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1.
W. Stcklin 《Helvetica chimica acta》1968,51(6):1235-1242
The structure of gymnestrogenin, a new triterpene from the leaves of Gymnema sylvestre R. Br. (Asclepiadaceae), is proposed to be that of 3β, 16β, 21β, 23, 28-pentahydroxy-olean-12-ene. 相似文献
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Armando Zarrelli Marina DellaGreca Afef Ladhari Rabiaa Haouala Lucio Previtera 《Helvetica chimica acta》2013,96(6):1036-1045
Phytochemical investigation of the aerial parts of Gymnema sylvestre has led to the isolation of seven new triterpenes, six oleane types ( 5, 7 – 11 ) and a new lupane type ( 12 ), and of the six known analogues 1 – 4, 6 , and 13 . The structures and relative configurations of these compounds were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR spectroscopy and mass spectrometry, and by the comparison of their NMR data with those of related compounds. 相似文献
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从红树林内源真菌2526#分离到Sterigmatocystin 总被引:4,自引:0,他引:4
从海洋资源中寻找药物已越来越受到重视 ,已有的研究表明海洋资源有可能成为治疗人类疑难病症和延年益寿药物的丰富源泉[1] 。本研究组在从海洋微生物筛选新药的过程中 ,已发现多种结构奇特而具有强生理活性的化合物[2~ 4 ] 。Sterigmatocystin最早分离自陆生真菌Aspergillusversicolor的代谢产物[5] ,随后人们对其结构、生源合成及药理活性进行了广泛的研究。结果表明 ,sterigmatocystin是细胞毒性更强的化合物AflatoxinB1的生源合成前体。本文报道从采自香港红树Avi… 相似文献
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ShuLinPENG XuMinZHU MingKuiWANG LiShengDING 《中国化学快报》2005,16(2):223-224
A novel oleanane-type triterpenic acid was isolated from the leaves of Gymnema sylvestre (Asclepiadaceae). The structure was characterized as 3β, 16β, 22β, 28-tetrahydroxy- olean-12-en30-oic acid on the basis of spectral evidence, including 1D- and 2D-NMR (HMQC, HMBC,^1H-^1H COSY and NOESY). 相似文献
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The isolation, characterisation, purity control and probable structure of gymnemic acid, the antisaccharine principle of Gymnema sylvestre R. Br. (Asclepiadaceae) has been reported. According to the results, gymnemic acid is the D-glucuronide of a probably new hexahydroxy-δ12-oleanene which has been named gymnemagenin and which is esterified with various combinations of the following five acids: formic, acetic, n-butyric, isovaleric, and tiglic acid. Gymnemic acid is not an absolutely pure substance. It is composed predominantly of gymnemic acid A1, which is accompanied by components having similar properties, especially the gymnemic acids A2, A3 and A4. The difference between these components probably lies in the absence or presence of one of the five named acids. 相似文献
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Armando Zarrelli Afef Ladhari Rabiaa Haouala Giovanni Di Fabio Lucio Previtera Marina DellaGreca 《Helvetica chimica acta》2013,96(12):2200-2206
Phytochemical investigation of the aerial parts of Gymnema sylvestre led to the isolation of two known oleanane‐type triterpenes, 1 and 3 , five new acylated derivatives, 2, 4 , and 5 – 7 , and a new lupane‐type triterpene, 8 . The structures and relative configurations of these compounds were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR spectroscopy and mass spectrometry, and by the comparison of their NMR data with those of related compounds. 相似文献
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Du‐Qiang Luo Hui‐Ying Deng Xiao‐Long Yang Bao‐Zhong Shi Jing‐Ze Zhang 《Helvetica chimica acta》2011,94(6):1041-1047
Three new triterpenoid derivatives, named (15α)‐15‐hydroxysoyasapogenol B ( 1 ), (7β,15α)‐7,15‐dihydroxysoyasapogenol B ( 2 ), and (7β)‐7,29‐dihydroxysoyasapogenol B ( 3 ), were isolated from cultures of the plant endophytic fungus Pestalotiopsis clavispora. Their structures and relative configurations were elucidated by extensive spectroscopic analysis and X‐ray crystallography. 相似文献
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Pestalofones I – K ( 1 – 3 ), three new dimeric meroterpenoids with 2‐(7‐benzoyl‐2,3‐dihydrobenzofuran‐2‐yl)‐1‐phenylethan‐1‐one (in 1 ) and 2‐(7‐benzoyl‐2,3‐dihydrobenzofuran‐2‐yl)‐1‐(3,8‐dioxatricyclo[5.1.0.02,4]oct‐4‐yl)ethan‐1‐one (in 2 and 3 ) skeletons, were isolated from the solid cultures of the plant endophytic fungus Pestalotiopsis fici. The structures of 1 – 3 were elucidated by NMR experiments. Compound 1 was found to be present as a racemic mixture. The absolute configurations of 2 and 3 were deduced by analogy to the previously isolated metabolites pestalofones G and H ( 4 and 5 ) from the same fungus. Biogenetically, compounds 1 – 3 are derived from the same precursors (co‐isolated compounds 9 and 10 ) as the previously isolated compounds 4 – 8 . Compounds 2 and 3 showed weak cytotoxic activities against four human tumor cell lines T24, HeLa, A549, and MCF‐7. 相似文献
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Xiao‐Long Yang Su Zhang Hua‐Jie Zhu Du‐Qiang Luo Xue‐Yan Gao 《Helvetica chimica acta》2011,94(8):1463-1469
Two new sesquiterpenoid esters, pestalotiopins B and C ( 1 and 2 , resp.) related to the eremophilane class, together with one known compound, berkleasmin C ( 3 ), were isolated from the fermentation broth of the plant endophytic fungus Pestalotiopsis photiniae. Their structures and relative configurations were elucidated by extensive spectroscopic analysis including 1D‐ and 2D‐NMR (HSQC, HMBC, and NOESY), and MS experiments. Compound 1 has an interesting lactam structure, and this type of sesquiterpenoid with a lactam structure is reported for the first time. 相似文献
11.
