MS and NMR spectroscopic data

Three flavones (1-3) were isolated from the aerial part of Tithonia diversifolia (Hemsl.) A. Gray growing in Hoa Binh province, Vietnam. Their structures were identified as hispidulin (1), nepetin (2) and luteotin (3) by analysis of these spectroscopic MS, NMR data and comparison with reported data.

4p viericschmid 12-01-2022 16 0   Download

The newly synthesized compounds were characterized and confirmed by analytical and spectroscopic data (IR, MS, 1H NMR, and 13C NMR). Pyrazolo[1,5-a]pyrimidines 5a–c and 9a–c and Schiff bases 11b–f were investigated for their cytotoxicity against four human cancer cell lines (colon HCT116, lung A549, breast MCF-7, and liver HepG2) according to SRB assay and the structure–activity relationship was discussed.

12p langthannam 29-12-2021 14 0   Download

This is the first time that it is from its roots, which were collected at Vi Xuyen district - Ha Giang province, were five compounds isolated. These compounds include two phenylethanoid glycosides, verbascoside (1), arenarioside (2); one iridoid glucoside, myxopyroside (3); one indole, 3-formylindole (4), and one furfural, 5-hydroxymethyl furfural (5). Their chemical structures were determined by ESI-MS, 1D-, 2D-NMR spectroscopic data analysis as well as in comparison with those reported in the literatures.

9p spiritedaway36 25-11-2021 4 1   Download

Seven compounds were isolated and characterized from the culture broth of the marine bacteria Nocardiopsis sp. (strain G057), which was isolated from sediment collecting at Cô Tô – Quảng Ninh. Their structures were determined by spectroscopic analysis including MS and 2D NMR, as well as by comparison with reported data in the literature. All compounds were evaluated for their antimicrobial activity against a panel of clinically significant microorganisms. Compounds 1, 2 and 7 selectively inhibited Escherichia coli with a MIC value of 32, 64, 8 μg/mL, respectively.

5p cothumenhmong11 10-05-2021 8 1   Download

Eight sesquiterpenoids including costunolide (1), parthenolide (2), 11α,13-dihydroparthenolide (3), 9β-hydroxydihydroparthenolide (4), (-)-bisparthenolidine (5), 11α,13-dihydro-β-cyclocostunolide (6), α-cadinol (7), magnograndiolide (8) were isolated from the barks and roots of Michelia alba. The structures of these compounds were elucidated by spectroscopic methods (MS, 1D and 2D NMR) and comparison with the reported data. Compounds 5-8 have been isolated for the first time from Michelia alba.

7p nguaconbaynhay11 16-04-2021 14 2   Download

This paper describes the isolation and structure elucidation of seven compounds isolated from this lichen. Phytochemical investigations of the ethyl acetate extract of the lichen P.tinctorum led to the isolation of seven pure compounds. Their chemical structures were elucidated by extensive HR-ESI-MS and NMR spectroscopic analysis and comparison with previously published data.

5p kequaidan10 05-03-2021 14 2   Download

Friedelin (1), 5α-stigmast-22-ene-3-one (2), chrysophanol (3), physcion (4), 4'-O-methylalpinumisoflavone (5), and tetracosanoic acid (6) were isolated from the n-hexane extract of Leonotis nepetifolia (L.) R. Br collected at Ba Ria - Vung Tau province, Vietnam. The chemical structures of these compounds were elucidated by MS and NMR spectroscopic analysis as well as compared with data in the literature. These compounds were known in Leonotis nepetifolia for the first time. Further studies on this plant are in progress.

4p nguaconbaynhay10 20-02-2021 10 3   Download

The maceration was applied to the seeds of the plant to afford the crude extract which was then fractionated by liquid-liquid extraction to obtain the ethyl acetate extract. The extract was carried out by using normal phase silica gel column chromatography and thin-layer chromatography. Analysis of spectroscopic data including HR-ESI-MS, 1D and 2D-NMR and a comparison of the NMR data with that in the literature led to the structural elucidation of isolated compounds.

4p larachdumlanat127 02-01-2021 8 1   Download

Four lignans, (+)-aptosimon (1), (+)-isolariciresinol (2), (-)-cleomiscosin A (3), and (-)-cleomiscosin C (4) were isolated from the leaves of Amesiodendron chinense (Mer.) Hu. Their chemical structures were determined by spectroscopic analysis including MS, 1D and 2D NMR as well as by comparison with reported literatures. All compounds were evaluated for cytotoxic activity against five human cancer cell lines, KB, SK-LU-1, MCF-7, HepG-2, and SW-480. The compounds showed weak cytotoxic activity with IC50 values ranging from 32.61 to 95.18 µg/mL.

8p nguyenxuankha_bevandan 14-08-2020 12 1   Download

Three dolabrane-type diterpenoids (1–3) and a lignan were isolated from a methanolic extract of C. decandra (Griff.) W. Theob. stem barks using various chromatographic separations. Their structures were elucidated to be tagalsine X, tagalsin P, ent-5α,2- oxodolabr-3-ene-3,15,16-triol, and pinoresinol by detailed analysis via spectroscopic techniques (1D, 2D NMR, and ESI-MS data) as well as comparison with those reported.

