Described herein are novel compounds having antineoplastic and antimicrobial activity, obtained via structural modifications of resveratrol and combretastatin A-4, methods for synthesis of these compounds, and their use in pharmaceutical composition and for use in the treatment of mammals having cancer. Examples of the novel compounds are: (Z)- and (E)-3,4',5-trimethoxystilbene (4a, 4b); (Z)- and (E)-3,5-dimethoxy-4'-hydroxystilbene (14c, 14d); (Z)- and (E)-3-hydroxy-4',5-dimethoxystilbene (14g, 14h); (Z)- and (E)-3,5-dihydroxy-4'-methoxy-stilbene (14k, 14l); sodium resverastatin dibenzyl phosphate ((Z)-3,5-dimethoxy-4-[O-bis(benzyl)phosphoryl]-stilbene) (14m); and sodium resverastatin phosphate (14n).