Urea derivatives of the formula ##STR1## (wherein Ar represents a residue of 5- or 6-membered heteroaromatic ring; R represents a hydrogen atom or a C.sub.1 -C.sub.6 alkyl group; R.sup.1 represents a C.sub.1 -C.sub.6 alkyl group; and R.sup.2 represents a C.sub.1 -C.sub.6 alkyl, C.sub.2 -C.sub.6 alkenyl, or C.sub.1 -C.sub.6 alkoxy group) are produced by reacting an amine of the formula Ar--NH--R (wherein Ar and R have the significance given above) with a carbamoyl halogenide of the formula ##STR2## (wherein X represents a halogen atom, and R.sup.1 and R.sup.2 have the significance given above) in the presence of a Lewis acid in an inert solvent.
根据上述描述,通过在惰性溶剂中在
路易斯酸存在下,将式Ar--NH--R(其中Ar和R具有上述所述意义)的胺与式##STR2##(其中X代表卤素原子,R.sup.1和R.sup.2具有上述所述意义)的
氨基甲
酰卤化物反应,可以制备式##STR1##的
尿素衍
生物。