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1.
Two new megastigmane, cucumegastigmanes I (1) and II (2), together with a known megastigmane, (+)-dehydrovomifoliol (3), and five other known compounds were isolated from the leaves of Cucumis sativus. The structures of the new compounds were elucidated from spectroscopic analysis and their absolute stereochemistries were determined in detail using the chemical conversion and a modified Mosher's method. 相似文献
2.
Four new cholestane glycosides (1-4) were isolated from the leaves of Cordyline terminalis (Agavaceae). The structures of the new compounds were determined on the basis of spectroscopic analysis and a few chemical transformations followed by chromatographic and spectroscopic analyses. 相似文献
3.
Cycloartane glycosides from the rhizomes of Cimicifuga racemosa and their cytotoxic activities 总被引:3,自引:0,他引:3
Phytochemical analysis of the rhizomes of Cimicifuga racemosa (Ranunculaceae) resulted in the isolation of twelve cycloartane glycosides (1--12), including four new ones (4--6, 12). The structures of the new compounds were determined by spectroscopic analysis, including two-dimensional (2D) NMR data, and chemical methods. The isolated compounds were evaluated for their cytotoxic activities against human oral squamous cell carcinoma (HSC-2) cells and normal human gingival fibroblasts (HGF). 相似文献
4.
Coumarin-glycoside and Ferulate from Peucedanum decursivum 总被引:2,自引:0,他引:2
The root of Peucedanum decursivum (Miq.) Maxim (umbelliferae) is known as a famoustraditional Chinese medicine. In our Studies on the chemical constituents, compounds Iand 2 were isolated from the extract of the roots by combination of silica gel columnchromatography and preparative HPLC.Compound l, yellow powder, C,.H,,O., (HRFAB-MS (M-H) - m/z. cafed. 475. 1604.ohs. 475.1594), UV spectrum (X max 334 and 203 "m), IH and 13C NMR spectra werequite similar to those of furocoumarin gl… 相似文献
5.
《Journal of heterocyclic chemistry》2017,54(1):35-43
A new series compounds of quinoline derivatives were synthesized by reaction of 3‐(carboxymethyl)‐2‐arylquinoline‐4‐carboxylic acids 1a , 1b , 1c with different nucleophiles. The structures of the new compounds were elucidated on the basis of FTIR, 1H‐NMR, 13C‐NMR spectral data, GC/MS, and chemical analysis. Investigation of antimicrobial activity of all new compounds was evaluated using a broth dilution technique in terms of minimal inhibitory concentration count against four pathogenic bacteria and two pathogenic fungi. Most of the new compounds were significantly active against bacteria and fungi. 相似文献
6.
Wen Zhang Hui Huang Yu Ding Margherita Gavagnin Ernesto Mollo Guido Cimino Yue‐Wei Guo 《Helvetica chimica acta》2006,89(4):813-820
Three new polyoxygenated steroids, muricesteroid ( 1 ), and menellsteroids A ( 2 ) and B ( 3 ), were isolated from two species of the South China Sea gorgonian Muricella flexuosa and Menella verrucosa Brundin , respectively. The structures of these new compounds were elucidated on the basis of extensive spectroscopic analysis, chemical methods and comparison with known related compounds. 相似文献
7.
Jie Liu Mingxia Wang Lianming Chen Yueting Li Yijun Chen Ziyi Wei Zhixin Jia Wenjuan Xu Hongbin Xiao 《Journal of separation science》2019,42(13):2202-2213
Comprehensive characterization of the large number of compounds existing in traditional Chinese medicines is still a great challenge. In this study, a strategy of precursor ion selected acquisition coupled with target and nontarget data mining was established to systematically characterize the chemical constituents of traditional Chinese medicines. This strategy consisted of four steps: (1) precursor ion selected acquisition was developed to trigger additional tandem mass spectrometry fragmentation reactions, especially for trace constituents; (2) in‐house database of compounds was established and diagnostic characteristics were summarized; (3) compounds were identified by target and nontarget data mining; and (4) compound structures were elucidated based on accurate mass matching and comparison of fragment ions, and isomers were discriminated by the intensity of fragment ions, fragmentation pattern analysis, and calculated log P values. This strategy was successfully applied to comprehensively identify the constituents in Dachuanxiong decoction. Finally, a total of 218 compounds assigned to six categories were characterized, and 107 compounds were characterized by nontarget analysis for the first time. In addition, three new diagnostic characteristics of esters of citric acids were elucidated. This research enriched the material basis of Dachuanxiong decoction and provided a new strategy for identifying the chemical constituents of other traditional Chinese medicines. 相似文献
8.
