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1.
Seven novel polyketides, namely, 1‐(xylarenone A)xylariate A ( 1 ), xylarioic acid B ( 2 ), xylariolide A ( 3 ), xylariolide B ( 4 ), xylariolide C ( 5 ), methyl xylariate C ( 6 ), and xylariolide D ( 7 ), together with the known one taiwapyrone ( 8 ), were isolated from the endophytic fungal strain Xylaria sp. NCY2 of Torreya jackii Chun . Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments, and on the basis of HR‐Q‐TOF mass spectrometry. Antitumor and antibacterial assays of compounds 1 – 8 were carried out, which show moderate activities.  相似文献   

2.
Three new C19‐diterpenoid alkaloids, named aconitramines A ( 1 ), B ( 2 ), and C ( 3 ), were isolated from Aconitum transsectum. By UV, IR, 1D‐ and 2D‐NMR, and MS analyses, their structures were elucidated as 18‐methoxyvilmoraconitine, 18‐demethoxydolichotine A, and 18‐demethoxydolichotine B. Compound 1 is the second known C19‐diterpenoid alkaloid with a three‐membered ring formed by C(8), C(9), and C(10).  相似文献   

3.
Three new monoterpene alkaloids, mairine A ( 1 ), mairine B ( 2 ), and mairine C ( 3 ), and a new caffeic acid ester, 2‐(1‐hydroxy‐4,4‐dimethoxycyclohexyl)ethyl caffeate ( 4 ), were isolated from the EtOH extract of the whole plants of Incarvillea mairei var. multifoliolata. The structures of these compounds were established on the basis of 1D‐ and 2D‐NMR and HR‐ESI‐MS analysis.  相似文献   

4.
Eleven new indole alkaloids were isolated from cultures of the human pathogenic yeast Malassezia furfur after addition of L ‐tryptophan as the sole N‐source: pityriacitrin B ( 2 ), the malassezindoles A ( 3 ) and B ( 4 ), malassezialactic acid ( 6 ), the malasseziazoles A ( 7 ), B ( 8 ), and C ( 9 ), pityriazole ( 10 ), malasseziacitrin ( 11 ), and malassezione ( 12 ), along with the known d‐ indole‐3‐lactic acid (=(αR)‐α‐hydroxy‐1H‐indole‐3‐propanoic acid 5 ), and 2‐hydroxy‐1‐(1H‐indol‐3‐yl)ethanone ( 13 ). The structural elucidation of these compounds was performed by spectroscopic methods (MS as well as 1D‐ and 2D‐NMR). The biogenetic relationships (Scheme) and biological activities of the new metabolites are discussed.  相似文献   

5.
Two new daphniphyllum alkaloids named 2‐hydroxyyunnandaphnine D ( 1 ) and methyl 7‐hydroxyhomodaphniphyllate ( 2 ), together with eight known alkaloids, daphnioldhanin D, calyciphylline F, calyciphylline B, deoxycalyciphylline B, daphnicyclidin H, macropodumine C, 9,10‐epoxycalycine A, and yunnandaphnine A, were isolated from the stems and leaves of Daphniphyllum calycinum. Their structures and relative configurations were established on the basis of spectral evidence (including 2D‐NMR) and subsequently confirmed by a single‐crystal X‐ray crystallographic diffraction analysis.  相似文献   

6.
Five new quassinoids, named picraqualides A–E ( 1 – 5 ), together with eleven known ones, nigakilactone E ( 6 ), nigakilactone F ( 7 ), kusulactone ( 8 ), javanicin U ( 9 ), 12‐norquassin ( 10 ), quassin ( 11 ), 2,3‐didehydropicrasin B ( 12 ), nigakilactone B ( 13 ), nigakilactone C ( 14 ), picrasin B ( 15 ), and simalikalacton C ( 16 ), were isolated from the EtOH extract of the bark of Picrasma quassioides (D. Don ) Benn . Their structures were determined mainly by spectroscopic methods, especially by 2D‐NMR techniques and circular dichroism (CD). Some empirical rules were summarized on the basis of 13C‐NMR spectral analysis to distinguish between OH (or Ac) groups attached at C(11) vs. C(13).  相似文献   

7.
Four new pregnane‐type steroids, krempenes A–D ( 1 – 4 ), were isolated from the marine soft coral Cladiella krempfi. Their structures were elucidated on the basis of 1D‐ and 2D‐NMR analyses, as well as MS experiments. Krempene A ( 1 ) contains a very unusual structural motif, with a hexacyclic oxadithiino unit fused to the steroidal ring A. Krempene B ( 2 ) is a 19‐norpregnane steroid, the 19‐Me group formally being transferred to position 4. Furthermore, krempene D contains an unusual C?C bond at C(7) of the pregnane skeleton.  相似文献   

8.
A new dimeric coumarin, diseselin B ( 1 ), and three new phenylpropanoids, lenisin A–C ( 2 – 4 ), together with eight known O‐terpenoidal coumarins, were isolated from the aerial part of Clausena lenis. Lenisin A ( 2 ) was also isolated from the aerial part of C. excavata. The structures were elucidated on the basis of 1D‐ and 2D‐NMR experiments (HMQC, HMBC, and 1H,1H‐COSY).  相似文献   

