Methyl-substituted tetrahydro-2-pyrimidinone derivatives of the general formula ##STR1## in which each Ar, independently of each other, represents an aryl group which is optionally mono- or poly-substituted by substituent(s) selected from halogen, C.sub.1 to C.sub.6 alkyl, C.sub.1 to C.sub.6 alkoxy, C.sub.1 to C.sub.6 alkylthio, nitro, phenoxy and trifluoromethyl, and R.sup.1, R.sup.2 and R.sup.3 independently represent a hydrogen atom or a methyl group, provided that at least one of R.sup.1, R.sup.2 and R.sup.3 represents a methyl group, are new and find use as herbicides, in particular as selective herbicides which may be used on weeds in crops such as cotton and rice. The N,N'-diaryl-N-haloalkyl-ureas which are starting materials for the production of compounds of formula (I) are also new.
通式为##STR1##的甲基取代的四氢-2-
嘧啶酮衍
生物,其中每个Ar,独立地表示一个芳基,该芳基可选择地被来自卤素,C.sub.1至C.sub.6烷基,C.sub.1至C.sub.6氧烷基,C.sub.1至C.sub.6烷
硫基,硝基,苯氧基和三
氟甲基的取代基单独或多个取代,而R.sup.1,R.sup.2和R.sup.3独立地表示氢原子或甲基基团,前提是至少R.sup.1,R.sup.2和R.sup.3中的一个表示甲基基团,这些衍
生物是新的,并可用作
除草剂,特别是作为可选择性
除草剂,可用于棉花和稻作物中的杂草。N,N'-二芳基-N-卤代烷基
脲是制备通式(I)化合物的起始材料,也是新的。