Patent ID: 7183414

Claim:
A process for preparing a compound of the formula I or a pharmaceutically acceptable salt, prodrug, hydrate or solvate thereof; wherein each R 1 , R 2 , and R 3 is independently selected from the group consisting of H, (C 1 –C 6 )alkyl, (C 3 –C 6 )cycloalkyl, halo, cyano, CF 3 , difluoromethoxy, trifluoromethoxy, —O(C 1 –C 6 )alkyl, —O(C 3 –C 6 )cycloalkyl, and —NR 12 R 13 ; wherein R 4 is —(CR 5 R 6 ) m H, or —(CR 7 R 8 ) n (4 to 10 membered)-aromatic or nonaromatic heterocyclic containing one or more heteroatoms each selected from O, S and N, wherein m is an integer ranging from 1 to 5, wherein n is an integer ranging from 0 to 5, wherein said 4 to 10 membered heterocyclic when aromatic is optionally substituted by 1 to 3 R 9 substituents, and wherein said 4 to 10 membered heterocyclic when non-aromatic is optionally substituted by 1 to 3 R 10 substituents at any position and optionally substituted by 1 to 3 R 11 substituents at any position not adjacent to or directly attached to a heteroatom; wherein each R 5 , R 6 , R 7 and R 8 are independently selected from the group consisting of H and (C 1 –C 6 )alkyl; wherein each R 9 is independently selected from H, (C 1 –C 6 )alkyl, (C 3 –C 6 )cycloalkyl, halo, cyano, CF 3 , difluoromethoxy, trifluoromethoxy, —O(C 1 –C 6 )alkyl, —O(C 3 –C 6 )cycloalkyl, and —NR 14 R 15 ; wherein each R 10 is independently selected from H, (C 1 –C 6 )alkyl, and (C 3 –C 6 )cycloalkyl; wherein each R 11 is independently selected from halo, cyano, CF 3 , difluoromethoxy, trifluoromethoxy, —O(C 1 –C 6 )alkyl, —O(C 3 –C 6 )cycloalkyl, and —NR 16 R 17 ; wherein R 12 , R 13 , R 14 , R 15 , R 16 and R 17 are independently selected from the group consisting of H, (C 1 –C 6 )alkyl, and (C 3 –C 6 )cycloalkyl; wherein each of the aforesaid (C 1 –C 6 )alkyl, (C 3 –C 6 )cycloalkyl, —O(C 1 –C 6 )alkyl and —O(C 3 –C 6 )cycloalkyl substituents wherever they occur may optionally be independently substituted by one to three substituents independently selected from the group consisting of halo, cyano, amino, (C 1 –C 6 )alkylamino, [(C 1 –C 6 )alkyl] 2 -amino, perhalo(C –C 6 )alkyl, perhalo(C 1 –C 6 )alkoxy, (C 1 –C 6 )alkyl, (C 2 –C 6 )alkenyl, (C 2 –C 6 )alkynyl, hydroxy, and (C 1 –C 6 )alkoxy; comprising reacting a compound of the formula II wherein BOC is t-butoxycarbonyl, and R 1 , R 2 , R 3 and R 4 are as defined above for the compound of formula I, with a metal alkoxide in the presence of water to give a compound of the formula I.