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A simple, E-stereoselective route for the synthesis of the biologically active Com-pounds trans-pterostilbene and tetrumethoxy stilbene from the readily available starting materials 3,5-dimethoxy benzyl alcohol and 4-hydroxy benzaldehyde was developed using Julia olefination as a key reaction. [ABSTRACT FROM AUTHOR]

A new, simple, precise, and rapid high performance thin layer chromatography (HPTLC) method has been developed and validated for the simultaneous quantitative determination of three phenolic acids, namely, 3,5-O-dicaffeoylquinic acid, 3,4-O-dicaffeoylquinic acid and chlorogenic acid from flower buds of Lonicera japonica. The separation of these compounds was carried out on silica gel 60F254 eluted with ethyl acetate:chloroform:methanol:formic acid:water (6:2.5:1.5:0.6:0.1 v/v/v/v) and a detection wavelength at 330 nm. The developed method gave a good linear regression relationship between peak area and an observed concentration range of 200-1200 ng spot-1 for the three aforementioned marker compounds. Spike recoveries were within 97.81-101.59% and the RSD values of precision were in the range of 0.65-3.21%. The method presented good results for the following parameters: selectivity, linearity, accuracy, precision, robustness, as well as limit of detection and limit of quantification. Therefore, this method could provide a simple analytical tool for the quality control of Lonicera japonica raw material and its products. [ABSTRACT FROM AUTHOR]

Simple isolation of (±)‐schizandrin ( 1 ) and preparation of its analogues ( 6 – 8 ) via acylation of (±)‐schizandrin ( 1 ) are described. The key strategy in the synthesis involves the catalytic acylation reaction of 1 with several acylating reagents. [ABSTRACT FROM AUTHOR]

Four isomeric bioactive saponin compounds named escin la, isoescin la, escin Ib, and isoescin Ib were successfully isolated and purified from the crude extract of the seeds of a traditional Chinese medicinal plant Aesculus chinensis Bge (Hippocastanaceae) by preparatory high performance liquid chromatography (Pre-HPLC). The gradient mobile phase solvent system composed of methanolwater- acetic acid was employed. An efficient large scale preparatory method was developed based on the stability investigation of escin la for the first time. A total amount of 5.2 g escin la, 2.8 g isoescin la, 3.8 g escin Ib, and 1.6 g isoescin Ib, separately, over 99% purity was obtained from 50 g of total saponins. The preparatory purification of four isomeric saponins by Pre-HPLC was completed in 120 min in a one step separation. [ABSTRACT FROM AUTHOR]