(+/-)-2-Imidazol-1-ylsuccinic esters were synthesized by thermal addition of imidazole to either fumaric or maleic esters. Acceleration of the reaction was achieved, in some cases, using microwave heating. These esters underwent an easy regioselective hydrolysis, under neutral conditions, to give the corresponding half-esters: (+/-)-3-(alkoxycarbonyl)-2-imidazol-1-ylpropionic acids, through either BAC(3) or BAL(1) mechanisms. Kinetic studies in H2O and D2O as well as O-18 and O-17 labeling experiments supported the proposed mechanism. The results of these hydrolyses, which depended on the nature of the alcohol moiety, were compared with those obtained with some imidazol-1-ylacetate analogues or with (+/-)-2-pyrazol-1-yl- and benzimidazol-1-ylsuccinic esters. In general, imidazolylsuccinic esters hydrolyzed faster than the homologous derivatives from pyrazole or benzimidazole.
Polymorphism of racemic imidazol-1yl succinic acid derivatives. Suitable probes for extracellular pH by magnetic resonance spectroscopic imaging (MRSI).
作者:Paloma Ballesteros、Carmen Ubide-Barreda、Mª Luisa Rojas、Pedro José Martínez de Paz、Valeria Righi
DOI:10.3998/ark.5550190.0012.314
日期:——
The polymorphism of racemic imidazol-1ylsuccinic acidderivatives, a series of compounds previously used as extracellularpHprobes for NMR spectroscopy, is investigated by crystallization in different solvents. The mono-ester, (±)-3-(ethoxycarbonyl)-2-(imidazol-1-yl) propionic acid, shows two different polymorphs when recrystallized in absolute ethanol (Form I) or water (Form II), respectively. These
通过在不同溶剂中结晶来研究外消旋咪唑-1基琥珀酸衍生物的多态性,这是一系列以前用作核磁共振光谱的细胞外 pH 探针的化合物。单酯,(±)-3-(乙氧基羰基)-2-(咪唑-1-基)丙酸,分别在无水乙醇(I型)或水(II型)中重结晶时显示两种不同的多晶型物。这两种形式已通过光学显微镜、粉末 X 射线衍射分析和热重分析进行表征。多晶型物 I 和 II 也可以通过固态 CP-MAS C NMR 光谱进行区分。
MROCZKIEWICZ, A., ACTA POL. PHARM., 1984, 41, N 4, 435-440