The synthesis of some derivatives of 4,5,6,6a,7,12-hexahydroisoquinolino [8,l -ab]carbazole

As part of a general project on the chemistry of alkaloid analogues, the synthesis of derivatives 5, of 4,5,6,6a,7,12-hexahydroisoquinolino[8,l-ab]carbazole, which can be considered as ring D indole analogues of the aporphine skeleton, was investigated. Compounds of this type are of interest on two grounds. Firstly it is conceivable some may occur naturally; and secondly, they may display unusual pharmacological properties, since the side-chain configuration of the tryptophan residue is intermediate between that present in lysergic acid diethylamide and the yohimbine-reserpine type alkaloids.