NICOTINIC ACID DERIVATIVES AND HERBICIDES

摘要

A nicotinic acid derivative represented by the general formula <IMG> or <IMG> [wherein A a substituted phenyl group or a 5- or 6- membered hererocyclic ring (e.g., a thienyl group or a pyridyl group), R is a hydroxyl group, an optionally substituted alkoxy group or an optionally substituted benzyloxy group, each of R1 and R2 which may be the same or different, is an alkoxy group or a halogen atom, each of R3 and R4 which may be the same or different, is a hydrogen atom, a hydroxyl group, a cyano group or an alkoxycarbonyl group, or R3 and R4 may together represent an oxygen atom, X is a halogen atom, an alkyl group or an alkoxy group, n is 0 or an integer of from 1 to 2, and Z is a methine group or a nitrogen atom] or a salt thereof, and a herbicide containing it as an active ingredient. The compound and salts thereof can control annual and/or perennial weeds growing on the land where various -72- crops such as rice, wheat, cotton and corn grow over a broad period from the pre-emergence season to the growing season in a remarkably small dose.