1962 年 82 巻 11 号 p. 1515-1520
Derivation of dihydromethylsinomeninol-A (XIV) and dihydromethylsinomeninol-B (XVI) to their respective tosylates (XXIV and XXVII), and their treatment with 2, 4, 6-collidine afforded (-)-3, 4, 7-trimethoxy-N-methyl-Δ6-D-morphinan (XXVI) from (XXVII) and (XXVI) was proved by its hydrolysis (+)-7-oxo-3, 4-dimethoxy-N-methyl-D-morphinan (XXVIII) by treatment with dilute acid. (XXIV) failed to form the enol ether by treatment with collidine. These experimental evidences suggest that the methoxyl at 7-position in (XIV) and (XVI) takes the equatorial configuration (trans to the ethanamine chain at 13-position). It has thereby been clarified that, in the catalytic reduction of sinomenine derivatives, hydrogen adds stereospecifically from the less hindered side i.e. from the direction cis to the ethanamine chain at 13-position.