Approach towards an EPC synthesis of nodusmicin - III. Preparation of the oxygen bridged decalin part of nodusmicin

Article abstract of DOI:10.1016/S0040-4020(97)00065-3

Starting with the unsaturated 1,4-mesa-diol 1, the enantiomerically pure 4-silyloxy enone 6 is prepared in high yields via diastereomeric acetals and equilibration. Enone 6 is converted to the cis-decalinone derivative 17 with fragmentation as the key step. Consequently oxidation to the conjugated enedione 24, reduction to the enediol 25 and intramolecular oxymercuration produces, depending on the reaction conditions, either the unsaturated tricyclic ether 27, which constitutes a link to a known 18-deoxynargenicin synthesis, or the saturated tricyclic ether 26, which represents the starting material for the construction of the tenmembered ring of nodusmicin.