Crystalline inclusion complexes on the basis of the mixed “gossypol–pyrazine” host

Abstract Crystal engineering of gossypol using pyrazine as a complexing agent led to the discovery of new families of crystalline inclusion complexes on the basis of a mixed “gossypol–pyrazine” host. Depending on the H-bonding ability of the solvent guest molecules, different types of clathrates were formed. In these clathrates, pyrazine molecules incorporate gossypol molecules to relatively robust mixed host matrix through symmetrical H-bonds of the type O–H⋯N.