Process for preparing 4-substituted-1H-indole-3-glyoxamides

Described are processes for preparing a compound of formula (I), wherein: R1 is alkyl, phenylalkyl, phenylalkylphenylmethyl, or optionally substituted naphthylmethyl; R2 is H, halo, alkyl, cycloalkyl, cycloalkenyl, alkoxy, alkylthio, aryl, aryloxy or HET; R4 is -CO2H, -SO3H or -P(O)(OH)2; R5, R6 and R7 are independently H, alkyl, alkoxy, haloalkoxy, haloalkyl, bromo, chloro, fluoro, iodo, or aryl; Also described are the compounds of formula (I) when prepared by this process. Also described is a compound of formula IV, wherein: R1, R2, R5, R6 and R7 are as defined above for the compound of formula (I); The following provisos apply to the compound of formula IV: i) When R5, R6 and R7 are H and R2 is H then R1 is not phenylmethyl. ii) When R5, R6 and R7 are H and R2 is methyl then R1 is not phenylmethyl, (1,1'-biphenyl)-2-ylmethyl, (1,1'-biphenyl)-3-ylmethyl, (1,1'-biphenyl)-4-ylmethyl, 4-fluorophenylmethyl, 2,6-dichlorophenylmethyl, 2-chlorophenylmethyl, 2-methylphenylmethyl, or 1-octyl. iii) When R5, R6 and R7 are H and R2 is ethyl then R1 is not phenylmethyl, (1,1'-biphenyl)-2-ylmethyl, 3-chlorophenylmethyl, or 2-(phenylmethyl)phenylmethyl. iv) When R5, R6 and R7 are H and R2 is 1-propyl then R1 is not (1,1'-biphenyl)-2-ylmethyl. v) When R5, R6 and R7 are H and R2 is cyclopropyl then R1 is not phenylmethyl or (1,1'-biphenyl)-2-ylmethyl.