9.
One novel p‐terphenyl compound, named vialisyl A ( 1 ), was isolated from the fruiting bodies of Thelephora vialis, together with six known compounds, ganbajunin B ( 2 ), phenylacetic acid ( 3 ), a mixture of ganbajunins D ( 4 ) and E ( 5 ), and vialinins A ( 6 ) and B ( 7 ). Their structures were established by extensive analysis of spectroscopic data (including 1H‐ and 13C‐NMR, HSQC, HMBC, 2D‐INADEQUATE) as well as by comparison with literature reports.  相似文献   

10.
Photosensitization mechanisms in photopolymer coating film containing an aminochalcone‐type dye sensitizer and a radical generating reagent, sensitizer dyes, (E)‐3‐(9‐julolidinyl)‐1‐phenyl‐2‐propen‐1‐one (A), (E)‐2‐(9‐julolidinyl)‐methylene‐1‐indanone (B), 9‐benzoyl‐2,3,6,7‐tetrahydro‐1H,5H‐benzo[i,j]‐furano‐[3,2‐g]quinolizine (C), 4‐(dimethylamino) chalcone (D) and a radical‐generating reagent, 2,4,6‐tris (trichloromethyl)‐1,3,5‐triazine (TCT), were investigated by laser flash photolysis using a total reflection cell. Weak fluorescence and strong broad triplet absorption were detected. The fluorescence was statically quenched by TCT at quenching distances (Rf) of 15, 14, 20 and 14 Å for A, B, C and D as well as the triplet initial absorption, at quenching distances (Rt) of 16, 16, 16 and 14 for A, B, C and D, similar to the fluorescence quenching distances. The triplet decay time of the dyes was inefficiently quenched by TCT with the rate constants (k q) of 1.9, 3.1, 0.7 and 1.0×105 mol−1/dm3/s for A, B, C and D. The sensitivity of photopolymers containing a sensitizer dye and a TCT was obtained at an excitation of 488 nm corresponding to the emission peaks of argon ion laser of 1.1, 0.2, 0.54 and 9.1 mJ cm2 for A, B, C and D. The results indicated that the static sensitization process from the fluorescent singlet excited state of the dyes to the ground state of TCT was predominant, and the high sensitivity for A and B was caused by the high absorbance at 488 nm and that for C by the high fluorescent quenching distance. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

11.
Phytochemical investigation of the medicinal plant Isodon phyllostachys led to the isolation of four new ent‐kaurane diterpenoids, phyllostacins F–I ( 1 – 4 , resp.), together with 11 known compounds, rosthorin A ( 5 ), rabdoternin C ( 6 ), enmenol ( 7 ), oridonin ( 8 ), lasiocarpanin ( 9 ), xerophilusin B ( 10 ), ponicidin ( 11 ), macrocalin B ( 12 ), phyllostachysin A ( 13 ), sculponeatin C ( 14 ), and macrocalyxoformin E ( 15 ). The structures of the new compounds were established by spectroscopic methods, including extensive 1D‐ and 2D‐NMR analyses. Compounds 1, 2, 7, 10 , and 13 were evaluated for their inhibitory activity against K562 and HepG2 cell lines.  相似文献   

12.
Two new perulactone‐type withanolides, named perulactone C ( 1 ) and perulactone D ( 2 ), together with four known compounds, perulactone ( 3 ), perulactone B ( 4 ), blumenol A, and (+)‐(S)‐dehydrovomifoliol, were isolated from the aerial parts of Physalis peruviana. The structures of the new compounds were elucidated on the basis of 1D‐ and 2D‐NMR experiments, including HMBC, HSQC, 1H,1H‐COSY, and ROESY, as well as HR‐MS.  相似文献   

13.
Sampsone A ( 1 ), a novel prenylated aromatic lactone, and sampsone B ( 2 ), an unusual dihydrodibenzodioxinone, together with sampsone C ( 3 ), a new xanthone, were isolated from the aerial parts of Hypericum sampsonii. Their structures were determined by spectroscopic methods which were mainly 1D‐ and 2D‐NMR techniques, and the structure of sampsone B ( 2 ) was also confirmed by X‐ray crystallographic analysis. All of these compounds were evaluated for in vitro antibacterial activity against methicillin‐resistant Staphylococcus aureus (MRSA). Only sampsone A showed moderate antibacterial activities at a minimum inhibitory concentration (MIC) of 32 μg/ml.  相似文献   

14.
Four novel diterpenoids, namely (4β)‐4,4‐O‐dihydrocrinipellin A ( 1 ), (4β,8α)‐4,4‐O,8,8‐O‐tetrahydrocrinipellin B ( 2 ), crinipellin C ( 3 ), and crinipellin D ( 4 ), along with three known ones, (3β,4β)‐3,3‐C,4,4‐O‐tetrahydrocrinipellin A ( 5 ), (4β)‐4,4‐O‐dihydrocrinipellin B ( 6 ), and phlebiakauranol alcohol, were isolated from the fungal strain Crinipellis sp. 113. Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments, and by HR‐Q‐TOF mass spectrometry. Antitumor and antibacterial assays with the novel compounds 1 – 4 were carried out, showing moderate activities against HeLa cells and no effects on the growth of tested bacteria or yeast.  相似文献   

