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71.
Sudhakar Mokenapelli Madhu Gutam Ramana Govu Vijay Kumar Pasala Jayaprakash Rao Yerrabelly 《合成通讯》2019,49(10):1241-1251
A new IBX mediated protocol for regio/chemoselective oxidation of andrographolide (1), a labdane diterpenoid isolated from Andrographis paniculata, is developed. After the initial success of this protocol with andrographolide (1) to provide 19-dehydroandrographolide (5) or 3,19-didehydroandrographolide (6) as major products, the procedure was further applied for the oxidation of hydroxyl functionality in andrographolide derivatives, namely 2, 3, 14, and 16. The process was equally suitable on scales of milligram to gram with ease. Deprotection of C-19-OTBDMS in compounds 15 and 18 was achieved using TBDMS-Cl in acetonitrile-water (8:2) system in good yields. 相似文献
72.
A new denudatine-type C20-diterpenoid alkaloid, designated as sinchianine (1), together with eight known diterpenoid alkaloids, 12-acetyl-12-epi-napelline (2), 12-epi-napelline (3), neoline (4), talatisamine (5), 14-O-acetylsenbusine A (6) and benzoylaconine (7), songorine (8) and aconitine (9), were isolated from the whole herb of Aconitum sinchiangense W. T. Wang. Their structures were elucidated on the basis of extensive spectroscopic analyses (NMR and HR-ESI-MS) and comparison with data reported in the literature. 相似文献
73.
Yogesh P. Bharitkar N.S. Apoorva Poduri Anirban Ash Prakas R. Maulik Nirup B. Mondal 《Natural product research》2015,29(3):253-261
Aervalanata possesses various useful medicinal and pharmaceutical activities. Phytochemical investigation of the plant has now led to the isolation of a new 2α,3α,15,16,19-pentahydroxy pimar-8(14)-ene diterpenoid (1) together with 12 other known compounds identified as β-sitosterol (2), β-sitosterol-3-O-β-D-glucoside (3), canthin-6-one (4), 10-hydroxycanthin-6-one (aervine, 5), 10-methoxycanthin-6-one (methylaervine, 6), β-carboline-1-propionic acid (7), 1-O-β-D-glucopyranosyl-(2S,3R,8E)-2-[(2′R)-2-hydroxylpalmitoylamino]-8-octadecene-1,3-diol (8), 1-O-(β-D-glucopyranosyl)-(2S,3S,4R,8Z)-2-[(2′R)-2′-hydroxytetracosanoylamino]-8(Z)-octadene-1,3,4-triol (9), (2S,3S,4R,10E)-2-[(2′R)-2′-hydroxytetracosanoylamino]-10-octadecene-1,3,4-triol (10), 6′-O-(4″-hydroxy-trans-cinnamoyl)-kaempferol-3-O-β-D-glucopyranoside (tribuloside, 11), 3-cinnamoyltribuloside (12) and sulfonoquinovosyldiacylglyceride (13). Among these, six compounds (8–13) are reported for the first time from this plant. Cytotoxicity evaluation of the compounds against five cancer cell lines (CHO, HepG2, HeLa, A-431 and MCF-7) shows promising IC50 values for compounds 4, 6 and 12. 相似文献
74.
The first total synthesis and determination of the absolute configuration of chapecoderin A, B and C
The seco- and rearranged-labdanes, chapecoderins A 1, B 2, and C 3 have been synthesized for the first time starting from (S)-(+)-Wieland-Miescher ketone analogue 11. Their absolute configurations have been determined as depicted in the structures 1, 2 and 3. 相似文献
75.
Two novel diterpenoids were isolated from the bulbs of Fritillaria anhuiensis S. C. Chen and S. E. Yin. Compound 1 was the first diterpenoid containing a sulfonyl group isolated from nature. Compound 2 was a novel kaurane-type diterpenoid. Their structures were determined by extensive spectroscopic analysis (IR, MS, NMR, and X-ray diffraction). Compound 1 significantly attenuated nitric oxide (NO) production of a macrophage cell line of Raw 264.7 cells stimulated with IFN-γ. 相似文献
76.
