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31.
Jyh-Horng Sheu Kuie-Chi Chang Ping-Jyun Sung Chang-Yih Duh Ya-Ching Shen 《中国化学会会志》1999,46(2):253-257
A new marine sterol 7β-hydroperoxy-24-methylenecholesterol ( 1 ) along with five known compounds sarcophytol A ( 2 ), (Z)-N-[2-(4-hydroxyphenyl)ethyl]-3-methyldodec-2-enamide ( 3 ), 5α,7αH-eduesm-11(13)en-4α-ol ( 4 ), 24-methylenecholesterol ( 5 ) and 1β-hydroxy-α-cyperone ( 6 ) have been isolated from a Formosan soft coral Sinularia sp. The structures of the above compounds were determined by spectral analyses. Cytotoxicity of compounds 1–6 toward various cancer cell lines also is reported. 相似文献
32.
Vieira HS Takahashi JA Gunatilaka AA Boaventura MA 《Magnetic resonance in chemistry : MRC》2006,44(2):146-150
A highly rearranged novel dilactone was the single product isolated from Baeyer-Villiger oxidation of a norketone prepared from grandiflorenic acid, a natural kaurane diterpene. The complete 1H and 13C NMR assignment is presented for this novel compound that showed discrete in vitro antibacterial activity. 相似文献
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M. S. Yunusov E. M. Tsyrlina E. D. Khairitdinova L. V. Spirikhin A. Yu. Kovalevsky M. Yu. Antipin 《Russian Chemical Bulletin》2000,49(9):1629-1633
A new alkaloid, anhydrolycaconitine (C36H46N2O9), was isolated from roots ofAconitum septentrionale K. Based on the results of1H and13C NMR and IR spectroscopy and mass spectrometry of the alkaloid and the product of its alkaline hydrolysis and on the data
of X-ray diffraction analysis of the hydrolysis product, the structure of 1α, 6β, 14α, 16β-tetramethoxy-7-oxo-18-succinylanthranoyloxy-17-(7→8)abeo-aconane was assigned to anhydrolycaconitine.
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1640–1644, September, 2000. 相似文献
35.
The first synthesis of 3(S),17-dihydroxytanshinone was achieved by ultrasound promoted Diels-Alder reaction of the protected 3-hydroxymethyl-4,5-benzofurandione with a vinylcyclohexene derivative. Bioassay showed that the synthetic 3(S),17-dihydroxytanshinone was active in vitro against HL-60 tumor cell line by MTT method. 相似文献
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Two dimeric grayanane diterpenes with a novel 3-O-2 linkage, birhodomolleins D (1) and E (2), were isolated and structurally elucidated from the fruits of Rhododendron pumilum. Their structures were fully determined by comprehensive analysis of spectroscopic data. 相似文献
37.
Le Ba Vinh Nguyen Thi Minh Nguyet Seo Young Yang Jang Hoon Kim Le Thi Vien Phan Thi Thanh Huong 《Natural product research》2018,32(17):2001-2007
Eight compounds were isolated from the leaves of Clerodendrum inerme, including one new rearranged abietane diterpene, crolerodendrum B (1). Their structures were determined by means of spectroscopic methods including one-dimensional and two-dimensional nuclear magnetic resonance (1-D and 2-DNMR), high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) and circular dichroism (CD). The DPPH radical scavenging and cytotoxic activities of isolated compounds against MCF7 (breast), HCT116 (colon) and B16F10 (melanoma) cancer cell lines were evaluated. Compounds 1, 3 and 4 exhibited strong DPPH radical-scavenging effects (ED50 values of 17.6 ± 2.1, 10.1 ± 0.8 and 11.3 ± 0.3 μM, respectively) and 4 showed strong cytotoxicity against the HCT116 cell line (IC50 = 3.46 ± 0.01 μM). 相似文献
38.
Nguyen Van Minh Baek-Soo Han Ha-Young Choi JeongSu Byun Ji-Su Park 《Natural product research》2018,32(15):1782-1790
Screening for new natural anti-neuroinflammatory compounds was performed with the traditional folk medicine Genkwa Flos, which potently inhibited nitric oxide (NO) production by LPS-activated microglial BV-2 cells. Two new lathyrane-type diterpenes, genkwalathins A (1) and B (2), and 14 known daphnane-type diterpenes (3–16) were isolated. The lathyrane-type diterpenes were isolated for the first time from the Thymelaeaceae family in this study. Compounds 1 and 2 moderately inhibited LPS-induced NO production in BV-2 cells without affecting cell viability, while six daphnane-type diterpenes (3, 4, 6, 7, 9 and 10) potently reduced NO production with IC50 values less than 1 μM, although they did display weak cytotoxicity. A structure–activity relationship study on the daphnane-type diterpenes indicated that the stereochemistry at C-19, the benzoate group at C-20, and the epoxide moiety could be important for their anti-neuroinflammatory effects. 相似文献
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