A number of thalidomide metabolites having superior anti-angiogenic properties have now been isolated and identified. In addition, thalidomide analogs that mimic the effects of the isolated and identified active thalidomide metabolites, and variations of such thalidomide analogs, have been developed. Such thalidomide analog compounds show enhanced potency in the inhibition of undesirable angiogenesis without the undesirable effects of administration of thalidomide.