The Crystal Structure of Morphine Hydrate.

Abstract

The crystal and molecular structure of the monohydrate of morphine [a narcotic analgesic], was determined by X-ray methods. The compound crystallizes in space group P212121, with a = 7.438(1), b = 13.751(3), c = 14.901(3) .ANG.. The structure was determined by direct methods and refined by full-matrix least-squares methods to an R-value of 0.045 for 1150 observed reflections. The esd''s for non-H atoms are 0.005-0.006 .ANG. and 0.3-0.4.degree. in bond lengths and angles, respectively. The morphine molecule has the usual T-shape with an angle of 8.6.degree. between the 2 planar parts. The water molecule bridges the phenolic and hydroxylic oxygen atoms through two O.sbd.H.cntdot..cntdot..cntdot.O bonds acting as a donor in both. There is an extensive network of H bonds throughout the molecular crystal, including chains of morphine molecules parallel to the b-axis formed by a strong O.sbd.H.cntdot..cntdot..cntdot.N H bond of 2.635 .ANG.. A common structural feature of narcotic analgetics and phenethylamines is discussed.