摘要 |
Ureas (I; X=C1-2 alkyl, C1-2 alkoxy, (C1-2)-alkoxycarbonyl, aminocarbonyl, (C1-4) alkylamino; Me2N, Et2N or MeEtN or their Noxides, MeS, EtS, MeSO2 n EtSO2; or PhS or PhSO2 (both opt. ring substd. by 1-5 halogen); Y=H, C1-2 alkyl or trihalomethyl; m=1; n=0 or 1) were prepd. by the oxidation of N-phenyl-N'-(pyridinyl)urea (II). (I) are plantgrowth regulators, esp. for appln. to broadleaf and grain crops such as soybean and wheat crops; they retard senescence, with an increase in crop yield. |