MS spectra comparison

One new sesquiterpene, (4S,7R,10S)-2-oxo-4,10,11-trihydroxyguaia-1(5)-ene, and five lignans, kadsuralignan J, isovaleroylbinankadsurin A, schizandrin O, futokakadsurin C and arisantetralone were isolated from the roots of Kadsura induta. Their chemical structures were revealed by MS, 1D and 2D NMR spectra in comparison with the reported data. The absolute configuration of compound 1 was determined by calculation of its theoretical ECD spectra and compared with the experimental results.

9p dianmotminh02 03-05-2024 4 2   Download

Miliusa velutina Dun Hook. f. et. Thoms is the rare and native plant, belongs to the Annonaceae family. The isolated compounds in Miliusa genus showed that many function groups and have diverse bioactivities. From the ethyl acetate extract of the trunk of Miliusa velutina, three compounds were isolated and determined based on 1D, 2D NMR spectra, MS and combined comparison with references.

5p viberkshire 09-08-2023 6 4   Download

Nontargeted analysis based on mass spectrometry is a rising practice in environmental monitoring for identifying contaminants of emerging concern. Nontargeted analysis performed using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC/TOF-MS) generates large numbers of possible analytes.

8p viginny 23-12-2022 6 2   Download

One lignan (7′S,8′R,8S)-4,4′-dihydroxy-3,3′,5,5′-tetramethoxy-7′,9-epoxylignan-9′-ol-7-one (1) together with four neolignans (7α,8α)-dihydrodehydrodiconiferyl alcohol 9-O-β-D-glucopyranoside (2), (7α,8α)-dihydrodehydrodiconiferyl alcohol 9′-O-β-D-glucopyranoside (3), icariside E3 (4), and icariside E5 (5) were isolated from Pouzolzia sanguinea. Their chemical structures were elucidated by ESI-MS, NMR spectra, as well as in comparison with the data reported in literature.

7p cothumenhmong11 06-05-2021 10 2   Download

Three dihydrostilbene glycosides, 3,5-dihydroxydihydrostilbene 4′-O-β-D-glucopyranoside (1), 3,5- dimethoxydihydrostilbene 4′-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside (2), 5,4′-dihydroxydihydrostilbene 3-O-β-D-glucopyranoside (3), and one lignan, nudiposide (4) were isolated from the methanol extract of leaves of Camellia sasanqua Thunb. Their chemical structures were determined by using ESI-MS and NMR spectra as well as in comparison with the reported data. Compounds 3 and 4 were reported from Camellia genus for the first time.

5p cothumenhmong11 06-05-2021 15 2   Download

Their chemical structures were determined using ESI-MS, 1D NMR, and 2D NMR spectra as well as by comparison of the spectral data with those reported in the literature. Compounds 4 and 5 were reported from Xanthium genus for the first time. To our best knowledge, all these compounds were firstly reported from X. strumarium growing in Vietnam.

6p cothumenhmong11 06-05-2021 18 2   Download

Mass spectrometry (MS) is producing high volumes of data supporting oncological sciences, especially for translational research. Most of related elaborations can be carried out by combining existing tools at different levels, but little is currently available for the automation of the fundamental steps.

10p vioklahoma2711 19-11-2020 7 2   Download

Peptide identification based upon mass spectrometry (MS) is generally achieved by comparison of the experimental mass spectra with the theoretically digested peptides derived from a reference protein database.

6p vioklahoma2711 19-11-2020 12 1   Download

The classification of samples on a molecular level has manifold applications, from patient classification regarding cancer treatment to phylogenetics for identifying evolutionary relationships between species.

12p vioklahoma2711 19-11-2020 7 1   Download

Maesa membranacea A. DC. (Myrsinaceae) has been traditionally used for the treatment of fever and hepatitis. The phytochemical investigation of Maesa membranacea stems has led to the isolation of six compounds including kaempferol (1), (-)-epicatechin (2), betulinic acid (3), p-hydroxybenzoic acid (4), vanilic acid (5), and protocatechuic acid (6). The chemical structures of these compounds have been determined by nuclear magnetic resonance (NMR), mass spectrometry (MS) data, and by comparison with previously reported works.

4p chauchaungayxua8 02-10-2020 21 1   Download

Using various chromatography methods, two known cycloartanes, 24-methylenecycloartane-3β,6β,7β,16β-tetraol (1) and riparsaponin (2), together with two known flavonol glycosides, quercetin 3-O-β-D-glucopyranoside (3) and quercetin 3-O-α-L-rhamnopyranosyl (1→6) β-D-glucopyranoside (4) were isolated from the methanol extract of the leaves of Homonoia riparia Lour. Their structures were determined by MS and 1D-, 2D-NMR spectra, as well as by comparison with those reported in the literature.

5p bautroibinhyen211 26-11-2018 15 1   Download

From the leaves of Fissistigma acuminatissima growing in Vietnam, two flavonoids, catechin and isorhamnetin-3-o-rutinoside were isolated. Their structures were characterized on the basis of MS and NMR spectra data and comparison with reported data.

4p chikychiky 11-11-2018 17 1   Download

Using various chromatography methods, four sesquiterpene phenols, dictyoceratin C (1), polyfibrospongol A (2), polyfibrospongol B (3), and 19-hydroxy-polyfibrospongol B (4) were isolated from the methanol extract of the Vietnamese marine sponge Smenospongia cerebriformis. Their structures were determined by 1D-, 2D-NMR spectra, HR-ESI-MS and in comparison with those reported in the literature.

5p giesumanh 10-11-2018 15 1   Download

Using various chromatography methods, three merosesquiterpenes belonging to sesquiterpene quinone type, neodactyloquinone (1), dactyloquinone D (2), and dactyloquinone C (3) together with two indole derivatives indole-3- aldehyde (4) and indole-3-cacboxylic methyl ester (5) were isolated from the methanol extract of the Vietnamese marine sponge Smenospongia cerebriformis. Their structures were determined by 1D-, 2D-NMR spectra, HR-ESI-MS and in comparison with those reported in the literature.

5p giesumanh 10-11-2018 14 0   Download