15.
从人面果乙酸乙酯提取物中分离出5个新的口 山 酮 化合物garcinenone A (1), B (3), C (4), D (7) and E (8)和7个已知化合物,其结构经过波谱技术,特别是2D-NMR技术来鉴定。Jacareubin (2), 1,4,6-trihydroxy-5-methoxy-7-(3-methyl-2-buteny1)xanthone (6), subeliptenone B (11) 和symphoxanthone (12)为首次从该植物中分离出来。在DPPH自由基的清除活性实验中,所有的化合物都显示抗氧化活性,其IC50的值在 6.0-23.2 mM。结果表明人面果是潜在的有前景的天然抗氧化剂。  相似文献   

16.
Two new biflavonoids, 14″‐O‐methyldihydrodaphnodorin B ( 1 ) and 14″‐O‐methyldaphnodorin J ( 2 ), along with 16 known compounds, i.e., dihydrodaphnodorin B ( 3 ), daphnodorin J ( 4 ), 3″‐epidihydrodaphnodorin B ( 5 ), daphnodorin B ( 6 ), neochamaejasmin B ( 7 ), sikokianin B ( 8 ), (?)‐syringaresinol ( 9 ), (?)‐syringaresinol 4‐Oβ‐D ‐glucopyranoside ( 10 ), (+)‐nortrachelogenin ( 11 ), (?)‐lariciresinol ( 12 ), (?)‐pinoresinol ( 13 ), syringin ( 14 ), syringinoside ( 15 ), daphnoretin ( 16 ), phorbol 13‐acetate ( 17 ), and methyl paraben ( 18 ) were isolated from the roots of Diplomorpha canescens (Meisn.) C.A. Meyer . The structures were determined on the basis of spectroscopic data.  相似文献   

17.
Three novel pentacyclic triterpenoid dienolides, phyllenolide A (=3β‐acetoxyglutina‐5(10), 6‐dien‐27,8α‐olide; 1 ), phyllenolide B (=3β‐(benzoyloxy)glutina‐5(10),6‐dien‐27,8α‐olide; 2 ), and phyllenolide C (=3β‐(2‐hydroxybenzoyloxy)glutina‐5(10),6‐dien‐27,8α‐olide; 3 ), were isolated from the aerial parts of Phyllanthus myrtifolius Moon . (Euphorbiaceae). These three compounds possess an endocyclic γ‐lactone moiety across ring C and a homo‐annular diene system in ring B. Their structures were established by analyses of CD, NOED, and 2D‐NMR spectra.  相似文献   

18.
From the roots of three species of Acanthophyllum (Caryophyllaceae), two new gypsogenic acid glycosides, 1 and 2, were isolated, 1 from A. sordidum and A. lilacinum, 2 from A. elatius and A. lilacinum, together with three known saponins, glandulosides B and C, and SAPO50. The structures of 1 and 2 were established mainly by 2D NMR techniques as 23‐O‐β‐D ‐galactopyranosylgypsogenic acid‐28‐O‐β‐D ‐glucopyranosyl‐(1→3)‐[β‐D ‐glucopyranosyl‐(1→6)]‐β‐D ‐galactopyranoside (1) and gypsogenic acid‐28‐O‐β‐D ‐glucopyranosyl‐(1→3)‐[β‐D ‐glucopyranosyl‐(1→6)]‐β‐D ‐galactopyranoside (2). The cytotoxicity of several of these saponins was evaluated against two human colon cancer cell lines (HT‐29 and HCT 116). Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

19.
Two new tricyclic sesterterpenes, fusaprolifins A and B ( 1 and 2 ), and three new 2H‐pyran‐2‐one derivatives, prolipyrones A – C ( 3 – 5 ), were isolated and characterized from Fusarium proliferatum MA‐84, an endophytic fungus obtained from the fresh tissue of the marine mangrove plant Bruguiera sexangula. In addition, two known sesterterpenes, terpestacin ( 6 ) and fusaproliferin ( 7 ), and one known 2H‐pyran‐2‐one derivative, gibepyrone D ( 8 ), were also identified. The structures of these compounds were elucidated by detailed spectroscopic analyses. Fusaprolifin A ( 1 ) showed moderate activity against brine shrimp (Artemia salina), with a lethality rate of 49.5% at 100 μg/ml, while fusaprolifin B ( 2 ) showed weak activity.  相似文献   

20.
Four new benzofuran derivatives were isolated from the roots of Ligularia stenocephala; they were named as ligustenin A ( 1 ), B ( 2 ), C ( 3 ) and D ( 4 ), and the structures were established by spectroscopic methods including 2D NMR techniques. Ligustenin A (1) was found to exhibit potent anti‐tumor activity against HL‐60 (human leukemia cells), Bel‐7402 (human hepatoma cells) and HO‐8910 (human ovarian neoplasm cells) with IC50 values of 18.6, 27.6 and 57.5 μM, respectively.  相似文献   

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