PROCESS OF PRODUCING A PYRAZINE DERIVATIVE

摘要

OF THE DISCLOSURE A process of producing a pyrazine derivative represented by the formula wherein R1 and R2, which may be the same or different, each represents a hydrogen atom, a halogen atom, a hydroxy group, a lower alkoxy group, a phenyl lower alkoxy group, a phenoxy group, a mercapto group, a lower alkylthio group, a phenyl lower alkylthio group, a phenylthio group, an amino group, a substituted amino group, a lower alkyl group, a carbamoyl group or a sulfamoyl group; R3 represents a lower alkoxy group; R4, R5, and R6, which may be the same of different, each represents a hydrogen atom, a lower alkyl group, a cycloalkyl group, a phenyl lower alkyl group, or a phenyl group; and A represents a lower alkylene group; said R4 and A, said R5 and A, said R4 and R5, or said R5 and R6 may form a 5-membered or 6-membered nitrogen-containing heterocyclic ring which may further contain a hetero-atom together with nitrogen atom and the pharmacologically acceptable non-toxic salts thereof. The compound of this invention has a strong and selective antiemetic activity and an effect of stimulating the gastric motility.