From the aerial parts ofNauclea officinalis (Pierre ex Pitard) Merr. et Churl, one new indole alkaloid paratunamide E (1) has been isolated together with six known indole alkaloids, paratunamide A (2), nauclealotide C (3), nauclealotide A (4), vincosamide (5), strictosamide (6) and naucleamide F (7). Naucleamide F (7) was isolated from Nauclea officinalis for the first time. All of the seven compounds above were elucidated by spectroscopic methods including 1 D and 2 D NMR soectroscoDic analyses.
The aim of current study was to investigate the chemical components of the aerial part of Reineckia carnea,collected in Yunnan Province of China.Repeated column chromatography(CC)separations were performed to isolate and purify components. Compounds were identified by the analysis of their 1D and 2D NMR data as well as IR and MS spectra.A new pregnane-type glycoside,named 1α,3β-diol-5β-pregn-16-ene-20-one-1-O-α-L-arabinosyl-(1→2)-α-L-rhamnoside(1),together withβ-amyrin(2), stigmasterol(3),α-spinasterol-3-O-β-D-glucoside(4),naringenin(5),β-sitosterol(6)and daucosterol(7),were isolated from ethyl acetate(EtOAc)and normal butanol(n-BuOH)extracts.Compounds 2,4,5 were isolated from this plant for the first time.
A new triterpenoid saponin (compound 1), together with a known one (compound 2) was isolated from the roots of Silene rubicunda Franch. The isolation and purification were performed by a series of chromatographic techniques including silica gel, sephadex LH-20, and reversed-phase HPLC. Their structures were elucidated on the basis of combination of mass spectrometry and 1D, 2D NMR spectroscopy, and the new compound was identified as 3-O-{β-D-galactopyranosyl-(1→2)-[β-D-xylopyranosyl- ( 1→3 )]-β-D-glucuronopyrannosyl } -28-O- { β-D-xylopyranosyl-( 1 →3 )-β-D-xylopyranosyl-( 1 α4)-α-L-rhamnopyranosyl-(1→2)- [β-D-quinovopyranosyl-(1α4)]-β-D-fucopyranosyl} quillaic acid.
In the present study, in order to investigate the chemical constituents of Physal& alkekengi L. var. franchetii (Mast.) Makino, the isolation of ingredients was performed by repeated chromatography on silica gel, Sephadex LH-20 and preparative HPLC. Their structures were identified based on 1D, 2D NMR, and mass spectral analysis, A total of 14 compounds were obtained, and their structures were identified as physalin P (1), 4,7-didehydroneophysalin B (2), physalin D (3), 5α-hydroxy-25,27-dihydro-7- dehydro-7-deoxyneophysalin A (4), 4,7-didehydrophysalin B (5), ursolic acid (6), wogonin (7), blumenol A (8), nobiletin (9), liquiritigenin (10), schizandrin (11), 5-hydroxymethylfurfural (12), 5-(hydroxymethy1)-2-(dimethoxymethyl)furan (13), 1-O- [3-O-2-methyl-5-(2,3,4-trimethyl)pheny1-2,3-pentanedi]-β-D-xylopyranosyl-(1→6)-β-D-galactopyranoside (14). Among them, compound 14 is a new compound. Compounds 7-11, 13 are isolated from Physalis alkekengi L. var.franchetii (Mast.) Makino for the first time.
A simple, rapid and sensitive LC-MS/MS method was developed to quantify erlotinib and its active metabolite, OSI-420, simultaneously in BALB/c nude mice plasma. Erlotinib, OSI-420 and propranolol (internal standard) were extracted from nude mice plasma samples by liquid-liquid extraction. Separation was achieved on a reversed phase ClS column with a mobile phase of acetonitrile-water (35:65, v/v) containing 5 mM ammonium formate (pH = 3.0). All compounds were monitored by mass spectrometry with electrospray positive ionization. The lower limit of quantification was 0.5 ng/mL for both erlotinib and OSI-420; accuracy was estimated by relative error, which was in the range from 0.07% to 8.00% for erlotinib and -2.83% to 6.67% for OSI-420; precision was validated by relative standard deviation, which was from 2.28% to 15.12% for erlotinib and from 1.96% to 11.50% for OSI-420. This method was applied to a pharmacokinetic study of BALB/c nude mice following oral administration of erlotinib at 12.5 mg/kg. A 2-compartment model was used to fit the pharmacokinetics of erlotinib and 1-compartment model for the pharmacokinetics of OSI-420. The ratio of the active metabolite to parent drug in mice was greater than previously reported in humans and probably reflects interspecies difference in the rate of conversion of erlotinib to OSI-420.