INCLUSION COMPLEXES OF THE NATURAL PRODUCT GOSSYPOL - CRYSTAL-STRUCTURE OF THE 1-1 COMPLEX OF GOSSYPOL WITH ISOVALERIC ACID

The crystal structure of the 1 : 1 lattice inclusion complex of gossypol with isovaleric acid has been determined by X-ray structure analysis. The crystals of C30H30O8″″C5H10O2 are monoclinic, space group C2/c, a=28.835(7), b=9.063(2), c=26.880(4)Å, β=109.66(1)°, V=6615(2) Å3, Z=8, Dx = 1.25 g cm-3, μ(Cu Kα) = 7.14 cm-1, T = 295 K. The structure was solved by direct methods and refined with isotropic thermal parameters to the final R value of 0.132 for 1114 observed reflections. Hydrogen bonded gossypol molecules form columns along the [1 0 1] direction. These columns pack into layers parallel to the (101) plane. The layers of gossypol molecules are separated by the layers of isovaleric acid. The acid molecules are connected via a pair of O-H...O hydrogen bonds forming centrosymmetric dimers. There is no hydrogen bond interaction between the carboxylic acid dimers and gossypol molecules. © 1990 Kluwer Academic Publishers.