Aspergillus sp., an endophytic fungus isolated from Crassula arborescens, displayed potent inhibitory activity against the seed germination of Arabidopsis thaliana. The bioactivity-guided fractionation of the culture extract of Aspergillus sp. MJ01 led to the isolation of nine compounds, including one previously undescribed furanone, namely aspertamarinoic acid (1), and eight known compounds, (−)-dihydrocanadensolide (2), kojic acid (3), citreoisocoumarin (4), astellolide A (5), astellolide B (6), astellolide G (7), cyclo-N-methylphenylalanyltryptophenyl (8) and (−)-ditryptophenaline (9). In the evaluation of the phytotoxic activities of compounds 1–9, the results suggested that 1 and 5 showed significant inhibitory activity on the seed germination of A. thaliana. This is the first report to disclose the phytotoxic activity of these compounds. 相似文献
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对红树植物海杧果内生真菌Penicillium sp.发酵液的乙酸乙酯提取物进行了柱层析分离, 得到3个化合物, 经MS, NMR, 1H-1H COSY, HMQC和HMBC等鉴定, 分别为4-(3-hydroxybutan-2-yl)-3,6-dimethylbenzene-1,2-diol(1), 4-(3-hydroxybutan-2-yl)-3-methyl-6-acetylbenzene-1,2-diol(2)和3,4,5-trimethyl-1,2-benzenediol(3). 其中化合物1和2为新化合物, 化合物3为新的天然产物. 抗菌活性测试结果表明, 化合物1和3均具有抗耐甲氧西林金黄色葡萄球菌的活性, 化合物2则未显示此活性. 相似文献
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Du‐Qiang Luo Yu‐Peng Chen Jun Zhang Bao‐Zhong Shi Zi‐Qi Yang Chuan Chen 《Helvetica chimica acta》2013,96(2):309-312
A new glycine derivative, podocarpiamide ( 1 ), a new indole alkaloid, 1‐methoxy‐1H‐indol‐3‐ethanol ( 2 ), together with two known compounds, 1‐methoxy‐1H‐indole‐3‐acetic acid ( 3 ) and methyl 1‐methoxy‐1H‐indole‐3‐acetate ( 4 ), were isolated from the fermentation broth of the plant endophytic fungus Pestalotiopsis podocarpi. Their structures were elucidated by extensive spectroscopic analysis including 1D‐ and 2D‐NMR (HSQC, HMBC, and COSY) and MS experiments. Compound 1 has an interesting unusual carbamic acid structure. 相似文献
14.
