Derivatives and isosteric derivatives of the potent 5-HT1A agonist 8-(di-n-propylamino)-6,7,8,9- tetrahydro-3H-benz[e]indole-1-carbaldehyde (5) were prepared and evaluated in vivo and in vitro for serotonergic and dopaminergic activity. The 1-cyano analog 8 was found to be almost equipotent to 5 and the previously described 2-cyano derivative 6, while a 1-chloro and 1-(1,1,1-trifluoroethyl) substituent (9 and 10, respectively) formed less potent derivatives. The isosteric 6,7,8,9-tetrahydro-1H-benz[g]indoles 4 and 12-15 showed surprisingly low affinity or activity at both serotonergic and dopaminergic systems. The interpretations of these results by means of drug-receptor interactions at the 5-HT1A subtype are discussed. Compounds 6 and 8 were found to have high oral bioavailability in the rat (63% and 54%, respectively).

中文翻译：

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6,7,8,9-四氢-N，N-二正丙基-3H-苯并吲哚-8-胺。衍生物为有效的和口服活性的5-羟色胺5-HT1A受体激动剂。

制备了有效的5-HT1A激动剂8-（二-正丙基氨基）-6,7,8,9-四氢-3H-苯并[e]吲哚-1-甲醛（5）的衍生物和同构衍生物体内和体外具有血清素和多巴胺能活性。发现1-氰基类似物8​​与5和先前描述的2-氰基衍生物6几乎等价，而形成1-氯和1-（1,1,1-三氟乙基）取代基（分别为9和10）。效力较低的衍生物。等规6,7,8,9-四氢-1H-苯并[g]吲哚4和12-15在血清素能系统和多巴胺能系统中均显示出令人惊讶的低亲和力或活性。讨论了通过5-HT1A亚型的药物-受体相互作用对这些结果的解释。发现化合物6和8在大鼠中具有较高的口服生物利用度（分别为63％和54％）。