Continuing a study of the oxidizing capacity of the fungus Ci rc ine l la muscae , we have fermented 3fihydroxypregna-5 ,16-d ien-20-one (16-dehydropregnenolone) (I) with this s t ra in . 2.0 g of 16-dehydropregnenolone was added to a grown cul ture. After incubation, 1.25 g of a substance was obtained with the formula C21H3004 (II), mp 238243 ° C,[~]~s--98.0° (el.00 , UV spec t rum: ~C~H~OIt 241 mp (log e 4.04). The IR spectrum of compound II has absorption bands at 3250-3400 cm -1 (hydroxyl groups) and at 1660 and 1590 cm -1 (c~,fi-unsaturated keto grouping). Calculation of the protons in the NMR spect rum of II ca r r i ed out before and after the displacement of the protons of the OH groups with t r i f luoroacet ic acid showed the p resence in the substance of two secondary and one te r t ia ry hydroxyl groups. Product II is not oxidized by NaIO4. The acetylat ion of II (acetic anhydr ide-pyr id ine , 36 ° C, 72 hr) gave a diacetate C25H3406 (III) with mp 165-167 ° C, [~]108-192,3 ° (c 1.05 ; chloroform).