ABSTRACT
The chemical constituents of Viburnum taitoense Hayata were investigated using column chromatography silica gel and Sephadex LH-20, etc. Seven pentacyclic triterpenoids were isolated and their structures were elucidated by spectral data and physicochemical properties as 3β,6β-dihydroxy olean-11,13(18)-dien-28-acid (1), 3β-hydroxy olean-11,13(18)-diene-28-acid (2), 12-ene-olean-28-acid-3β-palmitate (3), 3β-acetylcocodiol (4), corosolic acid (5), uvaol (6) and ursolic acid (7). Among them, compound 1 is a new oleanane type triterpenoid and its absolute configuration was confirmed by single-crystal X-ray diffraction data. Compounds 2-5 were isolated from this genus for the first time. All the compounds were evaluated for their anti-inflammatory activities in vitro, and compound 5 showed significant inhibitory activity against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells with an IC50 of 25.52 ± 0.56 μmol·L-1 when compared to the positive control, quercetin (IC50 of 25.46 ± 0.62 μmol·L-1).
ABSTRACT
Two new flavonoid glycosides were isolated from the aerial parts of Nervilia fordii by various chromatographies such as D101 macroporous resin, ODS and preparative HPLC chromatographic techniques. Their structures were elucidated as rhamnocitrin-3-O-β-glucopyranosyl-4'-O-β-galactosyl-(1→3)-glucopyranoside (1) and 7, 3'-di-O-methylquercetin-4'-O-[β-galactosyl-(1→3)-β-glucopyranosyl]-3-O-β-glucopyranoside (2) on the basis of extensive spectroscopic analyses, including 1D-, 2D-NMR, HR-ESI-MS and analytical hydrolysis.
ABSTRACT
To study the chemical constituents of Nervilia fordii (Hance) Schltr., various chromatographic methods were used, including D101 macroporous resin, silica gel, ODS and preparative HPLC chromatographic techniques. A new labdane diterpenoid glycoside named as nervilifordoside A was isolated from 60% EtOH extract of Nerviliafordii. The structure of compound 1 was elucidated as 12, 17-epoxy-3-hydroxy-17-methoxy-labdan-13-en-16, 15-olide 3-O-alpha-rhamnopyranosyl-(1 --> 2)-O-beta-glucopyranoside on the basis of HR-MS, 1D and 2D NMR spectroscopic data as well as chemical methods.
Subject(s)
Chromatography, High Pressure Liquid , Molecular Structure , Orchidaceae , Chemistry , Plants, Medicinal , ChemistryABSTRACT
Objective To synthesize and analyze sodium 18F-fluoroacetate (FAC) and its precursor ethyl O-mesylglycolate (EOMG). Methods EOMG was synthesized using modified method. Its chemical purity was checked by HPLC and its structure was elucidated on the basis of spectral analyses. Final product of 18F-FAC was synthesized based on general nucleophilic reactions module Explora GN using EOMG as a precursor. Liquid chromatography Explora LC was applied to get rid of its chemical impurities.Then HPLC and radio-thin layer chromatography were used to assay its radiochemical purity, chemical purity and specific activity. Results EOMG was synthesized and identified. Its yield was 70% and its chemical purity was 97.0% (calculated by chromatographic peak area). The radiochemical purity of 18F-FAC was more than 98%, and its specific activity was 236. 5 MBq/μmol. Conclusion This synthetic method for 18F-FAC and its precursor can be defined as effective and highly quality-controlled.