Steroidal Sapogenins. XIV.¹ Δ^{4, 6}-22-Isospirostadien-3β-Ol and Δ^{2, 4, 6}-Isospirostatriene

Δ5,7-Steroids. XVI. Steroidal Cyclic Ketals. VI.1,2 The Preparation and Transformation Products of Δ5,7-22a-Spirostadiene-3-one-Ethylene Ketal

“…), ethylene glycol (10 ml. ), and p-toluenesulfonic acid monohydrate (60 mg.) was reacted in the same manner as described in a previous publication (la) (reflux 4 Al~$%a-Spirostene-3-one-(%'-dimethyl)trimethylene ketal (lib). A mixture of I (3 g.),…”

“…material prior to bromination and dehydrobromination. 4 The preparation of the 4 6-3-ß (IV) directly from the 4-3-ß (I) has been reported by Romo, Ringold, Rosenkranz, and Djerassi (4). We have successfully repeated this preparation, but find minor discrepancies in the characterization of IV, especially in regard to its ultraviolet absorption spectrum.…”