Synthesis of Mansonone F Based on the Regioselective Hydrolysis of a Hydroquinone Diacetate

The synthesis of mansonone F (1), an antimicrobial sesquiterpenequinone, is described. Starting from 2,5-dimethyl-1,4-naphthoquinone (5), the corresponding selectively protected hydroquinone 9 was prepared in four steps. Alkylation of 9 using chloroacetone, cyclization, and oxidation to the o-quinone completed the reaction sequence in 7.5% overall yield. The regioselectivity for the basic hydrolysis of hydroquinone diacetate 6 was discussed on the basis of MO calculations.