| Abstract
| - Estrogenicity-directed fractionation of a methanol extract of the strobiles of Humulus lupulus that hadbeen extracted previously with supercritical CO2, known as “spent hops”, led to the isolation andidentification of 22 compounds including 12 prenylated chalcones (1−8, 10−13), five prenylflavanones(14−17), 4-hydroxybenzaldehyde (18), sitosterol-3-O-β-glucopyranoside (19), humulinone (20), andcohumulinone (21). In addition, the prenylated chalcone xanthohumol C (9a) was obtained as a 6:1 mixturealong with its 1‘ ‘,2‘ ‘-dihydro derivative (9b). Three new chalcones (4, 11, 12) and four previously unreportedconstituents of hops (5, 6, 9b, 13) are reported. The structures of the new compounds were determined through a combination of spectrometric techniques including 1D and 2D NMR, HRESIMS, andESIMS-MS. Full 1H NMR spin system analyses were performed to characterize the higher-orderglucopyranosyl, prenyl, and chalcone B-ring spectra of the isolates. The principle estrogen 8-prenylnaringenin (15) from hops is an artifact formed along with its positional isomer 6-prenylnaringenin (16)through the spontaneous isomerization of the pro-estrogenic chalcone DMX (7).
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