Patent ID: 7842813

Claim:
A process for preparing a compound of formula (I): wherein R 1 , R 2 , R 3 and R 4 are each independently selected from: (a) hydrogen; or (b) NH 2; or one of R 1 and R 2 and/or one of R 3 and R 4 is hydrogen and the other of R 1 and R 2 and/or the other of R 3 and R 4 is selected from: (a) C(O)R 5 , where R 5 is C 1 -C 6 alkyl, optionally substituted with one or more substituents selected from aryl, substituted aryl, heteroaryl, or substituted heteroaryl; (b) C(O)OR 5 , where R 5 is as previously defined; alternatively, R 1 and R 2 and/or R 3 and R 4 are taken together with the nitrogen atom to which they are attached to form (a) wherein A and B are each independently hydrogen, a substituted or unsubstituted aliphatic group, a substituted or unsubstituted cyclic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted alicyclic group, or a substituted or unsubstituted heteroaryl group; or A and B taken together with the carbon to which they are attached form a cyclic moiety selected from: aryl, substituted aryl, heterocyclic, substituted heterocyclic, alicyclic, or substituted alicyclic; b) N═C(R 6 )(R 7 ), where R 6 and R 7 are each independently selected from a substituted or unsubstituted aliphatic group, a substituted or unsubstituted cyclic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted aryl group, a substituted or unsubstituted alicyclic group, or a substituted or unsubstituted heteroaryl group; said process comprising of the following steps: (1) halogenating 6-hydroxymethyl-nicotinic acid methyl ester (III) with a chlorinating reagent to form a compound of formula (IV): (2) treating the compound of formula (IV) with a compound of formula R 1 R 2 NOH, wherein R 1 and R 2 are as previously defined, in the presence of base to yield a compound of formula (V): (3) reacting the compound of formula (V) with liquid ammonia or ammonium hydroxide to provide a compound of formula (VI); (4) reacting the compound of formula (VI) with a thionating reagent to provide a compound of formula (VII): (5) reacting the compound of formula (VII) with XCH 2 CONR 3 R 4 , where X is a leaving group, to provide the compound of formula (I):