نتایج جستجو برای: 1h nmr

تعداد نتایج: 79250  

Journal: :Phytochemistry 2001
I Muhammad D C Dunbar R A Khan M Ganzera I A Khan

The C-8-(S) isomer of deoxyloganic acid (7-deoxyloganic acid), together with beta-sitosteryl glucoside, five known stereoisomeric pentacyclic oxindole alkaloids and the tetracyclic oxindole isorhyncophylline, were isolated from the inner bark of Uncaria tomentosa. Structures of the isolated compounds were based on 1H and 13C NMR data, mainly 2D NMR experiments, including 1H-13C HMBC and 1H-1H N...

2013
Maria Eugenia Castro Maria Judith Percino Victor M. Chapela Margarita Ceron Guillermo Soriano-Moro Jorge Lopez-Cruz Francisco J. Melendez

A combined theoretical and experimental study on the structure, infrared, UV-Vis and 1H NMR data of trans-2-(m-cyanostyryl)pyridine, trans-2-[3-methyl-(m-cyanostyryl)]pyridine and trans-4-(m-cyanostyryl)pyridine is presented. The synthesis was carried out with an efficient Knoevenagel condensation using green chemistry conditions. Theoretical geometry optimizations and their IR spectra were ca...

2017
Pingping Zou Yuelin Song Wei Lei Jun Li Pengfei Tu Yong Jiang

Cistanche deserticola (CD) is one of the two authoritative source plants of Cistanches Herba, a well-known medicinal plant. Herein, 1H NMR spectroscopy was employed to characterize the chemical profile and to distinguish the different parts, as well as to propose a new processing workflow for CD. Signal assignment was achieved by multiple one and two dimensional NMR spectroscopic techniques in ...

Journal: :iranian journal of pharmaceutical research 0
m iranshahi m ghiadi a sahebkar a rahimi c bassarello s piacente

phytochemical investigation of the dichloromethane extract of the dried roots of ferula badrakema resulted in the identification of one new and six known compounds. known compounds were sesquiterpene coumarins: mogoltacin, feselol, badrakemin acetate, ferocaulidin, conferone and conferol acetate. the new compound was a sesquiterpene, named badrakemonin. the structures of these compounds were el...

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 1994
mehran chiaci ali mohajeri

conformational properties of n-aryl-1-azacyclooctan-5- ones with a p-methyl, m-methyl, and p-methoxy group as a substituent have been studied by 1h-nmr, 13c-nmr and ir spectroscopies. transannular interaction of the two functional groups have been examined from the ring inversion barriers and the carbonyl vibrational frequencies with reference to the corresponding data of the respective monofun...

Journal: :Molecules 2011
Ting Lin Guang Hui Wang Xiang Lin Zhi Yu Hu Quan Cheng Chen Yang Xu Xiao Kun Zhang Hai Feng Chen

Four new metabolites, including three new oblongolides named C1, P1, and X1 (1-3) and 6-hydroxyphomodiol (10), along with eight known compounds--oblongolides B (4), C (5), D (6), O (7), P (8) and U (9), (3R,4aR,5S,6R)-6-hydroxy-5-methylramulosin (11), and (3R)-5-methylmellein (12)--were isolated from the endophytic fungal strain Phomopsis sp. XZ-01 of Camptotheca acuminate. Their structures wer...

Journal: :The Journal of antibiotics 1991
T Sonoda H Osada J Uzawa K Isono

A new glutarimide antibiotic named actiketal was isolated from the culture fluid of the epiderstatin-producing streptomycete, Streptomyces pulveraceus subsp. epiderstagenes. The IC50 of the antibiotic for inhibition of the incorporation of [3H]thymidine into epidermal growth factor-stimulated Balb/MK cells was 14.5 microM. The structure of this compound was determined by 1H and 13C NMR spectros...

Mahmoud Osanloo Reza Ghiasi,

In this investigation, the structural, electronic properties, 13C and 1H NMR parameters and firsthyperpolarizability of Z-Ligustilide were explored. As well, the solvent effect on structural parameters, frontier orbital energies, electronic transitions, and 13C and 1H NMR parameters was illustrated based on Polarizable Continuum Model (PCM).These consequences specify that the polarity of solven...

1-substituted 1H-tetrazoles were efficiently synthesized under solvent-free conditions from the reaction of primary amines, triethylorthoformate, and sodium azide in the presence of Cu/C as a heterogeneous catalyst. Various amines including aromatic and heteroaromatic amines were used to afford the corresponding products in good to excellent yields. The characterization of corresponding product...

2012
Pui Hei Chan Ken YZ Zheng Karl WK Tsim Henry Lam

UNLABELLED BACKGROUND With the gaining popularity of commercially prepared decoctions of herbal medicines on the market, an objective and efficient way to reveal the authenticity of such products is urgently needed. Previous attempts to use chromatographic or spectroscopic methods to identify ginseng samples made use of components derived from methanol extracts of the herb. It was not establ...

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