X-RAY STRUCTURAL INVESTIGATION OF GOSSYPOL AND ITS DERIVATIVES XXIX. MOLECULAR AND CRYSTAL STRUCTURE OF A COMPLEX OF GOSSYPOLIC ACID LACTONE WITH ACETIC ACID

The lactone of gossypolic acid, obtained by the demethylation of the tetramethyl ether of gossypolic acid, forms with acetic acid a stable complex having the 1∶4 composition. The crystallographic parameters of single crystals are as follows:a=20.251(2) A, b=12.028(3) A, c=15.934(4) A, V=3881.2(2.3) A3,Z=4, Dcalc=1.32 g/cm3, sp. gr. Pbcn. The molecule is characterized by considerable strain because of the formation of the five-membered lactone ring the atoms of which are coplanar with the atoms of the naphthyl fragment. Unlike the clathrates of racemic gossypol and dianilinegossypol, the gossypolic acid lactone — acetic acid comples does not belong to the type of clathrate inclusion compounds.