The action of amines on citraconic anhydride. X-Ray crystal structure of (Z)-2-methyl-3-pyrrolidinocarbonylpropenoic acid
作者:Ahmet E. Baydar、Gerhard V. Boyd、John Aupers、Peter F. Lindley
DOI:10.1039/p19810002890
日期:——
The reaction of citraconic anydride with 15 primary and secondary amines gave mixtures of isomeric citraconamic acids (2) and (3), in which the former predominated. The more abundant isomers rearranged to the thermodynamically stable N-substituted (Z)-2-methyl-3-carbamoylpropenic acids (3) on warming. The structure of the pyrrolidide (3q) was confirmed by X-ray analysis. An unsuccessful attempt to
Comparison of pH-sensitive degradability of maleic acid amide derivatives
作者:Sunyoung Kang、Youngeun Kim、Youngjun Song、Jin Uk Choi、Euddeum Park、Wonmin Choi、Jeongseon Park、Yan Lee
DOI:10.1016/j.bmcl.2014.03.057
日期:2014.5
We synthesized five maleic acid amide derivatives (maleic, citraconic, cis-aconitic, 2-(2'-carboxyethyl) maleic, 1-methyl-2-(2'-carboxyethyl) maleic acid amide), and compared their degradability for the future development of pH-sensitive biomaterials with tailored kinetics of the release of drugs, the change of charge density, and the degradation of scaffolds. The degradation kinetics was highly dependent upon the substituents on the cis-double bond. Among the maleic acid amide derivatives, 2-(2'-carboxyethyl) maleic acid amide with one carboxyethyl and one hydrogen substituent showed appropriate degradability at weakly acidic pH, and the additional carboxyl group can be used as a pH-sensitive linker. (C) 2014 Elsevier Ltd. All rights reserved.