Expeditious Synthesis of Mycobacterium tuberculosis Sulfolipids SL-1 and Ac2SGL Analogues

M. tuberculosis sulfoglycolipids SL-1 and Ac2SGL are highly immunogenic and potential vaccine candidates. A short and efficient methodology is reported for the synthesis of SL-1 and Ac2SGL analogues via regioselective functionalization of α,α-D-trehalose employing a highly regioselective late stage sulfation, as a key step. The SL-1 analogues 3a and 4 were obtained in 10 and 9 steps in 13.4% and 23.9% overall yields, respectively. The Ac2SGL analogue 5 was synthesized in 5 steps in 18.4% yield.