Patent ID: 6911549

Claim:
A process of preparing a compound of formula: wherein R 1 is selected from the group consisting of —CH 3 , —C 6 H 5 or phenyl substituted with one, 2 or 3 C 1 -C 4 alkyl, C 1 -C 3 alkoxy, halo, C 1 -C 3 alkylthio, trifluoromethyl, C 2 -C 6 dialkylamino, hydroxy or nitro, and -2-furyl, 2-thienyl, 1-naphthyl, 2-naphthyl or 3,4-methylenedioxyphenyl; R 2 is selected from the group consisting of —H, —NHC(O)H, —NHC(O)C 1 -C 10 alkyl, —NHC(O)phenyl, —NHC(O)phenyl substituted with one, 2 or 3 C 1 -C 4 alkyl, C 1 -C 3 alkoxy, halo, C 1 -C 3 alkylthio, trifluoromethyl, C 2 -C 6 dialkylamino, hydroxy or nitro, —NHC(O)(CH 3 )═CHCH 3 , —NHC(O)OC(CH 3 ) 3 , —NHC(O)OCH 2 phenyl, —NH 2 , —NHSO 2 -4-methylphenyl, —NHC(O)(CH 2 ) 3 COOH, —NHC(O)-4-(SO 3 H)phenyl, —OH, —NHC(O)-1-adamantyl, —NHC(O)O-3-tetrahydrofuranyl, —NHC(O)O-4-tetrahydropyranyl, —NHC(O)CH 2 C(CH 3 ) 3 , —NHC(O)C(CH 3 ), —NHC(O)OC 1 -C 10 alkyl, —NHC(O)NHC 1 -C 10 alkyl, —NHC(O)NHPh, —NHC(O)NHPh substituted with one, 2 or 3 C 1 -C 4 alkyl, C 1 -C 3 alkoxy, halo, C 1 -C 3 alkylthio, trifluoromethyl, C 2 -C 6 dialkylamino, or nitro, —NHC(O)C 3 -C 8 cycloalkyl, —NHC(O)C(CH 2 CH 3 ) 2 CH 3 , —NHC(O)C(CH 3 ) 2 CH 2 C1, —NHC(O)C(CH 3 ) 2 CH 2 CH 3 , phthalimido, —NHC(O)-1-phenyl-1-cyclopentyl, —NHC(O)-1-methyl-1-cyclohexyl, —NHC(S)NHC(CH 3 ) 3 , —NHC(O)NHCC(CH 3 ) 3 and —NHC(O)NHPh; R 3 is selected from the group consisting of —H, —NHC(O)phenyl and —NHC(O)OC(CH 3 ) 3 , with the overall proviso that one of R 2 and R 3 is —H but R 2 and R 3 are not both —H; Bz is —C(O)phenyl; and Ac is C(O)CH 3 ; which comprises reacting a compound of formula: wherein R 1 , R 2 , R 3 Bz and Ac are as defined above; with hydrazine.