Studies toward the Total Synthesis of Mumbaistatin, a Highly Potent Glucose-6-phosphate Translocase Inhibitor. Synthesis of a Mumbaistatin Analogue

A strategy for the total synthesis of the highly potent glucose-6-phosphate translocase inhibitor mumbaistatin (1) and structural analogues was elaborated. Such compounds represent a lead structure in the development of potential new drugs for the treatment of diabetes. To evaluate the general strategy, the close mumbaistatin analogue 10 was synthesized in a convergent manner. The anthraquinone building block 20 was efficiently prepared via aryne/phthalide annulation. After conversion of 20 into the corresponding 9,10-dimethoxyanthracene-1-carbaldehyde derivative (13), coupling with a lithiated arene (12) and subsequent multiple oxidation under Jones conditions yielded the mumbaistatin analogue 10. The preparation of the functionalized arene intermediates was achieved exploiting highly regioselective bromination and ortho-lithiation reactions.