Abstract
Based on the fundamental experiments carried out on simple dibenzo-p-dioxin derivatives, fission reaction with metallic sodium in liquid ammonia was applied to isotrilobine and this base was successfully cleaved into two coclaurine moieties constituting this molecule. Two-step cleavage reaction with metallic sodium in liquid ammonia afforded only one kind of non-phenolic base, S (+)-1-(p-methoxybenzyl)-2-methyl-6-methoxy-1, 2, 3, 4-tetrahydroisoquinoline (XIa). The phenolic base was methylated and afforded S (+)-N, O, O-trimethylcoclaurine (XIV) and (+)-1-(p-methoxybenzyl)-2-methyl-6, 8-dimethoxy-1, 2, 3, 4-tetrahydroisoquinoline (VIII). These experimenal results revealed that isotrilobine is indicated by the structural formula (XV) in which the absolute configuration of the asymmetric centers is both in S configuration.
