Herbicidal thiophenesulfonamides and pyridinesulfonamides.

摘要

Sulfonylurea derivatives of formula <CHEM> wherein B is a substituted thienyl or pyridyl group; W is O or S; R is H or CH3; and A is a mono- or bicyclic heterocyclic group, e.g. pyrimidinyl or triazinyl; and their agriculturally suitable salts, exhibit potent herbicidal activity. Some also show a plant growth regulant effect. The novel compounds may be formulated into compositions for agricultural use in conventional manner. They may be made by a variety of synthetic routes, e.g. by reacting an appropriate sulfonyl isocyanate or isothiocyanate of formula BNCW with an appropriate heterocyclic amine HNR.A.