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1.
《Magnetic resonance in chemistry : MRC》2003,41(2):145-146
A new prenylated benzopyrancarboxylic acid, 1a (3,4‐dihydro‐5‐hydroxy‐2,7‐dimethyl‐8‐(2‐methyl‐2‐butenyl)‐ 2‐(4‐methyl‐1, 3‐pentadienyl)‐2H‐1‐benzopyran‐6‐carboxylic acid) was isolated from Peperomia amplexicaulis and fully characterized by 1D and 2D NMR and high‐resolution mass spectrometry. In the course of this investigation, the structure of a related compound (minus the carboxylic acid group) which was previously assigned as 2b was corrected to structure 1b . Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
2.
Liuyuan Chen Yinghui Duan Chang Li Yu Wang Xupeng Tong Yi Dai Xinsheng Yao 《Magnetic resonance in chemistry : MRC》2013,51(12):842-846
Four new prenylated flavonoids, cudraflavanones E‐F (1–2) and cudraflavones F‐G (6–7), together with eight known compounds were isolated from the roots of Cudrania tricuspidata. The structures of new compounds were elucidated on the basis of extensive spectroscopic analyses, including 1D and 2D NMR, HRESIMS and CD. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
3.
M. Concepción Lozada Simón Hernández‐Ortega María Luisa Villarreal Dino Gnecco Raúl G. Enríquez William Reynolds 《Magnetic resonance in chemistry : MRC》2012,50(1):52-57
From the stem bark of Mangifera indica, seven cycloartane‐type secondary metabolites were isolated. Compound 1 has been isolated for the first time from M. indica, whereas compounds 2 (2a and 2b, as an epimeric mixture), 3, and 4 are new triterpenoid‐type cycloartanes. Unambiguous 13C and 1H NMR assignments for these compounds and the known compounds mangiferonic acid (compound 5), isomangiferolic acid (compound 6), ambolic acid (compound 7), and friedelin (compound 8) are reported; the latter because full NMR data for these compounds are not available in the literature. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
4.
Xiu Lan Xin Guowei Yang Zhan Ping Gou Ji Hong Yao Rong Lan Xiao Chi Ma 《Magnetic resonance in chemistry : MRC》2010,48(2):164-167
Five hydroxylated derivatives of glycyrrhetinic acid by Mucor polymorphosporus were isolated. Among them, 6β, 7β‐dihydroxyglycyrrhentic acid (2) and 27‐hydroxyglycyrrhentic acid (3) are new compounds. Their chemical structures were identified by spectral methods including 2D‐NMR. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
5.
Cheng‐Xiong Liu Zhi‐yong Guo Yan‐Hong Xue Hong‐Yan Zhang Hong‐Qi Zhang Kun Zou Nian‐Yu Huang 《Magnetic resonance in chemistry : MRC》2012,50(4):320-324
Three new steroidal compounds with polyhydroxy groups, tupisteroide A–C (1–3), were obtained from the roots of Tupistra chinensis, together with one known compound (4) that was isolated from this plant for the first time. The structures of tupisteroide A–C were determined on the basis of one‐ and two‐dimensional NMR spectroscopy, including 1H–1H Correlation Spectroscopy, Heteronuclear Multiple Bond Correlation, and Heteronuclear Single Quantum Coherence experiments. The isolated compounds were evaluated for their cytotoxic activities against A549, HepG2, and CaSki cancer cell lines in vitro. Among them, compounds 1, 2, and 4 did not show significant inhibitory activity, but compound 3 showed cytotoxicity against A549 cancer cell lines with IC50 values of 25.0 μM. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
6.
Fazuo Wang Tianjiao Zhu Min Zhang Aiqun Lin Weiming Zhu Qianqun Gu 《Magnetic resonance in chemistry : MRC》2010,48(2):155-158
Three new furan and pyran derivatives named aspericins A? C (1–3), as well as a known asperic acid (4), have been isolated from the marine‐derived fungus Rhizopus sp. 2‐PDA‐61. The complete 1H and 13C NMR assignments for the new compounds were carried out using 1H, 13C, DEPT, COSY, HMQC, HMBC, and NOESY NMR experiments. Compounds 1–3 were evaluated for their cytotoxic activities on P388, A549, HL‐60, and BEL‐7420 cell lines by the MTT and SRB methods. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
7.