Aoki S Ye Y Higuchi K Takashima A Tanaka Y Kitagawa I Kobayashi M 《Chemical & pharmaceutical bulletin》2001,49(10):1372-1374
Two novel aplysinopsin-type indole alkaloids, 1 and 2, and three known indole alkaloids were isolated from the marine sponge Hyrtios erecta. These compounds exhibited selective inhibitory activity against the neuronal isozyme of nitric oxide synthase (nNOS). Furthermore, new quinolone 7 was also isolated from the same marine sponge. The chemical structures of these new compounds were elucidated on the basis of spectroscopic analysis. 相似文献
9.
Qihao Wu Song‐Wei Li Heng Xu Hong Wang Pei Hu Hao Zhang Cheng Luo Kai‐Xian Chen Bastien Nay Yue‐Wei Guo Xu‐Wen Li 《Angewandte Chemie (International ed. in English)》2020,59(29):12105-12112
Placobranchus ocellatus is well known to produce diverse and complex γ‐pyrone polypropionates. In this study, the chemical investigation of P. ocellatus from the South China Sea led to the discovery and identification of ocellatusones A–D, a series of racemic non‐γ‐pyrone polyketides with novel skeletons, characterized by a bicyclo[3.2.1]octane ( 1 , 2 ), a bicyclo[3.3.1]nonane ( 3 ) or a mesitylene‐substituted dimethylfuran‐3(2H)‐one core ( 4 ). Extensive spectroscopic analysis, quantum chemical computation, chemical synthesis, and/or X‐ray diffraction analysis were used to determine the structure and absolute configuration of the new compounds, including each enantiomer of racemic compounds 1 – 4 after chiral HPLC resolution. An array of new and diversity‐generating rearrangements is proposed to explain the biosynthesis of these unusual compounds based on careful structural analysis and comparison with six known co‐occurring γ‐pyrones ( 5 – 10 ). Furthermore, the successful biomimetic semisynthesis of ocellatusone A ( 1 ) confirmed the proposed rearrangement through an unprecedented acid induced cascade reaction. 相似文献
10.
Viviane Nadège Nenkep~a Jovita Chi Shirri~a Hanh Trinh Van-Dufat~b Falindor Sipepnou~a Philippe Vérité~d Elisabeth Seguin~c Francois Tillequin~b Jean Wandji~ 《中国化学快报》2008,19(8):943-946
Two new compounds 7-hydroxy-5-O-(β-D-glucopyranoside) flavan (1) and (Z)-4',6'-dihydroxy-2'-O-(β-D-glucopyranoside) chalcone (2), along with eight known compounds, were isolated from the stem bark of Drypetes parvifolia (Euphorbiaceae). Their structures were established on the basis of spectroscopic analysis and chemical evidence. 相似文献
11.
Panpan Zhang Jing Li Jiajia Lang Chunxiu Jia Shah-Iram Niaz 《Natural product research》2018,32(19):2297-2303
Two new sesquiterpenes, leptoterpenes A (1) and B (2) were isolated from the fungus Leptosphaerulina Chartarum sp. 3608, derived from a crinoid. It was the first chemical study on this species. The structures of these compounds were elucidated by spectroscopic methods including NMR and MS spectrometry. The absolute configurations of the new compounds were determined on the basis of the single-crystal X-ray diffraction and electronic circular dichroism data analysis. All compounds were tested for their anti-inflammatory activity and the inhibitory effects on Tyrosyl DNA phosphodiesterase II (TDP2). 相似文献
12.
