A large number of 2- (phenylpiperazinoalkoxyphenyl) thiazolidine-3-thiocarboxamides and the corresponding carboxamides (II) were synthesized and tested for inotropic activity in anesthetized dogs. Compounds II were prepared from a hydroxybenzaldehyde (III) through the intermediates (IV, V, and X). Structure-activity relationships (SAR) were investigated by varying the structural parameters. Transposition of the piperazinoalkoxyl group to the meta or para position from the ortho position caused a marked fall in activity. Conversion of the thiocarboxamido to a carboxamido group caused a marked increase in activity. This tendency was generally observed in this series of compounds and constitutes a major deviation from the SAR in the simple 2-phenylthiazolidine series. With regard to effects of the length of the aminoalkoxy chain, the ethoxy derivatives were generally more potent than higher analogues. Lengthening of the N-alkyl group in the (thio) carboxamido group generally caused a decrease in activity. Among the various derivatives synthesized, II15 was found to be approximately one hundred times more potent than amrinone with a long duration of action.
大量2-(苯基
哌嗪基烷氧苯基)
噻唑烷-3-
硫代羧酰胺及其相应羧酰胺(II)被合成并在麻醉犬中测试其强心活性。化合物II通过羟基
苯甲醛(III)及其中间体(IV、V和X)制备。通过改变结构参数来研究结构-活性关系(
SAR)。将
哌嗪基烷氧基团从邻位位置移至间位或对位导致活性显著下降。将
硫代羧酰胺转变为羧酰胺基团导致活性显著增加。这种趋势在这一系列化合物中普遍存在,并构成与简单
2-苯基噻唑烷系列
SAR的主要偏离。关于
氨基烷氧链长度的影响,乙氧基衍
生物通常比更高级的类似物更有效。在(
硫代)羧酰胺基团中延长N-烷基通常导致活性下降。在合成的各种衍
生物中,II15被发现其效力约为
氨力农的一百倍,且作用时间较长。