《Magnetic resonance in chemistry : MRC》2018,56(1):18-24
Halotolerant fungus Cladosporium cladosporioides OUCMDZ‐187 was isolated from the mangrove plant Rhizophora stylosa collected in Shankou, Guangxi Province of China. Three new fatty acid esters cladosporesters A–C ( 1 – 3 ) and 5 new fatty acids cladosporacids A–E ( 4 – 8 ) were isolated from the ethyl acetate extract of the fermentation broth of OUCMDZ‐187 in a hypersaline (10% salt) medium. Their structures were elucidated by UV, IR, MS, specific rotation, and 1D and 2D NMR data. 相似文献
8.
Zhang‐Gui Ding Jiang‐Yuan Zhao Pei‐Wen Yang Ming‐Gang Li Rong Huang Xiao‐Long Cui Meng‐Liang Wen 《Magnetic resonance in chemistry : MRC》2009,47(4):366-370
An unprecedented new natural product named nocarsin A (1), 5H‐4a,6,7a‐triazacyclopenta[cd]indene‐5,7(6H)‐dione (1), together with seven known compounds lumichrome (2), cyclo (L ‐Leu‐L ‐Tyr) (3), cyclo (L ‐Ala‐L ‐Ile) (4), cyclo (L ‐Ala‐L ‐Leu) (5), cyclo (L ‐Val‐L ‐Ala) (6), 5‐methyluracil (7) and uracil (8), was isolated from Nocardia alba sp.nov (YIM 30243T), which was isolated from a soil sample collected from Yunnan Province, P. R. China. NMR techniques including COSY, HSQC, ROESY, and HMBC were used to elucidate the structures of these compounds. We report the unambiguous assignments of the 1H and 13C NMR spectra of the new compound nocarsin A (1). Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
9.
Amarendra Patra Sumana Ghosh Biswapati Mukherjee 《Magnetic resonance in chemistry : MRC》2010,48(10):823-828
Besides three known biphenyldibenzodioxinbisbenzylisoquinoline alkaloids, two novel alkaloids of the same group have been isolated from the fruits of Tiliacora racemosa. The structures of these new compounds designated tiliaimine and nordinklacorine were established on the basis of 1D and 2D NMR spectroscopy, including COSY, TOCSY, ROESY, HMBC and HSQC experiments. Preliminary antibacterial activity studies on the known compounds (tiliarine, 2′‐nortiliacorinine, 2′‐nortiliacorine) from the fruits of the plant showed strong activity against three bacterial strains viz. Escherichia coli strain VT3 (Verotoxigenic E.coli), Staphylococcus aureus ATCC 25923 and Bacillus subtilis ATCC 6623 but were inactive against the strains Vibrio cholerae O1 (NB2) and Pseudomonas aeruginosa ATCC 15442. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
10.
Jaécio Carlos Diniz Francisco Arnaldo Viana Odaci Fernandes Oliveira Maria Aparecida M. Maciel Maria da Conceição de Menezes Torres Raimundo Braz‐Filho Edilberto R. Silveira Otília Deusdênia L. Pessoa 《Magnetic resonance in chemistry : MRC》2009,47(2):190-193
From the roots of Cordia leucocephala (Boraginaceae), two new meroterpenoid naphthoquinones, 6‐[10‐(12,12‐dimethyl‐13α‐hydroxy‐16‐methenyl‐cyclohexyl)ethyl]‐1,4‐naphthalenedione (cordiaquinone L) and 5‐methyl‐6‐[10‐(12,12‐dimethyl‐13β‐hydroxy‐16‐methenyl‐cyclohexyl)methyl‐1,4‐naphthalenedione (cordiaquinone M) were isolated. Their structures were elucidated after detailed 1D and 2D NMR (COSY, HSQC, HMBC and NOESY) data analyses and comparison with literature data for analogous compounds. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
11.
