NICOTINIC ACID DERIVATIVES AND HERBICIDES

摘要

A nicotinic acid derivative represented by general formula (I) or (II), a salt thereof, and a herbicide containing the same as the active ingredient, wherein A represents substituted phenyl, or 5- or 6- membered heterocycle, e.g., thienyl or pyridyl; R represents hydroxy, optionally substituted alkoxy or optionally substituted benzyloxy; R1 and R2 represent each independently alkoxy or halogen; R3 and R4 represent each independently hydrogen, hydroxy, cyano or alkoxycarbonyl, or they may be combined together to represent oxygen; X represents halogen, alkyl or alkoxy; n represents 0, 1 or 2; and Z represents methine or nitrogen. The compound and salts thereof can control annual or perennial weed growing on the land where various crops such as rice plant, wheat, cotton and corn grow for a wide period ranging from the preemergence to growth in a remarkably small dose.