The present invention provides a process of preparing a compound of the formula IV wherein: R1 and R2 are each individually -(C1-C6)alkyl, -(C1-C6)alkoxy or phenyl, R3 is H or -(C1-C6)alkyl, R6 is —NR7R8, morpholin-1-yl, imidazol-1-yl, 4,5-dihydro-1H-imidazol-2-yl, thiomorpholin-1-yl, piperazin-1-yl or piperazin-1-yl substituted with -(C1-C4)alkyl or  and R7 and R8 are each individually hydrogen, -(C1-C6)alkyl, —(CH2)pOH,  —(CH2)p-piperidyl, —(CH2)pS(C1-C6)alkyl, —(CH2)pO(C1-C6)alkyl  where R9 is (C1-C6)alkyl; P is an integer from 1-3 both inclusive; q is 0 or 1; and t is 1 to 6 both inclusive; or a pharmaceutically acceptable salt, hydrate or optical isomer thereof, which is useful as a neuroprotective agent.