Synthesis and characterization of ciprofloxacin compounds with cadmium(II) and mercury(II) chlorides
N. N. Golovenv S. D. Kirik I. I. Goloveneva M. E. Nishnevich 《Russian Journal of Inorganic Chemistry》2006,51(3):415-420
Five new compounds of ciprofloxacin (CfH = C17H18FN3O3) with cadmium(II) and mercury(II) chlorides were synthesized. The compounds were characterized by chemical analysis, powder X-ray diffraction, pH-metric titration, UV spectroscopy, and thermal analysis. 相似文献
13.
Li Z Lee DK Coulter M Rodriguez LN Gordon RG 《Dalton transactions (Cambridge, England : 2003)》2008,(19):2592-2597
Three new volatile cobalt amidinate compounds were prepared: Co(tBuNC(R)NEt)2, R=Me, Et and n-Bu. They were characterized by elemental analysis, 1H NMR, X-ray structure analysis, melting point, vapor pressure, vaporization rate, thermal stability and chemical reactivity. They were found to evaporate cleanly without decomposition. Two of them are liquids at room temperature, allowing for more convenient preparation, handling and purification by distillation. They are highly reactive compounds that have been found to be suitable precursors for vapor deposition of cobalt metal, cobalt nitride and cobalt oxide. A new synthetic method allows for the facile and inexpensive preparation of large quantities of these compounds. 相似文献
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15.
Two new lignans were isolated from Phoebe minutiflora, namely 8'-epiaristotetralone (1) and 8'-epiaristoligone (2), together with seven known compounds. Their structures and absolute stereochemistry were determined by spectral analysis (NMR and CD) and chemical correlation. 相似文献
16.
Chang CI Chen WC Shao YY Yeh GR Yang NS Chiang W Kuo YH 《Natural product research》2008,22(13):1158-1162
From the bark of Juniperus chinensis Linn., a new labdane-type diterpene, methyl 14,15-dihydroxy-8(17),12E-labdadien-19-oate (1a), together with nine known compounds, trans-communic acid, cis-communic acid, 15,16-bisnor-13-oxo-8(17),11E-labdadien-19-oic acid, sandaracopimaric acid, 7-oxosandaracopimaric acid, sugiol, 7-oxototarol, alpha-cedrol and beta-sitosteryl-1-O-beta-glucopyranoside were isolated. The structures of those compounds were elucidated based on spectral analysis and chemical evidences. 相似文献
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18.
Four new naphthohydroquinones, rubinaphthins A (1), B (2), C (3), and D (4), together with 11 known compounds were isolated and characterized from the roots of Rubia yunnanensis. The structures of 1-4 were elucidated by spectral analysis and chemical transformation. 相似文献
19.
Two new phenolic amides, pharnilatins A (1) and B (2), were isolated from the seeds of Pharbitis nil. These new compounds possess a p-coumaroyl unit with a structurally unique side chain, (2S,3S)-2,3-dihydroxyputrescine. The chemical structures and absolute stereochemistries of the new compounds were determined on the basis of spectroscopic analyses including 1D- and 2D-NMR experiments and chemical reactions. Compounds 1 and 2 exhibited cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT-15 human tumor cells. However, none of the compounds inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-activated microglia cells. 相似文献
20.
Aigialomycins A-E, new resorcylic macrolides from the marine mangrove fungus Aigialus parvus 总被引:4,自引:0,他引:4
Isaka M Suyarnsestakorn C Tanticharoen M Kongsaeree P Thebtaranonth Y 《The Journal of organic chemistry》2002,67(5):1561-1566
Aigialomycins A-E (2-6), new 14-membered resorcylic macrolides, were isolated together with a known hypothemycin (1) from the mangrove fungus, Aigialus parvus BCC 5311. Structures of these compounds, including absolute configuration, were elucidated by spectroscopic methods, chemical conversions, and X-ray crystallographic analysis. Hypothemycin and aigialomycin D (5) exhibited in vitro antimalarial activity with IC(50) values of 2.2 and 6.6 microg/mL, respectively, while other analogues were inactive. Cytotoxicities of these compounds were also evaluated. 相似文献