Abstract
Alkaloids of sinomenine type (OH in 4, H in 1) are linked together in 1, 1'-position by mild oxidation. Here is formed always a pair of isomerides, one of which belongs to the normal series and the other to the pseudo series. The series relation was determined. The authors assume the cause of the existence of the pair in the hindrance of free rotation of the linked molecules by the ethanamine chain. By Hofmann decomposition to the thebenone stage, both the normal and pseudo derivatives gave the same des-N-methyl-bases and thebenones. The ultra-violet absorption curves also showed the difference of normal and pseudo isomerides, but the identity of the des-N-methyl-bases and the thebenones from the both sources.
