A Simple Synthesis of 3-Substituted 1-Amino-2-thioxo-4-imidazolidinones, Isolation of the Intermediates, N-Amino-N-ethoxycarbonylmethyl-N'-aralkyl-thioureas

1-Aminothiohydantoin derivatives were prepared in good yields by the reaction of alkyl or arylisothiocyanates with ethyl hydrazinoacetate hydrochloride in presence of triethylamine. The intermediates, N-amino-N-ethoxycarbonylmethyl-N'-aralkylthioure as, which were formed during the reaction and could be transformed into the appropriate 1-aminothiohydantoins, were isolated and characterized.