Isolation of two new sterols from clerodendrum campbellii

✍ Scribed by Loretta M. Bolger; H.H. Rees; E.L. Ghisalberti; L.J. Goad; T.W. Goodwin

• Publisher: Elsevier Science
• Year: 1970
• Tongue: French
• Weight: 229 KB
• Volume: 11
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)98409-6

✦ Synopsis

The occurrbnce of A25-sterols has been reported i-7 in a number of plants, including Clerodendrum species. The present communication reports the isolation and characterization of two new sterols, (24~)-ethyl-cholesta-5,22,25-trien-3b-o1 and 24f-ethyl-4c-methyl-cholesta-7,25-dien3S-01, from Clerodendrum camubellii. Freeze-dried leaves of C. camubellij were extracted with ethanol, the lipid saponified and the 3khydroxy sterols precipitated with digitonin. The regenerated sterols were separated into 4,4-dimethyl,4o_methyl and 4desmethyl sterols. 4-Desmethvl sterolq. G.L.C. (W-1 and SE-3Go) of this fraction showed a single peak of identical retention time to that of stigmasterol (I) and poriferasterol (II). Treatment with the Liebermann-Humhard reagent gave a blue-green colour, k-max 620 nmv which reached a maximum intensity after 33 min. indicative of aA bond. Recrystallization gave crystals of m.p. 146OC (acetate m.p. = 14lOC); CaJL?==-37.8 (CHC13); I.R.,I/mu 890, 1645 cm-' (terminal methylene), 965 cm-' (m disubstituted double bond), 800 cm-' (trisubstituted double bond);