Jeferson Rodrigo Souza Pina Joo Victor Silva-Silva Josiwander Miranda Carvalho Heriberto Rodrigues Bitencourt Luciano Almeida Watanabe Juan Matheus Pereira Fernandes Guilherme Eduardo de Souza Anna Caroline Campos Aguiar Rafael Victorio Carvalho Guido Fernando Almeida-Souza Ktia da Silva Calabrese Patrícia Santana Barbosa Marinho Andrey Moacir do Rosario Marinho 《Molecules (Basel, Switzerland)》2021,26(11)
The natural compound ravenelin was isolated from the biomass extracts of Exserohilum rostratum fungus, and its antimicrobial, antiplasmodial, and trypanocidal activities were evaluated. Ravenelin was isolated by column chromatography and HPLC and identified by NMR and MS. The susceptibility of Gram-positive and Gram-negative bacteria strains to ravenelin was determined by microbroth dilution assay. Cytotoxicity was evaluated in hepatocarcinoma cells (HepG2) and BALB/c peritoneal macrophages by using MTT. SYBR Green I-based assay was used in the asexual stages of Plasmodium falciparum. Trypanocidal activity was tested against the epimastigote and intracellular amastigote forms of Trypanosoma cruzi. Ravenelin was active against Gram-positive bacteria strains, with emphasis on Bacillus subtilis (MIC value of 7.5 µM). Ravenelin’s antiparasitic activities were assessed against both the epimastigote (IC50 value of 5 ± 1 µM) and the intracellular amastigote forms of T. cruzi (IC50 value of 9 ± 2 µM), as well as against P. falciparum (IC50 value of 3.4 ± 0.4 µM). Ravenelin showed low cytotoxic effects on both HepG2 (CC50 > 50 µM) and peritoneal macrophage (CC50 = 185 ± 1 µM) cells with attractive selectivity for the parasites (SI values > 15). These findings indicate that ravenelin is a natural compound with both antibacterial and antiparasitic activities, and considerable selectivity indexes. Therefore, ravenelin is an attractive candidate for hit-to-lead development. 相似文献
15.
Chemical Constituents of the Endophytic Fungus Phomopsis sp. A240 Isolated from Taxus chinensis var. mairei 下载免费PDF全文
Mei‐Hua Tao Yu‐Chan Chen Xiao‐Yi Wei Jian‐Wen Tan Wei‐Min Zhang 《Helvetica chimica acta》2014,97(3):426-430
A new sesquiterpene, eremophil‐9‐ene‐11,12,13‐triol ( 1 ), a new oxazole, 4‐(2‐hydroxyethyl)‐5‐methyloxazole ( 2 ), and the two known lactones, 5′‐hydroxyalternariol ( 3 ) and alternariol ( 4 ), were isolated from the extract of Phomopsis sp. A240, an endophytic fungus isolated from the bark of Taxus chinensis var. mairei. The structures of the isolated compounds were determined by analyses of their spectroscopic data, as well as by comparison with literature reports. The isolated compounds were evaluated for their cytotoxic and antioxidant activities. 相似文献
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Lívia Soman de Medeiros Michael Murgu Antônia Q. L. de Souza Edson Rodrigues‐Fo. 《Helvetica chimica acta》2011,94(6):1077-1084
Four depsides, all of them new as natural products, were isolated from Cladosporium uredinicola solid‐media culture and identified as 3‐hydroxy‐2,5‐dimethylphenyl 2,4‐dihydroxy‐3,6‐dimethylbenzoate ( 1 ), 3‐hydroxy‐2,4,5‐trimethylphenyl 2,4‐dihydroxy‐3,6‐dimethylbenzoate ( 2 ), 3‐hydroxy‐2,5‐dimethylphenyl 3‐[(2,4‐dihydroxy‐3,6‐dimethylbenzoyl)oxy]‐6‐hydroxy‐2,4‐dimethylbenzoate ( 3 ), and 3‐hydroxy‐2,4,5‐trimethylphenyl 3‐[(2,4‐dihydroxy‐3,6‐dimethylbenzoyl)oxy]‐6‐hydroxy‐2,4‐dimethylbenzoate ( 4 ). The endophytic fungus was isolated from Psidium guajava fruits and cultivated over sterilized rice. The compounds 1 – 4 were purified by classical chromatographic procedures, and the chemical structures were identified by spectroscopic studies, mainly 1D‐ and 2D‐NMR and LC/ESI‐MS/MS. Three of the isolated depsides exhibited moderate bacteriostatic and/or bactericide effects on Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtillis. 相似文献
19.
Isolation and structure elucidation of gymnemic acids, antisweet principles of Gymnema sylvestre. 总被引:5,自引:0,他引:5
The structure of gymnemagenin (3 beta,16 beta,21 beta,22 alpha,23,28-hexahydroxy-olean-12-ene), the sapogenin of the antisweet principles of Gymnema sylvestre, was established by X-ray analysis of the 3 beta,23;21 beta,22 alpha-di-O-isopropylidene derivative. On the basis of this result, the structure of deacylgymnemic acid was elucidated as the 3-O-beta-glucuronide from the carbon-13 nuclear magnetic resonance spectra. Five antisweet principles, gymnemic acid-III, -IV, -V, -VIII, and -IX, were isolated in pure states from the hot water extract of leaves of Gymnema sylvestre. Of these, three (GA-III, -IV, and -V) were known, while two (GA-VIII and -IX) were new compounds. The structures of GA-VIII and -IX were elucidated as 3'-O-beta-D-arabino-2-hexulopyranosyl gymnemic acid-III and -IV, respectively. 相似文献