Using a newly developed strategy whose key step is the regioselective propargylation of hydroxyxanthone substrates, 99 structurally diverse Garcinia natural-product-like xanthones based on gambogic acid were designed and synthesized and their in vitro antitumor activity was evaluated. A set of 40 related compounds was chosen for determination of their physicochemical properties including polar surface area, log D-7.4, aqueous solubility, and permeability at pH 7.4. In the light of the in vitro antitumor activity and the physicochemical properties, two compounds were advanced into in vivo efficacy experiments. The antitumor activity of compound 112, administered po, showed more potent in vivo oral antitumor activity than gambogic acid.
Biomimetic total synthesis of forbesione and desoxymorellin utilizing a tandem Claisen/Diels–Alder/Claisen rearrangement
作者:Eric J. Tisdale、Irina Slobodov、Emmanuel A. Theodorakis
DOI:10.1039/b311833a
日期:——
A concise synthesis of forbesione (1) and desoxymorellin (3) is presented. Central to the strategy is a biomimetic Claisen/DielsâAlder/Claisen reaction cascade that proceeds in a regioselective manner and produces the desired scaffold exclusively. The observed regioselectivity and product distribution of the Claisen/DielsâAlder/Claisen reaction are attributed to the electronic effects of the xanthone oxygen (O10), the C9 carbonyl group and the nature of the C1 functionality.