Synthesis of Hydrophenanthrene Natural Products. An Improved Synthesis of 13-Substituted Dehydroabietane Derivatives from Dehydroabietic Acid

Abstract An improved overall synthesis of 13-carboxydeisopropyldehydro-abietanes from dehydroabietic acid is reported. This important synthetic intermediate is obtained in greater than 20% overall yield, an almost tenfold increase in the yield obtained using previously published procedures. The first synthesis of 15-hydroxydehydroabietanol, a natural product isolated from pine tar oil and an intermediate in the preparation of the title compound, has been accomplished.