Synthesis, tautomeric forms, specific intermolecular interactions, and lipophilicity of methylated 6-hydroxypyridazine-3-carboxylic acid and its 4,5-dihydro analogs
作者:Anna Katrusiak、Paweł Piechowiak、Andrzej Katrusiak
DOI:10.1016/j.molstruc.2011.05.016
日期:2011.7
derivatives. Carboxylic acid 2 preferably crystallizes as a hydrate, built of carboxylate anions and hydronium cations 2− H3O+, hydrogen bonded into catemeric patterns involving both ions. In methyl 4,5-dihydro-6-oxopyridazine-3-carboxylate (4A) the molecules are NH⋯O hydrogen bonded into chains. In both structures 2− H3O+ and 4A, there are relatively strong CH⋯O hydrogen bonds, arranging the molecules
摘要 已经研究了一系列甲基化 4,5-二氢-6-羟基哒嗪-3-羧酸和 6-羟基哒嗪-3-羧酸(1 和 2)的甲基化对分子间相互作用和亲脂性的影响。在溶液中,它们以内酰胺和内酰胺互变异构体的平衡状态存在,类似物 1 和 2 的相反偏好会影响其甲基化衍生物的合成。羧酸 2 优选以水合物的形式结晶,由羧酸根阴离子和水合氢阳离子 2- H3O+ 构成,氢键结合成涉及这两种离子的分子式模式。在 4,5-dihydro-6-oxopyridazine-3-carboxylate (4A) 中,分子由 NH⋯O 氢键连接成链。在 2− H3O+ 和 4A 两种结构中,都有相对较强的 CH⋯O 氢键,将分子排列成片状。