| 摘要 |
<p>1,3 - Dimethyl - 3 - (2 - benzothiazolyl) thiourea is obtained by reacting 2-(methylamino)-benzothiazole in an inert solvent with methyl thiocyanate, whereby tertiary bases, e.g. pyridine, may be added as catalysts. 1,1 - Dimethyl - 3 - (2 - benzothiazolyl) thiourea is obtained by reacting N,N-dimethylthiocarbamic acid chloride with 2-aminobenzthiazole in the presence of a solvent, e.g. pyridine, at about - 10 DEG to +20 DEG C.ALSO:Herbicidal compositions comprise as active ingredient a substituted thiourea of formula: <FORM:1028929/A5-A6/1> wherein R1 and R2, which may be the same or different, are each a hydrogen atom or a methyl or ethyl radical, in admixture with a solid diluent or carrier, or in admixture with an organic solvent and an emulsifying agent capable of producing a stable emulsion when diluted with water, or in admixture with water containing an auxiliary solvent and/or an emulsifying agent. The compositions may be applied in the form of emulsifiable concentrates, spray powders, pastes, soluble powders, dusts and granulates. Non-ionic and anionic emulsifiers are specified.</p> |
