Structure-activity relationships in the trans-hexahydroindolo[4,3-ab]phenanthridine ("benzergoline") series. 2. Resolution, absolute configuration, and dopaminergic activity of the selective D1 agonist CY 208-243 and its implication for an "extended rotamer-based dopamine receptor model"
作者:Max P. Seiler、Philipp Floersheim、Rudolf Markstein、Armin Widmer
DOI:10.1021/jm00060a004
日期:1993.4
group. In order to determine the enantioselectivity of the 7-methyl derivative in the adenylate cyclase assay, its 5,5a-dihydro precursor was resolved and both enantiomers oxidized to the final products. The biological activity was found to reside entirely in the (-)-enantiomer, (-)-1 (CY 208-243). An X-ray study of its (-)-mandelic acid salt revealed a 6aR,12bR absolute configuration, which, in confirmation
4,6,6a,7,8,12b-六氢吲哚并[4,3-ab]菲啶(“苯并五氢萘”)是缺乏邻苯二酚基团的强力和选择性多巴胺D1激动剂的第一类结构。为了在腺苷酸环化酶测定中确定7-甲基衍生物的对映选择性,将其5,5a-二氢前体拆分,并将两种对映异构体氧化成最终产物。发现生物活性完全存在于(-)-对映异构体(-)-1(CY 208-243)中。对其(-)-扁桃酸盐的X射线研究显示其6aR,12bR绝对构型,在确认结构假设的情况下,与麦角灵相对应。出乎意料的是,在晶体结构中观察到了N-甲基的轴向构象。相反,随后分析的(-)-1游离碱晶体揭示了N-甲基的赤道构象,我们认为它代表了生物活性构象。基于确定的绝对构型,(-)-1可以在先前描述的“基于旋转异构体的多巴胺受体模型”中定位,该模型可以定位“亚型选择性诱导位点”(D1受体处的芳基结合位点, D2受体的空间障碍),以苯并麦角林分子的构象固定的“附加”苯基标记。