Two crystal polymorphs of a flavonoid from Melicope ellyrana

The crystal structure determinations of two crystalline components of the hexane extract of the fruit of the indigenous Australian tree Melicope ellyrana have shown them to be polymorphs of the same compound, namely the flavonoid 4′,5-di­hydroxy-3,3′,8-tri­methoxy-7-(3-methyl­but-2-enyl­oxy)­flavone systematic name: 5-hydroxy-2-(4-hydroxy-3-methoxy­phenyl)-3,8-di­methoxy-7-(3-methyl­but-2-enyl­oxy)-4H-1-benzo­pyran-4-one], C₂₃H₂₄O₈. The two polymorphs, one monoclinic (polymorph A) and the other triclinic (polymorph B), show significant conformational differences, particularly in the enyl­oxy side chain, while only one (polymorph A) shows intermolecular hydrogen bonding.