Asymmetric Synthesis of 3-Oxa-15-deoxy-16-(m-tolyl)-17,18,19,20-tetranorisocarbacyclin and Its Neuroprotective Analogue 15-Deoxy-16-(m-tolyl)-17,18,19,20-tetranorisocarbacyclin Based on the Conjugate Addition–Azoalkene–Asymmetric Olefination Strategy
作者:Marc van de Sande、Hans-Joachim Gais
DOI:10.1002/chem.200600728
日期:2007.2.12
and 7 b are based on the convergent conjugate addition-azoalkene-asymmetric olefination strategy. Key building blocks are the readily available bicyclic azoalkene 14 and the alkenylcopper derivative 15. The stereoselective conjugate addition of 15 to 14 gave hydrazone 13, which was stereoselectively converted to the bicyclic ketone 11. The key steps for the construction of the alpha side chain of 7
完全立体控制的3-oxa-15-deoxy-16-(间甲苯基)-17,18,19,20-四正异卡巴环素的合成(3-oxa-15-deoxy-TIC,7 b)和15的正式形式描述了-脱氧-16-(间甲苯基)-17、18、19、20-四正异卡巴环素(15-脱氧-TIC,7a)。15-脱氧-TIC对神经元前列环素受体(IP2)具有特异性,并具有神经保护活性,新的3-oxa-15-脱氧-TIC预期在代谢上比15-脱氧-TIC更稳定。7a和7b的合成基于收敛的共轭加成-偶氮烯烃-不对称烯烃化策略。关键的组成部分是易于获得的双环偶氮烯烃14和烯基铜衍生物15。立体选择性共轭加成15至14得到了13,13,其被立体选择性地转化为双环酮11。构建7a和7b的α侧链以及区域选择性引入内环Delta6,6a双键的关键步骤是:1)用手性Horner-Wadsworth-Emmons试剂对酮11进行高度选择性的不