Chapter 20 Phthalideisoquinoline Alkaloids

Abstract

This chapter discusses studies that focus on phthalideisoquinoline alkaloids. The reactions of narcotine with ethyl chloroformate, with benzyl iodide and alkali, and with alkyl magnesium bromides are interpretable in terms of its structure. Some N -demethylation was noted when narcotine reacted with N -2,4,6-tetrachlorbenzanilide. The lactone group of narcotine is readily reduced by lithium aluminum hydride in ether solution but not in the presence of pyridine. The resulting diol was considered to be identical with the tetrahydronarcotine of Finzi and Freund obtained by electrolytic reduction. Hydrolytic fission of narcotoline proceeds analogously to that of narcotine yielding meconine and cotarnoline ( O -desmethylcotarnine). The synthesis of dl -corlumine and its resolution have been reported. Amino-x-adlumine was deaminated either directly by diazotization and reduction with hypophosphorous acid, or by conversion to dl -iodocorlumine followed by reduction in the presence of Raney nickel. The racemic compound was resolvable by means of the tartaric acids and both optical antipodes were obtained. Because no alkaloid having the adlumine configuration was obtained, it is recognized that the condensation of lodal with the nitrophthalide is stereospecific.