7p nguyenxuankha_bevandan 14-08-2020 18 1   Download

Study indicated that F. lini was able to catalyze dehydrogenation reactions selectively. Structures of compounds 1–14 were determined through NMR, HRFAB-MS, and IR spectroscopic data. Compounds 1–14 were identified as non-cytotoxic against BJ human fibroblast cell line (ATCC CRL-2522). Metabolite 5 (81.0 ± 2.5%) showed a potent activity against TNF-a production, as compared to the substrate 1 (62.5 ± 4.4%). Metabolites 2 (73.4 ± 0.6%), 8 (69.7 ± 1.4%), 10 (73.2 ± 0.3%), 11 (60.1 ± 3.3%), and 12 (71.0 ± 7.2%), also showed a good inhibition of TNF-a production. Compounds 3 (IC50 = 4.4 ± 0.

10p partimesinhvien 08-05-2020 12 1   Download

Five prenylated caged xanthones: desoxymorellin (1), morellic acid (2), gambogic acid (3), isogambogic acid (4) and 10α-butoxy gambogic acid (5), were isolated from the stem bark of Garcinia hanburyi collected in Vietnam. Their structures were elucidated by detailed 1D, 2D NMR, MS spectroscopic analyses and compared with reported data. Two major constituents, gambogic acid and isogambogic acid, displayed strong cytotoxicity against LLC and SK-LU-1cell lines with IC50 values in the range from 0.35±0.05 µM to 2.26±0.19 µM.

10p nguyenminhlong19 22-04-2020 29 1   Download

In this study, phytochemical investigation of the n-hexane and ethyl acetate extract of leaves and twigs of Urena lobata L. led to the isolation of β-sitosterol (1), β-sitosterol3-O-β-D-glucopyranoside (2), 2-acetylamino-3-phenylpropyl 2-benzoylamino-3-phenylpropanoate (3), quercetin (4), and trans-tiliroside (5). Their chemical structures were determined by spectroscopic methods, including MS, 1D-, 2D- NMR, and by comparing their spectral data with those reported in previous papers. Compounds 3 and 5 were isolated for the first time from Urena lobata L.

8p abcxyz123_02 03-03-2020 14 2   Download

Phytochemical research on the chloroform and ethyl acetate extracts of the rhizomes of Curculigoannamitica Gagnep. collected in Binh Chau - Phuoc Buu Nature Reserve, Ba Ria - Vung Tau province, led to the isolation of five phenolic compounds namely 3,4- dimethoxysalicylicacid(1), 2-hydroxy-6-methoxybenzoicacid(2), 4-hydroxybenzoic acid (3), pcoumaric acid (4) and 2-(ethoxymethyl) benzene-1,4-diol (5). Their chemical structures were confirmed by spectroscopic methods including HR-ESI-MS, ESI-MS,1D and 2D-NMR and compared with reported data.

7p abcxyz123_02 03-03-2020 17 1   Download

Three natural compounds including betulin (1), betulinic acid (2) and lupeolactone (3) were isolated from the dichloromethane extract of Helicteres hirsuta Lour. for the first time. Their structures have been elucidated by modern spectroscopic methods as IR, 1H-NMR, 13C-NMR, DEPT, HSQC, HMBC, MS and by comparison with those of previously reported data.

8p slimzslimz 08-12-2019 37 0   Download

Today, most investigations of the plant metabolome tend to be based on either nuclear magnetic resonance (NMR) spectroscopy or mass spectrometry (MS), with or without hyphenation with chromatography. Although less sensitive than MS, NMR provides a powerful complementary technique for the identification and quantification of metabolites in plant extracts.

13p trinhthamhodang1 16-11-2019 15 0   Download

From the alcoholic extract of the aerial parts of Orthosiphon stamineus Benth., three flavonols have been isolated. Their chemical structures were elucidated to be 5,7,3’,4’-tetramethylquercetin (1), 3’-hydroxy-3,5,7,4’- tetramethoxyflavone (2), and 3,5-dihydroxy-7,3',4'-trimethoxyflavone (3), by combining spectroscopic data and physicochemical data analyses (including IR, UV, NMR and MS).

5p bautroibinhyen211 26-11-2018 23 0   Download

Seven terpenoids were isolated from the dried leaves of Pinus dalatensis Ferré, including one caryolane sesquiterpenoid (1), five labdane diterpenoids (2, 3, 4, 5, 6) and one serratane triterpenoid (7). The structures of the isolated compounds were determined on the basic of spectroscopic methods (ESI-MS, NMR) and comparison with reported data. Among these compounds, the mixture of compounds 2 and 3 showed inhibitory effects on the growth of acute myeloid leukemia (OCI-AML) cells. This is the first report on the chemical compositions of Pinus dalatensis in Vietnam.

5p bautroibinhyen211 26-11-2018 33 1   Download

Chemical investigation of the leaves of Celastrus hindsii growing in Quang Binh, Vietnam led to the isolation and structural elucidation of three triterpenes, 3-friedelanol, 3-friedelanone and canophyllol. These structures were determined on the basis of MS and NMR spectroscopic data.

4p chikychiky 11-11-2018 36 1   Download

Five compounds L-phenyl alanine (1), 1-methyl-6-acetyl-α-D-glucopyranoside (2), thymine (3), uracil (4), and (2R,3S)-butane-2,3-diol (5) were isolated and characterized from the culture broth of the marine bacterium Micromospora sp. (G047 strain), which was isolated from the sediment collecting from the coast of Co To – Quang Ninh. The structures of all isolates were determined by spectroscopic analysis including MS and 2D NMR, as well as by comparison with reported data in the literature.

4p giesumanh 10-11-2018 31 1   Download