title: (+)-Gibberellin C: hydrogen-bonding pattern of the monohydrate of a non-racemic pentacyclic diterpenoid.
abstract: In the monohydrate of the title compound, (+)-2beta, 4aalpha-dihydroxy-1,7-dimethyl-8-oxo-4bbeta,7alpha- gibbane-1alpha, 10beta-dicarboxylic acid-1,4a-lactone, C(19)H(24)O(6).H(2)O, intermolecular hydrogen bonding progresses helically along b from carboxyl to ketone [O...O = 2.694 (5) A]. The carboxyl and lactone carbonyl groups in translationally related molecules within a helix both accept hydrogen bonds from the same water of hydration. The oxygen of this water in turn accepts a hydrogen bond from the hydroxyl group of a third screw-related molecule in an adjacent counterdirectionally oriented helix, yielding a complex three-dimensional hydrogen-bonding array. Intermolecular O...H-C close contacts were found to the carboxyl and lactone carbonyls, the hydroxyl, and the water.
authors: Carl A. Olson Memorial Laboratories, Department of Chemistry, Rutgers University, Newark, NJ 07102, USA.
authors: H W
authors: HW
authors: Thompson
authors: A P
authors: AP
authors: Brunskill
authors: R A
authors: RA
authors: Lalancette
mesh_terms: D018360:Crystallography, X-Ray; D004224:Diterpenes / Q000737:chemistry*; D005875:Gibberellins / Q000737:chemistry*; D006860:Hydrogen Bonding; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D004224:Diterpenes; D005875:Gibberellins; C420710:gibberellin C