Pseudopolymorphism in brucine: brucine-water (1/2), the third crystal hydrate of brucine.
The structure of a third pseudopolymorphic hydrate of brucine, brucine-water (1/2) [systematic name: 2,3-dimethoxystrychnidin-10-one-water (1/2)], C(23)H(26)N(2)O(4).2H(2)O, has been determined at 130 K. The asymmetric unit comprises two independent brucine molecules and four water molecules of solvation. The four water molecules form uncommon cyclic hydrogen-bonded homomolecular R(4)(4)(8) tetramer rings, which then form primary hydrogen-bonded chain substructures extending down the 2(1) screw axis in the unit cell. The two brucine molecules are linked peripherally to these substructures by either single O-H...N(brucine) or asymmetric three-centre O-H...O(brucine) hydrogen bonds.
School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia. g.smith@qut.edu.au
Graham
G
Smith
Urs D
UD
Wermuth
Jonathan M
JM
White
D000838:Anions; D018360:Crystallography, X-Ray / Q000379:methods*; D006859:Hydrogen; D006860:Hydrogen Bonding; D007202:Indicators and Reagents / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure; D011522:Protons; D013331:Strychnine / Q000031:analogs & derivatives* / Q000737:chemistry; D013696:Temperature; D014867:Water / Q000737:chemistry*
D000838:Anions; D007202:Indicators and Reagents; D011522:Protons; D014867:Water; C083806:brucine; D006859:Hydrogen; D013331:Strychnine