7-Keto Steroids. II.¹ Steroidal 3β-Hydroxy-Δ⁵-7-ones and Δ^3,5-7-Ones

Abstract

A series of steroidal 3/3-hydroxy-''-7-ones and A3|5-7-ones were prepared as potential anti-cortisone agents. Biological evaluation showed 7-ketopregnenolone, 7-keto-21-acetoxypregnenolone 3-acetate and pregna-3,5-diene-7,20-dione to have a mild order of activity. The 3/3-hydroxy (or acetoxy)-A6-7-ones were prepared by oxidation in the allylic (C-7) position with either f-butyl chromate or sodium chromate. The A3'5-diene-7-ones were prepared by boiling the 3/3-acyloxy-A5-7ones one hour in glacial acetic acid with 0.5% (w./v.) of /j-toluenesulfonic acid.

The allylic oxidation of unsaturated steroids by tert-butyl hydroperoxide using surface functionalised silica supported metal catalysts

“…The D 5 -steroids can be oxidised to 5-en-7-ones, which are known as inhibitors of sterol biosynthesis and have some use in cancer chemotherapy. 3 The allylic oxidation of unsaturated steroids such as D 5steroids, has traditionally been performed with chromium reagents such as CrO 3 -pyridine complex, 4 CrO 3 and 3,5-dimethylpyrazole, 5 pyridinium chlorochromate, (PCC), 6,7 pyridinium dichromate (PDC), 7 sodium chromate, 8 sodium dichromate in acetic acid, 9 pyridinium fluorochromate, 10 and 3,5-dimethylpirazolium fluorochromate(VI). 11 However, the great excess of ecologically and physiologically undesirable chromium reagent and the large volume of solvent required in these procedures, in combination with the difficult work-up and the production of environmentally hazardous chromium residues, causes such procedures to be inconvenient on a commercial scale.…”

22,23-Epoxides of Sitosterol and Related 7-Oxygenated Δ5-Sterols

“…The synthesis of target ( X )-( XV ) from the acetates ( IV ) and ( V ) was carried out according to the known procedures of the cholesterol acetate conversion into the corresponding 7-oxygenated derivatives [27,28]. The allyl oxidation of ( IV ) and ( V ) with K 2 Cr 2 O 7 in an AcOH-Ac 2 O mixture led to ~60% yields of acetates ( VI ) and ( VII ), respectively.…”

Metal‐Free Allylic Oxidation of Steroids Using TBAI/TBHP Organocatalytic Protocol

“…For instance, 7-oxocholesterol shows high potencyi nanti-cancer treatment [2] and 7-oxo-dehydroepiandrosterone (7-oxo-DEHA)w as found to be effective in inducing thermogenic enzymes and enhancement of memory in old mice. [3,4] Classicalm ethodsf or allylic oxidation involvet he use of chromium (VI) reagents, such as chromium trioxide, [5] chromium pyridinium chlorochromate [6] and chromium trioxide-pyridine complex. [7] However,e nvironmentally hazardous chromium residues are produced in the processes.…”