C prior to addition of sodium hydride (60%, 120 mg, 3.0 mmol) was added. After 1 h, allyl bromide (363 mg, 3.0 mmol) was dropwise added to the solution. The resulting mixture was stirred for 2 h at 200 C, and then 5 ml methanol and 5 ml ethyl acetate were slowly added at 0° C. After 30 min the mixture was extracted with ethyl acetate (3x50 ml). The combined organic layers were washed with brine, dried over MgSO4, and concentrated to a yellow oil, which was dissolved in MgSO4, and concentrated to a yellow oil, which was dissolved in 10 ml ethanol/2.0 ml 1N hydrochloric acid and refluxed for 5 hrs. The reaction mixture was alkalized with 1N aqueous NH40H solution, extracted with ethyl acetate (3x50 ml). The combined organic layers were washed with brine, dried over MgSO4, and concentrated to give a crude product, which was purified by silica gel column chromatography (Hexane: CHCl3 (75:25o50:50)oCHCl3: AcOEt (75:25<50:50eAcOEt)) to afford compound 25 (106 mg, 46%) as the free base (colorless oil). H NMR (CDCl3): 87.50-7.08 (m, 4 arom. H), 6.70-6.45 (m, 2 arom. H), 5.75 (m, 1H, CH=C) 5.65 (s, H-C(5)), 5.18-4.82 (m, 2H), 4.81 (br s, OH), 4.25 and 3.90 (m, OCH2).

A solution of this free base in anhydrous ethyl ether (5 ml) was treated with HCl/ether solution (1M, 1 ml) at 0° C. Isolation of the precipitate provided the title compound 25 as a solid (hydrochloride salt). M.p. 280-290° C (dec.). IR (HCl salt, KBr) 3642 (m), 2948 (s),

-1<BR> <BR> 1641 (s), 1500 (s), 1375 (s), 1315 (s), 996 (s) 920 (s) cm . Analysis calculated for C29H29N04. HCl. 1.1 H2O: C 68.05, H 6.34, N, 2.74. Found: C 67.94, H 5.95, N 2.53.

Example 24 Synthesis of 1 7-(Cyclopropylmethyl)-6,7-dehydw-4,5oc-epoxy-3-hydroxy- 14-crotyloxy- 6,7,2' ,3 '-benzo[b] foranomorphinan Hydrochloride (compound 26) To a stirred solution of naltriben methanesulfonate (256 mg, 0.5 mmol) and N,N- diisopropylethylamine (260 mg, 2.0 mmol) in anhydrous N,N-dimethyl formamide (10 ml) was added triisopropylsilyl chloride (145 mg, 0.75 mmol) at OOC. The solution was stirred for 1 h at 20° C, and then cooled to 0° C prior to addition of sodium hydride (60%, 120 mg, 3.0 mmol) was added. After 1 h, crotyl bromide (405 mg, 3.0 mmol) was dropwise added to the solution. The resulting mixture was stirred for 2 h at 200 C, and then 5 ml methanol and 5 ml ethyl acetate were slowly added at 0° C. After 30 min the mixture was extracted with ethyl acetate (3x50 ml). The combined organic layers were washed with brine, dried over MgSO4, and concentrated to a yellow oil, which was dissolved in 10 ml ethanol/2 ml 1 N hydrochloric acid and refluxed for 5 hrs. The reaction mixture was alkalized with 1N aqueous NH40H solution, extracted with ethyl acetate (3x50 ml). The combined organic layers were washed with brine, dried over MgSO4, and concentrated to give a crude product, which was purified by silica gel column chromatography (Hexane: CHCl3 (75:25e50:50)eCHCl3: AcOEt (75:25e50:50eAcOEt)) to afford compound 26 (45 mg, 19%) as the free base (colorless oil). 1H NMR (CDCl3): 87.48-7.08 (m, 4 arom.

H), 6.66-6.48 (m, 2 arom. H), 5.62 (s, H-C(5)), 5.40 (m, 2H, CH=CH), 4.20 and 3.82 (m, OCH2), 1.48 & 1.52 (m, 3H, Me).

A solution of the free base in anhydrous ethyl ether (5 ml) was treated with HCl/ether solution (1M, 1 ml) at 0° C. Isolation of the precipitate provided the title compound 26 as a solid in form of its hydrochloride salt. Mp. 245-260 C (dec.). IR (Hcl salt, Kbr): 3642 (m), <BR> <BR> -1 <BR> <BR> 3024 (s), 1640 (s), 1503 (s), 1325 (s), 927 (s) cm