Amaryllidaceae alkaloids. Part I. The crystal structure of dihydrolycorine hydrobromide

Abstract

The structure of dihydrolycorine hydrobromide C₁₆H₁₉O₄N,HBr, has been determined by the three-dimensional X-ray diffraction method. The unit cell is orthorhombic, space-group P2₁2₁2₁, four molecules per unit cell, and a= 13·20, b= 10·90, c= 10·90 Å. The atomic co-ordinates were determined by Fourier and least-squares methods. The final value of R over 1118 independent reflexions was 8·5%. The absolute configuration was determined by the anomalous dispersion method.