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Osteospermum vaillantii (Decne) T. Norl., collected from southern Saudi Arabia, yielded two new saponins characterised as 3-O-beta-D-glucopyranosyl-(2' --> 1'')-beta-D-glucopyranosyl-(3' --> 1''')-O-beta-D-galactopyranosyl-oleanolic acid, designated as osteosaponin, and 3-O-beta-D-glucopyranosyl-(2' --> 1'')-beta-D-glucopyranosyl-(2''-1''''')-beta-D-glucopyranosyl-(3' --> 1''')-O-beta-(-D-galactopyranosyl-oleanolic-acid-28-C(O)-O-beta-D-(1'''')-glucopyranosyl ester, designated as osteosaponin. The sugar attachments and configurations were confirmed by spectroscopic methods, that is, 1H, 13C-NMR, COSY, HSQC and HMBC-NMR experiments.

Three new diterpenes, namely jasonin-a (1), jasonin-b (2), and jasonin-c (3) were isolated from the aerial parts of Jasonia montana (Asteraceae). Their structures were elucidated on the basis of spectral data as [(1E)-2-((2S)-1,2,5-trimethylbicyclo[3.2.l]octan-8-yl)vinyl] benzene-3-carboxylic acid (1), [3-((2S, 5S)-1,2, 5-trimethylcycloheptanyl)propyl]benzene-3-carboxylic acid (2), and [(1E)-3-((7R)-1,7-dimethy-4-methylenecycloheptanyl)prop-1-enyl] benzene-3-carboxylic acid (3). In addition, the previously reported 5,7,3'-trihydroxy-3,6,4'-trimethoxy flavone designated as centaureidin (4), was also isolated and characterized from this source. The different extracts of the plant were also screened for hypoglycemic, antidiabetic, and antimicrobial activities, wherein the petroleum ether and ethanolic extracts exhibited hypoglycemic and antidiabetic activity, and the petroleum ether and chloroform extracts showed antimicrobial activity.

A new compound derivative of glycoside 19-α-hydroxy-ursolic acid glucoside (19-α-hydroxyurs-12(13)-ene-28-oic acid-3- O-β- d-glucopyranoside (HEG) was isolated from whole plant of Wedelia calendulacea (Compositae). The structure was elucidated and established by standard spectroscopy approaches. Diethylnitrosamine (DEN) (200 mg/kg) and ferric nitrilotriacetate (Fe-NTA) (9 mg/kg) were used for induction of renal cell carcinoma (RCC) in the rats. The rats were further divided into different groups and were treated with HEG doses for 22 weeks. Anti-cancer effect in RCC by HEG was dose dependent to restrict the macroscopical changes as compared to DEN + Fe-NTA-control animals. Significant alteration in biochemical parameters and dose-dependent alleviation in Phase I and Phase II antioxidant enzymes were responsible for its chemo-protective nature. HEG in dose-dependent manner was significant to alter the elevated levels of pro-inflammatory cytokines and inflammatory mediators during RCC. The histopathological changes were observed in the HEG pre-treated group, which was proof for its safety concern as far as its toxicity is concerned. The isolated compound HEG can impart momentous chemo-protection against experimental RCC by suppressing the cyclooxygenase (COX-2) and prostaglandin E2 (PGE) expression via nuclear factor-kappa B (NF-κB) pathway. [ABSTRACT FROM AUTHOR]

Three new furanoeremophilanes have been obtained from the aerial parts of Senecio asirensis (N. O. Asteraceae), and characterized as 6-hydroxylmethyl-9-methoxyl-4,11-dimethylnaphtho[2,3- b ]furan, designated asirensane-a ( 1 ), 6-hydroxyl-1,2-dimethoxyl-4,6,11-trimethyl-6-hydronaphtho[2,3- a ]furan-7-one, named asirensane-b ( 2 ), and (6,12-dihydroxyl-9-methoxyl-4-methyl-11-acetyl-3,4-dihydronaphtho[2,3- b ]furan-3-yl)methyl (2′ Z )-2′-methylbut-2′-enoate, designated asirensane-c ( 3 ). In addition, two rare furanoeremophilanes have also been isolated and characterized from this source, namely 9-methoxyl-4,11-dimethylnaphtho[2,3- b ]furan, named 14-nordehydrocalohastine ( 4 ), and 4,11-dimethylnaphtho[2,3- b ]furan-6,9-dione, designated as maturinone ( 5 ). Their structures have been elucidated on the basis of spectral analysis. The alcoholic extract was also tested for anti-inflammatory activity, which decreased edema by 22% at a dose of 500 mg kg -1 after 3 h with respect to the control group treated only with carrageenan, while the standard drug phenylbutazone showed a 50% decrease at a dose of 100 mg kg -1 , indicating that the extract has moderate anti-inflammatory activity. [ABSTRACT FROM AUTHOR]