Bakhat Ali Muhammad Imran Riaz Hussain Zaheer Ahmed Abdul Malik 《Magnetic resonance in chemistry : MRC》2010,48(2):159-163
Two new flavonoids, abutilin A and B, were isolated from the chloroform soluble fraction of Abutilon pakistanicum and their structures assigned from 1H and 13C NMR spectra, DEPT and by 2D COSY, HMQC and HMBC experiments. Ferulic acid (3), (E)‐cinnamic acid (4), 5‐hydroxy‐4′,6,7,8‐tetramethoxyflavone (5), kaempferol (6), luteolin (7) and luteolin 7‐O‐β‐D ‐glucopyranoside (8) have also been reported from this species. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
12.
Yan Xu Hong‐Wu Zhang Xiao‐Chun Wan Zhong‐Mei Zou 《Magnetic resonance in chemistry : MRC》2009,47(6):527-531
Two new sesquiterpenes, epi‐guaidiol A (1) and sugebiol (3), together with four known sesquiterpenes, guaidiol A(2), sugetriol triacetate (4), cyperenoic acid (5), and cyperotundone (6) were isolated from the rhizomes of Cyperus rotundus L. Their structures were identified by MS and NMR experiments, and the complete assignments of 1H and 13C NMR data for two new sesquiterpenes were obtained by the aid of two‐dimensional (2D) NMR techniques, including HSQC, HMBC, 1H‐1HCOSY and nuclear overhauser enhancement spectroscopy(NOESY). Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
13.
Zhongjing Huang Ruiyun Yang Xianhong Yin Zhigang She Yongcheng Lin 《Magnetic resonance in chemistry : MRC》2010,48(1):80-82
The structure elucidations and complete 1H and 13C NMR assignments are reported for two new xanthone derivatives: 1,7‐dihydroxy‐2‐methoxy‐3‐(3‐methylbut‐2‐enyl)‐9H‐xanthen‐9‐one (1) and 1‐hydroxy‐4,7‐dimethoxy‐6‐(3‐oxobutyl)‐9H‐xanthen‐9‐one (2). Both of these secondary metabolites were isolated from the fermentation medium of a mangrove endophytic fungus (No. ZH19). High‐resolution electron impact mass spectrometry (HREIMS), Fourier transform infrared (FT‐IR) absorption spectrometry, and NMR experiments including gCOSY, gHMQC, and gHMBC were used for the determination of the structures and NMR spectral assignments. Preliminary pharmacological test showed that compounds (1) and (2) inhibited KB cells with IC50 values of 20 and 35 µmol/ml, and KBV200 cells with IC50 values of 30 and 41 µmol/ml, respectively. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
14.
N. F. Al-Tannak Ibrahim Khadra N. P. Igoli J. O. Igoli 《Natural product research》2020,34(9):1227-1232
AbstractSeeds of Monodora myristica and M. tenuifolia were extracted with hexane and the extracts were subjected to column chromatography, LC-MS and NMR analysis. In addition to masses of previously isolated compounds, other masses corresponding to unidentified compounds from the plants were detected. Using 2?D NMR techniques, one of the fractions from M. tenuifolia was characterised as a novel 13-(2-butylcyclopropyl)-6,9-dodecadienoic acid. However, none of the compounds detected in LC-MS corresponded to the ones previously identified by GC-MS. 相似文献
15.
A new four-step synthesis of 3,4- and 3,6-dihydro-2H-thiopran-1,1-dioxides from dihydro-2H-thiopyran-3(4H)-one is reported. The title compounds are synthesized starting with oxidation of the ketone with a 30% aqueous solution of hydrogen peroxide in a mixture of AcOH-Ac2O. The keto group is then reduced by sodium borohydride followed by mesylation and elimination of methanesulfonic acid under basic conditions (pyridine for 3,4-isomer and aqueous NaOH for 3,6-isomer). This sequence is simpler, than previously known methods, uses cheaper and more readily available reagents, and leads to 2H-thiopran-1,1-dioxides on multigram scale with 64% and 74% total yields, respectively. The structure and purity of the compounds were confirmed by 2D NMR and GCMS methods. The proposed method expands the means to access functionalized cyclic sulfones as building blocks in the synthesis of combinatorial libraries of new biologically active compounds. 相似文献
16.
