Triterpenes and sterols from Hoya diversifolia Blume.

Chemical investigation of the dichloromethane extracts of Hoya diversifolia Blume led to the isolation of β-amyrin cinnamate (1), squalene (2), β-sitosterol (3), a mixture of β-amyrin (4a), α-amyrin (4b) and lupeol (4c) in a 4:2:1 ratio and saturated hydrocarbons from the leaves; and 2, taraxerol (5), lupeol cinnamate (6), and a mixture of 3 and stigmasterol (7) in a 2:1 ratio from the stems. The structures of 1-7 were identified by comparison of their NMR data with those reported in the literature.

Chemical Constituents of Hoya buotii Kloppenb.

Chemical investigation of the dichloromethane extracts of Hoya buotii Kloppenb. afforded taraxerone (1), taraxerol (2), a mixture of β-sitosterol (3a) and stigmasterol (3b) in about 2:1 ratio, and a mixture of α-amyrin cinnamate (4a) and β-amyrin cinnamate (4b) in about 1:2 ratio from the stems; 1, 2, and 3a from the roots; a mixture of 4a and 4b in about 3:2 ratio from the flowers; and 3a, squalene (5) and saturated hydrocarbons from the leaves. The structures of 1-5 were identified by comparison of their NMR data with those reported in the literature.

Cytotoxic Triterpenes and Sterols from Pipturus arborescens (Link) C.B. Rob.

The triterpenes, squalene (1), friedelin (2) and a mixture of ursolic acid (3a) and oleanolic acid (3b) in a 2:3 ratio, and a mixture of β-sitosterol (4a) and stigmasterol (4b) in a 2:1 ratio, obtained from the dichloromethane extract of Pipturus arborescens (Link) C.B. Rob., were evaluated for their anti-proliferative activities against three human cancer cell lines, breast (MCF-7) and colon (HT-29 and HCT-116), and a normal cell line, human dermal fibroblast- neonatal (HDFn) using the in vitro PrestoBlue® cell viability assay. The HCT-116 cell line was most susceptible to the compounds and mixtures tested. Triterpene 1 was most cytotoxic against HCT-116 and MCF-7 with IC50 values of 4.21 and 5.92 μg/mL, respectively. Triterpene 2 and the mixture of 3a and 3b were highly anti-proliferative against HCT-116 cells (IC50 of 1.22 and 1.66 μg/mL, respectively) and moderately inhibitory against MCF-7 cells (IC50 of 16.51 and 23.97 μg/mL, respectively). The mixture of 4a and 4b exhibited high cytotoxicity against HCT-116 cells (IC50 of 1.14 μg/mL). Compounds 1-4b showed the least activity against HT-29 cells (IC50 of 11.97 to 52.52 μg/mL). Cytotoxic effect was not observed against HDFn cells (>100 μg/mL). Comparing the effects of 1-4b on the two colon cancer cell lines, the IC50 values of 1-4b against HCT-116 were lower than those of HT-29.

Chemical Constituents of Cordia dichotoma G. Forst.

Chemical investigation of the dichloromethane extracts of Cordia dichotoma G. Forst led to the isolation of β- sitosteryl-3β-glucopyranoside-6'-O-palmitate (1), nervonyl 4-hydroxy-trans-cinnamate ester (2), β-sitosterol (3), and chlorophyll a (4) from the leaves; and 4 and 1,2-dilinoleoyl-3-linolenoylglycerol (5) from the twigs. The structures of 1-5 were identified by comparison of their NMR data with those reported in the literature. The fatty acids in 1, 2 and 5 were deduced from ESI-MS data.

Chemical Constituents of Ixora philippinensis Merr.

Chemical investigations of the dichloromethane extracts of Ixora philippinensis Merr., a plant endemic to the Philippines, led to the isolation of syringaresinol (1), pinoresinol (2), isoscopoletin (3), squalene (4), β-sitosterol (5a), and stigmasterol (5b) from the stems; and 4, 5a, 5b, lupeol (6), and lutein (7) from the leaves. The structures of 1 and 3 were elucidated by extensive 1D and 2D NMR spectroscopy, while those of 2 and 4-7 were identified by comparison of their NMR data with literature data.

Chemical constituents of Cycas aenigma.

Chemical investigation of Cycas aenigma, a plant endemic to the Philippines, led to the isolation of a rare neolignan, 2-[2-hydroxy-5-(3-hydroxypropyl)-3-methoxyphenyl]-1-(4-hydroxy-3-methoxyphenyl)propane-1,3-diol (1), pinoresinol (2), and fatty alcohols (3) from the leaflets; and triglycerols (4), and a mixture of β-sitosterol (5a) and stigmasterol (5b) from the petiole and rachis. The structure of 1 was elucidated by extensive 1D and 2D NMR spectroscopy, while those of 2-5b were identified by comparison of their 1H and/or 13C NMR data with literature data.

Chemical Constituents of Cycas sancti-lasallei.

Chemical investigation of the dichloromethane extracts of Cycas sancti-lasallei, a plant endemic to the Philippines, led to the isolation of squalene (1), β-sitosterol (2a), stigmasterol (2b), and triglycerides (3) from the sarcotesta; 2a, 2b, 3,and phytyl fatty acid esters (4) from the endotesta; 2a, 2b, 3,and β-sitosteryl fatty acid esters (5) from the sclerotesta; and 3 and 5 from the bark. The structures of 1-5 were identified by comparison of their 1H NMR and/or 13C NMR data with those reported in the literature.

Triterpenes and Acylglycerols from Canarium ovatum.

Chemical investigations of the dichloromethane extracts of the leaves of Canarium ovatum Engl. afforded β- amyrin (1a), α-amyrin (1b), epi-β-amyrin (2a), epi-α-amyrin (2b), epi-lupeol (2c), β-carotene (3) and lutein (4); while the twigs yielded 1a-1b. The dichloromethane extracts of the fruits of C. ovatum yielded triacylglycerols (5); the mesocarp also afforded 1a, 1b, 1,2-dioleylglycerol (6), and monounsaturated and saturated fatty acids; the nutshell also provided 6; and the kernel also yielded monounsaturated and saturated fatty acids. The structures of 1-6 and the fatty acids were identified by comparison of their 1H and/or 13C NMR data with those reported in the literature.

Terpenoids and Sterols from Hoya multiflora Blume.

Chemical investigation of the dichloromethane extracts of Hoya multiflora Blume led to the isolation of lupeol (1a), α-amyrin (1b), β-amyrin (1c), lupeol acetate (2a), α-amyrin acetate (2b), and β-amyrin acetate (2c) from the stems; and 1b, bauerenol (3), squalene (4), lutein (5), β-sitosterol (6a), and stigmasterol (6b)from the leaves. The structures of 1-6 were identified by comparison of their 1H and/or13C NMR data with those reported in the literature.

Triterpenes and Sterol from Artocarpus ovatus.

Chemical investigation of the dichloromethane extract of the twigs of Artocarpus ovatus afforded lupeol (1a), α- amyrin (1b), β-amyrin (1c), lupeol fatty acid ester (2a), α-amyrin fatty acid ester (2b), β-myrin fatty acid ester (2c), betulin (3a), 3β, 28-Dihydroxyolean-12-ene (3b), oleanolic acid (4), β-sitosterol (5), and chlorophyll a (6). The structures of 1-6 were identified by comparison of their 1H and/or 13C NMR data with those reported in the literature.