New stereoselective route to the epoxyquinol core of manumycin-type natural products. synthesis of enantiopure (+)-bromoxone, (-)-LL-C10037α, and (+)-KT 8110

A practical route is decribed for the preparation of the C7N core of manumycin-type compounds. Starting from p-benzoquinone, optically pure compounds in both forms can be prepared via enzymatic resolution of a derived diacetoxy conduritol. A diepoxy aminoinositol is accessible which can function for formation of enantiopure epoxyquinones and quinols. Examples are given for acylation reactions of this amine with several acyl derivatives. With this approach (-)-LL-C10037 alpha and quinones such as (+)-KT-8110 with 5R,GS-configuration can be synthesized through oxidation. In addition a short route to (+)-bromoxone is described. Most steps include simple epoxide formation and cleavage reactions which all can be carried out in a high stereoselective manner.