@article{1aee992d4b514c498a373ccf8a39379f,
title = "Steroids and related natural products. Part XCII. Conversion of canarigenone[14-hydroxy-3-oxo-14β-carda-4,20(22)-dienolide] into periplogenin [3β,5,14-trihydroxy-5β,14β-card-20(22)-enolide]",
abstract = "Oxidation of canarigenone (IV) by peroxy-acid gave the 4β,5β-epoxide (V), which was reduced by chromium(II) acetate to the 5β-hydroxy-3-ketone (VI). Selective reduction of this with Urushibara nickel A led to periplogenin (Ia). The epoxy-ketone (V) was also prepared from canarigenin (VII). Since digitoxigenin (III) had previously been converted to canarigenin (VII) and canarigenone (VI) the synthetic route to periplogenin constituted a formal total synthesis.",
author = "Yoshiaki Kamano and George Pettit and Machiko Tozawa",
note = "Funding Information: 233-238'.Use of chromium trioxide (10 mg) in acetic acid (7 ml)(room temperature, 2 h) similarly gave the hydroxy-ketone(VI) (12 mg), m.p. 230-237'.Periplogenin (Ia) (20 mg)in methanol (2 m1)-acetone (1 ml), was treated with N-bromoacetamide (22 mg) in methanol (0.4 m1)-water (0.1 ml)for 42 h a t 20 {"}C. The mixture was poured into ice-waterand extracted with methylene chloride. The extract waswashed with water, dilute aqueous sodium sulphite andwater, and evaporated. The residue was purified by pre-parative t.1.c. as in method (A) to give the hydroxy-ketone(VI) (11 mg), m.p. 231-237{"}.The product from both methods identical with thehydroxy-ketone (VI) prepared from canarigenone.(B) Reduction wath Urushibara nickel A .354 (M+-AcOH-HH,O).(B) W i t h N-bromoacetamide.This investigation was supported by Public HealthService Research Grants from the National Cancer Instituteand was performed pursuant to a contract with the Divisionof Cancer Treatment, National Cancer Institute, Depart-ment of Health, Education, and Welfare. We are alsograteful for financial support from the J. W. KieckheferFoundation, the Fannie E. Rippel Foundation, the SaltRiver Project of Arizona, Mrs. Virginia Bayless, and theArizona Public Service Company.[6/466 Received, 10th March, 1976116 P. Speiser and T. Reichstein, Helv. Chim. Acta, 1947, 80,2143; A. Lardon, abid., 1960, 38, 639",
year = "1975",
doi = "10.1039/P19750001976",
language = "English (US)",
pages = "1976--1978",
journal = "Journal of the Chemical Society, Perkin Transactions 1",
issn = "1470-4358",
publisher = "Chemical Society",
number = "19",
}