Formation of compounds with antigonadotropic activity from inactive phenolic precursors

The antigonadotropic activity of Lithospermum and Lycopus species can be attributed to their phenolic components. These compounds represent precursors of biologically active products which are formed by an oxidation step. Complexity and instability of these products aggravates the elucidation of detailed structural properties. Therefore, the type of reaction involved had to be clarified. Among the oxidation products of phenolic substances, the corresponding quinones are found. It can be demonstrated that the reaction between quinones and unoxidized diphenols yields products with strong antigonadotropic activity. This type of reaction - the formation of quinhydrones - is proposed to be engaged in the formation of various products with antigonadotropic activity.