Mahfuz Elmastas Besir Isnac Huseyin Aksit Ozkan Sen Nusret Genc 《Natural product research》2016,30(3):299-304
Teucrium chamaedrys L. is an aromatic and medicinal plant used as traditional medicine. Aerial parts of the plant material were dried and extracted with hexane–dichloromethane (extract 1), ethyl acetate–dichloromethane (extract 2) and methanol–dichloromethane (extract 3) in a ratio of 1:1 at rt successively. The solvents were evaporated to give crude extracts. Extract 1 was suspended in water at 60°C then partitioned successively with hexane and ethyl acetate to give hexane and ethyl acetate portions. After the column chromatography (silica gel) of ethyl acetate extract, one new and four known compounds were isolated. The new compound was named as 1(12S,18R)-15,16-epoxy-2β,6β-dihydroxy-neo-cleroda-13(16),14-dien-20,l2-olide-l8,l9-hemiacetal (teuchamaedryn D) (4). The known compounds were teucrin A (1), dihydroteugin (2), teucroxide (3), syspirensin A (5). The chromatographic methods were also applied for extract 3 to isolate verbascoside (6) and teucrioside (7). The structure of isolated compounds was elucidated by spectroscopic methods including LC-TOF/MS, 1D NMR and 2D NMR. 相似文献
77.
贵州冬凌草的对映-贝壳杉烷二萜化合物 总被引:3,自引:0,他引:3
从贵州产冬凌草[Isodon rubescens (Hemsl.) Hera]中分离得到12个6,7-断 裂-7,20-内酯-对映-贝壳杉烷二萜化合物,经波谱分析鉴定了它们的结构, 其中有7个新化合物,分别命名为贵州冬凌草乙素~辛素(guidongnins B~H, 1~ 7),以及卢氏冬凌草甲素(8)、卢氏冬凌草乙素(9)、贵州冬凌草素(10)、狭 叶香茶菜素(angustifolin, 11)和6-表香茶菜素(6-epiangustifolin, 12)等5个 已知化合物。另外,将作者原命名的贵州冬凌草素(guidongnin, 10)更名为贵州 冬凌草甲素(guidongnin A, 10),并利用二维核磁区振波谱技术修订了卢氏冬凌草 乙素的结构。 相似文献
78.
The Diterpenoid Quinones from Coleus forskohlii 总被引:4,自引:0,他引:4
Chun Suo YAO Yun Long XU* Laboratory of Phytochemistry Kunming Institute of Botany Academia Sinica Kunming 《中国化学快报》2001,(4)
Coleus forskohlii is only distributed in Yunnan and the southern regions of Asia. The decoction of the plant is used in local folk medicine against asthma, cough and bronchitis. Meanwhile, the plant was developed into a new drug for the treatment of asthma, cough, acute and chronic bronchitis several years ago by our group1. It appears that the Coleus is rich source of diterpenoids with different oxygenation patterns2, and six diterpenoids have been isolated from its whole plant distributed i… 相似文献
79.
V. E. Romanov E. E. Shul’ts M. M. Shakirov G. A. Tolstikov 《Chemistry of Natural Compounds》2008,44(3):346-351
New N-acylates of the norditerpenoid alkaloid N-deacetyllappaconitine that were modified in the aromatic ring and are interesting as potential pharmacologically valuable
compounds were prepared.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 275–279, May–June, 2008. 相似文献
80.
Jian-Fan Sun Hui Huang Xing-Yun ChaiXian-Wen Yang Li MengCai-Guo Huang Xue-Feng ZhouBin Yang Jing HuXian-Qiang Chen Hui LeiLishu Wang Yonghong Liu 《Tetrahedron》2011,67(6):1245-1250
Five new briarane type diterpenoids, dichotellides A−E (1−5), were isolated from the South China Sea gorgonian Dichotella gemmacea together with four known analogues (6−9). Compounds 1−5 represent the first examples of iodine-containing briarane type diterpenoids from nature. The structures of these diterpenoids were elucidated by spectroscopic analysis, including 1D, 2D-NMR, and HRESIMS, and the absolute configuration of 1 was further confirmed by single crystal X-ray diffraction analysis. All the isolates were evaluated for cytotoxicity activity against four human tumor cell lines, and only 3 exhibited marginal activity against SW1990 (human pancreatic cancer). 相似文献