Preparation and Oxidation Chemistry of the Catechol Estrogens: Relevance to Estrogen-Related Carcinogenesis and Potential for Drug Design

In this review we will briefly survey the oxidation chemistry of the catechol estrogens (2-hydroxy- and 4- hydroxyestradiol, 2-OH-E and 4-OH-E) as a result of the research carried out in the authors' laboratory and other centers during the past decade. The central focus of the paper will be on the main pathways of oxidative modification and their possible relevance to the mechanisms of estrogen-related carcinogenesis. The chemical bases underlying the different reactivity and toxicity of 2-hydroxy and 4-hydroxyestradiol will be addressed. The value of catechol estrogen oxidation in the discovery of novel functionalized or modified steroidal scaffolds of potential pharmaceutical interest will be also briefly highlighted.