◊ These authors contributed equally to this work.
Abstract
A novel synthesis of the tetrahydroisoquinoline alkaloid jamtine and its epimer is reported. The synthetic strategy hinges on a one-pot conjugate reduction/Robinson cyclization sequence and an efficient benzyl configuration inversion by an oxidation/reduction approach. The N -oxide derivatives of the jamtine isomers were also synthesized and identified by X-ray crystallographic analysis. Additionally, a density functional theory calculation for the four possible N -oxide structures was exploited to gain further insight into the structure of the natural product in comparison to those of the synthetic N -oxides, because the NMR data of the synthetic derivatives did not match those reported for natural jamtine N -oxide.
Key words natural products - jamtine - total synthesis - one-pot reaction - conjugate reduction - Robinson cyclization
