Phytochemical investigations of the leaves and flowers of Hibiscus rosa-sinensis L.

Hibiscus rosa-sinensis L. (Malvaceae) is an ornamental and medicinal plant used to treat asthma, cough, boils, wounds, ringworm, gynecological conditions, hair loss, dandruff, itchy scalp, obesity, sexual diseases, cough, cold and venereal diseases. This study was designed to isolate chemical constituents from the leaves and flowers of H. rosa-sinensis and to characterize their structures. A methanolic extract of the leaves afforded isolation of n-tetracosanyl cyclopentylcarboxylate (1), taraxerol acetate (2) and 26β- cyclopentanyl n-hexacosan-5β-ol (3) along with n-hexatetracontane (4), β-sitosterol (5), stigmasterol (6), urs-12-en-3β-ol-18β-H-30-oic acid, dulcioic acid, 7), urs-12-en-3β-ol-18β-H-27-oic acid, peltoboykinolic acid, 8), urs-12-en-3β-ol-18β-H-29-oic acid, maprounic acid, 9), oleanolic acid (10) and β-sitosterol 3-O- β-D-xylopyranoside (11) from methanolic fractions of flowers. The structures of these compounds were elucidated on the basis of spectral data analysis and by chemical reactions.