PubMed Health⌕ Search

Biomedical subjects

Lisheng Ding

Publications and source records attributed to Lisheng Ding.

9 recordsLinked to original sources
PubMed2007

Analysis of sodium adduct paeoniflorin, albiflorin and their derivatives by (+)ESI-MSn, DFT calculations and computer-aided mass spectrometry analysis program.

In order to analyze paeoniflorin, albiflorin and their derivatives (PADs) in Paeonia Lactiflora rapidly and effectively, (+)ESI-MS(n) experiments were conducted, from which two diagnostic fragment patterns were acquired. Meanwhile, the dehydration ability of aglycones of PADs was obtained by calculating their activation energy using density functional theory, through which the unique dehydration phenomenon of benzoylalbiflorin, compared with benzoylpaeoniflorin, was interpreted. In addition, a computer-aided mass spectrometry analysis program was developed to facilitate the analysis of the unknown compound by suggesting the possible structure of the analyte.

Algorithms↗
PubMed2006

Skeleton-rearranged pentacyclic diterpenoids possessing a cyclobutane ring from Euphorbia wallichii.

[structure: see text] Two novel rearranged trachylobane diterpenoids, designated as wallichanol A (2) and wallichanol B (3), consisting of an unprecedented pentacyclic skeleton named wallichane with a cyclobutane ring, and a new ent-trachylobane diterpenoid, 3-oxo-ent-trachyloban-17-oic acid (1), were isolated from the roots of Euphorbia wallichii. Their structures were elucidated by comprehensive analysis of 2D-NMR spectroscopic data, with the stereochemistry of 1 confirmed by X-ray crystallographic study. All of these compounds potently block osteoclastogenesis in vitro, suggesting a potential therapeutic application in prevention of osteoporosis.

Bone Resorption↗
PubMed2006

ESI-QqTOF-MS/MS and APCI-IT-MS/MS analysis of steroid saponins from the rhizomes of Dioscorea panthaica.

Using high-resolution quadrupole time-of-flight mass spectrometry along with an electrospray ionization source (ESI-QqTOF-MS), accurate molecular weights of 13 steroid saponins extracted from the rhizomes of Dioscorea panthaica were acquired and the corresponding molecular formulae obtained. In order to elucidate the fragmentation pathways of steroid saponins in D. panthaica, 10 authentic samples were investigated using ESI-QqTOF-MS/MS. In addition, atmospheric pressure chemical ionization mass spectrometry combined with ion trap tandem mass spectrometry (APCI-IT-MS/MS) was used to analyze the structures of 13 steroid saponins in D. panthaica. Through the analysis of their tandem mass data, diagnostic fragment ions of the spirostanol and furostanol steroid saponins in D. panthaica were detected as m/z 271.2056 and 253.1951. In addition, four pairs of isomers were detected and the possible structures of four unknown steroid saponins in D. panthaica speculated. ESI-TOF and APCI-MS(n) have proved to be effective tools for research on fragmentation mechanism of steroid saponins and the rapid determination of native steroid saponins in extract mixture, thereby avoiding tedious derivation and separation steps.

Carbohydrate Sequence↗
PubMed2006

Differentiation of three pairs of aconite alkaloid isomers from Aconitum nagarum var. lasiandrum by electrospray ionization tandem mass spectrometry.

Three pairs of isomers of aconite alkaloids from Aconitum nagarum var. lasiandrum have been investigated by electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (MS/MS) employing ion-trap and quadrupole time-of-flight mass spectrometers in positive mode. Based on the differences of their fragmentation pathways and special fragment ions, three pairs of isomers of aconite alkaloids were differentiated. In addition, fragmentation laws of some veatchines and the discrepancy of fragmentation mechanisms between veatchine-type and aconitine-type alkaloid were also concluded. In the case of veatchines, a radical would be formed by homolysis of C18--C4 or C18--H bonds, followed by elimination of a series of C(2)H(2) and C(2)H(4). Moreover, the retro-Diels-Alder (RDA) reaction occurred in the E-ring and double-electron transfer triggered by the positive charge on C1 led to the formation of diagnostic ions at m/z 216. With regard to aconitine-type alkaloids, the N-substituent is not eliminated easily. Although there is no carbonyl group on some aconitine-type alkaloids, with hydroxyl and methoxyl on C15 and C16 respectively, CO was readily eliminated through tautomerization.

Aconitum↗
PubMed2006

A new amide from Thyrocarpus glochidiatus.

A new amide, 4-hydroxy-N-[4-[3-(4-hydroxy-phenyl)-E-acryloylamino]-butyl]-benzamide, trivially named as glochidiatusamide (1), along with 5 known compounds, beta-sitosterol, daucosterol, coffee acid, ethyl caffeate, and kaempferol-3-O-beta-D-glucoside, were isolated from the ethanol extract of Thyrocarpus glochidiatus Maxim. Their structures were elucidated by the spectral and chemical evidence.

Benzamides↗
PubMed2002

Chemical constituents of the aerial parts of Schnabelia tetradonta.

A phytochemical study on the ethanol extract of the aerial parts of Schnabelia tetradonta led to the isolation of five new compounds, 1-5, together with seven known compounds. The structures of the new compounds were elucidated on the basis of spectral data interpretation as 2alpha,3alpha,23,29-tetrahydroxyolean-12-en-28-oic acid (1), 3-O-beta-d-glucuronopyranosyl-2beta,3beta,16beta-trihydroxy-28-norolean-12-en-15-on-23-oic acid (2), 21-O-beta-d-glucopyranosyl-3beta,21alpha,30-trihydroxyolean-13(18)-en-24-oic acid (3), 6-C-beta-l-arabinopyranosyl-8-C-alpha-l-arabinopyranosylapigenin (4), and 4-acetylaminoethylphenyl 1-O-[6-O-(Z)-p-methoxycinnamoyl-beta-d-glucopyranosyl(1-->2)]-[beta-d-glucopyranosyl(1-->3)]-alpha-l-rhamnopyranoside (5), respectively.

China↗