| abstract |
Process for the preparation of 2-oxa-olylurea derivatives of the general formula I: (wherein R 1 represents a hydrogen atom or a C 1 -C 3 alkyl or phenyl group, R 2 represents a hydrogen, methyl, hydroxymethyl or acetoxymethyl, R3 represents a n-butyl, amyl, benzyl, cyclohexyl, cyclohexylmethyl or styryl group, and cyclohexylmethyl R4 represents a C1-6 alkyl, cyclohexyl, 2- chloro, phenyl, o-, m-p-chlorophenyl, trifluoromethyl or allyl, characterized in that an oxazole derivative of the general formula II (wherein R 1, R 2 and R 3 are as defined above) , with an isocyanate of the general formula III: wherein R4 has the above meaning, the reaction being carried out in anhydrous benzene at reflux. |