Relation of Vomicine to Strychnine and Brucine

Abstract

VOMICINE, C₂₂H₂₄O₄N₂, a congener of strychnine, C₂₁H₂₂O₂N₂, has been investigated by Wieland and his collaborators ; but no precise connexion between the alkaloids has yet been disclosed, though many reactions and transformations suggest the close similarity of their molecular structure. On oxidation with chromic acid¹, vomicine yields an acid, C₁₇H₂₂O₅N₂, 3H₂O, which characteristically loses carbon dioxide at 130°, affording a base, C₁₆H₂₂O₂N₂. We have now found that the same acid can be obtained by oxidation of N-methyl-sec-pseudo-strychnine, or better, H-methyl-sec-pseudobrucine, by means of chromic acid. The identity has not yet been confirmed by direct comparison^* ; but there can be little doubt of it from the analyses (3H₂O), rotatory power, melting points, and behaviour on heating. The resulting base has the composition, melting point and crystalline form recorded for the product from vomicine.