54888-20-9Relevant academic research and scientific papers
Nouvelles syntheses de phenyl-4 allophanates
Al Sabbagh, Mohamed Mowafak,Calmon, Michelle,Calmon, Jean-Pierre
, p. 73 - 77 (2007/10/02)
The synthesis of eighteen alkyl or phenyl 4-phenylallophanates is described.The classical methods used for the preparation of allophanates - namely, condensation between an isocyanate and a carbamate, reaction between a urea and a carbonate, desulphurization of 3-thioallophanic acid esters - proved to be unsuitable for the synthesis of 4-phenylallophanic acid phenyl esters.Variously substituted 4-phenylallophanates can be obtained by reacting a chloroformate with a phenylurea in the presence of pyridine, which promotes the transfer of the carboxylate group.The occurence of electrondonating substituents, such as CH3, at the nitrogen atom receiving the carboxylate group promotes the reaction.The low yields observed for aliphatic esters can be accounted for by the instability of the alkyl chloroformate-pyridine complex.The structures of the derivatives synthesized was corroborated by the analysis of their n.m.r. and u.v. spectra. Non-commercial phenyl chloroformates were prepared by reacting phosgene with a sodium phenolate in the presence of anhydrous benzene.
1-Aziridine carboxylic acid derivatives with immunostimulant activity
-
, (2008/06/13)
2-Substituted-1-aziridine-carboxylic acid esters exhibiting immuno-stimulant activity and of the formula STR1 wherein X is a carbamoyl or alkoxycarbonyl radical, and R1 is an aliphatic hydrocarbon radical optionally substituted by halogen, alkoxy, amino, carbamoyloxy, cycloalkyl, hydroxyl, an imido or heterocyclic radical, cycloalkyl; or aryl, aralkyl, aryloxyalkyl or arylthioalkyl wherein the aryl moiety is optionally substituted by halogen, alkyl, alkoxy, hydroxyl, amino, nitro, cyano, acyl, carbalkoxy, thioalkyl, alkylsulphonyl, phenyl or trifluoromethyl. Counterparts where X is --CN and R1 is as above, except for ethyl, are also new.
