The Synthesis of Some Pyrimidinyl and Thiazolyl Ureas and Thioureas and Some Related Compounds

Some pyrimidin-2- and pyrimidin-4-amines were treated with isocyanates and isothiocyanates to give the corresponding disubstituted ureas or thioureas . A pyrimidin-2-amine is more reactive than a pyrimidin-4- amine in these reactions. 2-Aminothiazoles and thiazolinones also react to give the disubstituted ureas or thioureas . The use of ethoxycarbonyl or benzoyl isothiocyanate or isocyanate gives products which are readily hydrolysed to the pyrimidinyl or thiazolyureas or thioureas but with concomitant hydrolysis and decarboxylation of an ethoxycarbonyl substituent . The use of chlorosulfonyl or trimethylsilyl isocyanate gives the urea derivative without isolation of the intermediate disubstituted urea. Some related compounds were also synthesized.