《Magnetic resonance in chemistry : MRC》2003,41(2):147-151
Unambiguous and complete assignments of 1H and 13C NMR chemical shifts for three structurally complex labadane diterpenoids isolated from Leonotis ocymifolia (leonotin, leonotinin and nepetaefolin) and six other related compounds (hispanolone, 7α‐ and 7β‐hispanols, marrubiin, villenol and andalusol), previously isolated from Labiatae species, are presented. The assignments are based on 2D shift‐correlated [1H, 1H‐COSY, 1H, 13C‐gHSQC–1J(C,H), 1H,13C‐gHMBC–nJ(C,H) (n = 2 and 3)] and DPFGSE 1D‐NOE experiments. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
17.
Azhar Mahmood Itrat Fatima Shaheen Kosar Rehana Ahmed Abdul Malik 《Magnetic resonance in chemistry : MRC》2010,48(2):151-154
Prunusins A (1) and B (2), the new C‐alkylated flavonoids, have been isolated from the seed kernels of Prunus domestica. Their structures were assigned from 1H and 13C nuclear magnetic resonating spectra, DEPT and by correlation spectroscopy, HMQC and HMBC experiments. 3, 5, 7, 4′‐Tetrahydroxyflavone (3) and 3, 5, 7‐trihydroxy‐8, 4′‐dimethoxyflavone (4) have also been reported from this species. Both compounds (1) and (2) showed significant antifungal activity against pathogenic fungus Trichophyton simmi. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
18.
A new pentacyclic triterpenoid, 2alpha,3beta-dihydroxylup-12-en-28-oic acid (1) and a rarely encountered pentacyclic triterpenoid, 3beta-hydroxylup-12-en-28-oic acid (2), together with five known compounds, friedelin (3), 3beta-friedelinol (4), betulinic acid (5), oleanolic acid (6) and beta-sitosterol (7) were isolated from the chloroform extract of stem bark of Eugenia grandis (Syn: Syzygium grande). The structure and stereochemistry of the new compound (1) and the rarely encountered compound (2) were established by 1D and 2D NMR spectroscopic techniques. All the above isolated compounds from this plant are reported for the first time. 相似文献
19.
Antje Bodensieck Olaf Kunert Ernst Haslinger Rudolf Bauer 《Helvetica chimica acta》2007,90(1):183-195
A total of 21 natural products, 1 – 21 , were isolated from a supercritical CO2 extract of the rhizomes of Petasites hybridus. Thereby, seven new eremophilane (= (1S,4aR,7R,8aR)‐decahydro‐1,8a‐dimethyl‐7‐(1‐methylethyl)naphthalene) sesquiterpenes, compounds 4, 5, 9, 11, 12, 15 , and 17 , were identified. The new constituent 9‐hydroxyisobakkenolide ( 15 ) is the first representative of a group of compounds closely related to the well‐known, but rare, bakkenolides. Tsoongianolide B ( 18 ) and its degradation product ligularenolide ( 19 ) were found as new Petasites constituents as well. The known eremophilanolide 2 was isolated from a plant source for the first time and the oxofuranopetasin 16 was isolated for the first time from the rhizomes of P. hybridus, together with eight other known compounds. The C(8)‐epimeric 2‐[(tigloyl)oxy]eremophilanolides 3 and 8 could clearly be differentiated. All structures were established by extensive 1D‐ and 2D‐NMR experiments (Tables 1–3), and confirmed by in‐depth GC/MS and HPLC/MS experiments. 相似文献
20.
Xiongming Luo Shuhua Qi Hao Yin Zhihui Xiao Si Zhang 《Magnetic resonance in chemistry : MRC》2009,47(12):1110-1114
Four new coumarins, micromelosides A–D, together with four known coumarins were isolated from the stem bark of Micromelum falcatum. The complete assignments of the 1H and 13C NMR chemical shifts for these new compounds were achieved by means of 1D and 2D NMR techniques, including 1H‐1H COSY, HSQC, HMBC and NOE difference. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献