Ethyl esters of 4-substituted piperazinoacetic acids IIIa-f were prepared by alkylation of 1-(ethoxycarbonylmethyl)piperazine with 2-methoxyethyl bromide, 2-ethoxyethyl bromide, 2-methylthioethyl chloride, 2-phenoxyethyl bromide and 2-phenylthioethyl bromide or by reactions of 1-(3-methoxypropyl)piperazine and 1-(2-methylthioethyl)piperazine with ethyl chloroacetate. Reactions of the esters with hydrazine hydrate gave the hydrazides IVa-f. Their treatment with 7-chloro-5-(2-chlorophenyl)-1,3-dihydro-1,4-benzodiazepin-2-thione resulted in the title compound Ia and analogues Ib-f. 1-(4-Methylpiperazinomethyl) derivatives Ig and IIg were similarly prepared from 4-methylpiperazinoacetic acid hydrazide (IVg). Compound Ig showed significant central depressant and anticonvulsant (electroshock) activity in mice. The enlargement of the substituent in position 4 of the piperazine residue results in an important decrease of these activities.
4-取代
哌嗪基
乙酸乙酯IIIa-f通过将1-(乙氧羰基甲基)
哌嗪与2-甲氧基乙基
溴、
2-乙氧基乙基溴、2-甲
硫基乙基
氯化物、2-苯氧基乙基
溴和2-苯
硫基乙基
溴进行烷基化反应制备,或者通过
1-(3-甲氧基丙基)哌嗪和
1-(2-甲硫基乙基)哌嗪与
氯乙酸乙酯反应制备。这些酯与
水合
肼反应得到
肼酰
肼IVa-f。它们与7-
氯-5-(2-
氯苯基)-1,3-二氢-1,4-苯并二氮杂
硫蒽-2-
硫酮反应得到标题化合物Ia及类似物Ib-f。1-(4-甲基
哌嗪基)衍
生物Ig和IIg类似地由4-甲基
哌嗪基
乙酸肼IVg制备而成。化合物Ig在小鼠中显示出显著的中枢抑制和抗惊厥(电休克)活性。在
哌嗪残基的4位上增大取代基会导致这些活性的显著减少。