X-ray structural investigation of gossypol and its derivatives. IX. Semiclathrates of gossypol with esters of acetic acid

Inclusion compounds of gossypol with a number of acetic acid esters have been obtained and have been identified by derivatography and NMR spectroscopy. An x-ray structural investigation of the structures of crystalline complexes of gossypol with ethyl acetate and butyl acetate has shown that these complexes are isostructural semiclathrates. On the basis of the structures of these two semiclathrates of gossypol, it has been concluded that esters and ketone with chain lengths of from five to seven atoms form inclusion compounds isomorphous with the semiclathrates of ethyl and butyl acetates. If the chain length is shorter or longer than that given, inclusion compounds with a different crystal structure are formed.