| 摘要 |
<p>Pyridine sulfonylureas of the formula: <CHEM> wherein W is O or S; R is H or CH3; R1 is H, halogen, CN, or a lower aliphatic substituent; R2 is H, CN, OH, NH2 or an organic substituent; R3 is H, alkyl or haloalkyl; R4 is H, F, Cl or CH3; A is a mono- or bicyclic heterocyclic group, especially pyrimidin-2-yl or 1,3,5-triazin-2-yl; and their agriculturally suitable salts, exhibit potent herbicidal activity. Some may also be used as plant growth regulants. The compounds may be made e.g. by reacting an an appropriate pyridine sulfonamide with the appropriate phenyl carbamate or thiocarbamate of formula <CHEM> y</p> |
