In a preceding publication (1), the transformation of pregnane-20one-3(/3), 5,6(frans)-triol into pregnane-3,20-dione-5, 6(frons)-diol 6-monoacetate was discussed. This series of reactions involved the partial saponification of the 3,6-diacetate of the 3,5,6-triol and the subsequent oxidation with chromic acid of the 6-monoacetate. We have been interested in utilizing other methods which lead to the two possible partial oxidation-products of 3,5,6-triols, namely, the corresponding 3-one-5,6diols or 6-one-3,5-diols. A simple procedure would obviously consist in the partial oxidation by chromic acid of the free 3,5,6-triols. It remains to be shown whether such an oxidation always attacks the same carbon atom preferentially, regardless of the configurations at carbon atoms 3, 5, and 6, or whether the course of this reaction is determined by the stereochemical arrangement at the asymmetric centers mentioned.

Pflln a previous publication (1) 3,5,14-trihydroxyestrane-10,17-dicarboxylic acid served as an intermediate in the preparation of compounds structurally related to hormones of the pregnane series. The dicarboxylic acid was prepared from strophanthidin (I) according to procedures known from the literature.The stepwise degradation of the unsaturated lactone ring is a time-consuming and uneconomical procedure which, in addition, is associated with an undesired inversion of the configuration at carbon atom 17.Doubts have recently arisen regarding the presently accepted stereochemical structure of strophanthidin.2 Ruzicka (2) states for instance that certain reactions of strophanthidin are not in agreement with the configuration of a derivative of 3(a) ,5-dihydroxycoprostane. Very recent work from the same laboratory (3) supports the assumption that in the normal, naturally-occurring, sterids the side chain at carbon atom 17 is attached in /3-position.2a According to this postulation, the part of ring D in the cardiac aglycons has to be

In an earlier publication (1) a procedure was described for the preparation of certain steroids which are substituted at carbon atom 6 by an acetoxyl group. The arrangement in ring A of these compounds was the same as in the most active hormones of the androstane and pregnane series. Hence carbon atom 3 existed as carbonyl carbon and there was a double bond between carbon atoms 4 and 5. The examples given were the preparation of 6(a)-acetoxyandrostenedione and of 6(a)-acetoxydesoxycorticosterone. It was pointed out that 6(a) -acetoxyprogesterone (VI) previously obtained by Ehrenstein and Stevens (2) according to another procedure should also be accessible by means of the new scheme. The present investigation demonstrates that this is actually the case and that the new method is preferable to the old one.Starting material for this sequence of reactions was 5-pregnene-20-one-3(/3)-ol (I). Treatment of this substance with perbenzoic acid yielded mainly (65%) the (5,6)(a)-oxide (II) as was shown by the subsequent reactions. It was pointed out in the earlier paper (1) that (5,6) (a)-oxides furnish with glacial acetic acid 6-acetoxy compounds, whereas (5,6)(dioxides yield 5-acetoxy compounds. When pregnane-(5,6)(a)-oxide-20one-3(/3)-ol (II) was treated with glacial acetic acid under proper experimental conditions, only a small quantity of the by-product, pregnane-20one-3(j3), 5,6(¿rans)-triol 3,6-diacetate (IV), resulted. The main product (61.3%) of the reaction was pregnane-2O-one-3(0) ,5,6(trans)-triol 6monoacetate (III). Acetylation of this compound with acetic anhydride yielded the above mentioned 3,6-diacetate (IV).We had previously prepared (2) the 6-monoacetate (III) by partial hydrolysis of the 3,6-diacetate (IV). For the 6-monoacetate (III) the melting point 222-226°was observed. The melting point of the same compound obtained by acetolysis of the (5,6)(a)-oxide (II), however, was 1 Aided by a grant from the Smith, Kline, and French Laboratories in Philadelphia.Read before the Division of Organic Chemistry at the St. Louis meeting of the

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