SYNTHESIS, ACTIVITY, AND REACTIVITY OF 9-BORASTEROIDS

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It is proposed to prepare racemic cortisone by two very different routes and optically active cortisone using a resolved starting material for one of these routes the overall approach to the corticoid steroids is a test of boron annelation (hydroboration and carbonylation or equivalent reaction) as a synthetic tool. In addition the synthesis of androstandione, fichtelite, hibanone, kaurene and the basic skeletal system of aphidicolin (and similar compounds) are proposed employing newly developed variations on boron annelation. These propositions are designed (a) to carefully evaluate a new approach to steroid (and natural product) synthesis, (b) to provide medicinally important drugs (cortisone, etc.), as well as allow for evaluation (testing) of a new class of "hetero"-steroids (borasteroids) and (c) to answer certain important chemical questions concerning the usage of carboranes in complex natural product synthesis. It is of chemical significance that a triene will be converted to cortisone and optically active cortisone. Various dienes have been designed to evaluate the effect of "remote" Lewis base and other influences on hydroboration/carbonylation in forming the other natural product target systems. All compounds prepared will be evaluated for actvity with general screening being done at Lederle' Drug Co., Shell Oil and with certain specific types of activity (anticancer, antileukemic) being done at U.S.C.