摘要:
A high yielding cyclisation of the readily available N-(4,4-diethoxybutyl)-2-(3,4-dimethoxyphenyl)acetamide to 8,9-bis(methyloxy)-2,3,6, 10b-tetrahydropyrrolo[2, I-a]isoquinolin-5(1H)-one is described. The latter can be reduced with either AlH3 or BH3 to (+/-)-crispine A in an overall yield of 55%. (c) 2006 Elsevier Ltd. All fights reserved.