“…A broad spectrum of other bioassays carried out in conjunction with the isolation of new flavonol O-glycosides (Table 2) includes assessment of allergy-preventive activity (286), aminopeptidase N inhibition (194, 195, 209, 220-223, 236, 273, 295, 296, 312, 317, 318, 348, 349), antifungal activity (180,245,249,250), anti-HIV-1 activity (371,372), anti-inflammatory activity (275), anti-methicillin-resistant Staphylococcus aureus (MRSA) activity (196)(197)(198), cyclooxygenase inhibition (283, 375), cytotoxicity (175,253,254,322,345), estrogenic activity (225,226), a-glucosidase inhibition (170,200,218), hepatoprotective activity (178,194,195,274,296,315), and myeloperoxidase inhibition (192). Bioassay-guided fractionation of MeOH extracts of the petals of the ornamental plant Hibiscus mutabilis 'Versicolor' for allergy-preventive constituents yielded 5 flavonols, of which mutabiloside (286) and the known analogue quercetin 3-O-b-xylopyranosyl-(1/2)-b-galactopyranoside had activity comparable to a number of clinically-used products, including disodium cromoglycate.…”