Optimization of the processing technology of Fructus Arctii by response surface methodology.

The present study was designed to optimize the processing of Fructus Arctii by response surface methodology (RSM). Based on single factor studies, a three-variable, three-level Box-Behnken design (BBD) was used to monitor the effects of independent variables, including processing temperature and time, on the dependent variables. Response surfaces and contour plots of the contents of total lignans, chlorogenic acid, arctiin, and arctigenin were obtained through ultraviolet and visible (UV-Vis) monitoring and high performance liquid chromatography (HPLC). Fructus Arctii should be processed under heating in a pot at 311 °C, medicine at 119 °C for 123s with flipping frequently. The experimental values under the optimized processing technology were consistent with the predicted values. In conclusion, RSM is an effective method to optimize the processing of traditional Chinese medicine (TCM).

[Study on quality evaluation of cimicifugae rhizoma from different producing areas by HPLC fingerprint].

To establish a fingerprint for Cimicifugae Rhizoma from different producing areas. Column kromasil (4.6 mm x 250 mm, 5 microm) was employed with acetonitrile-0.1% formic acid solution as the mobile phase for gradient elution. The flow rate was 1.0 mL x min(-1), the detection wavelength was 254 nm. Twenty chromatographic peaks were extracted as the common peaks of fingerprint, and 21 batches of samples were compared and classified with such methods as similarity evaluation, cluster analysis and principle component analysis. The results showed 12 common peaks and three categories of samples. The method was so highly reproducible, simple and reliable that it could provide basis for quality control and evaluation of Cimicifugae Rhizoma from different producing areas.

Photoinduced reactions of bicycloalkylidenes with isatin and isoquinolinetrione.

Photoinduced reactions of isatin and N-methyl-1,3,4-isoquinolinetrione with bicycloalkylidenes such as bicyclopropylidene, cyclopropylidenecyclobutane, cyclopropylidenecyclohexane and bicyclohexylidene were investigated. The reactions gave spirooxetanes as the major products derived from the [2 + 2] photocycloaddition pathway via 1,4-biradical recombination. Unusual products including the [4 + 2 + 2] cycloadducts, the oxoisochroman derivatives and other ring-rearranged products were derived from competitive pathways via 1,6-biradical recombination. The presence of oxygen in the reaction solution was found to be relevant to the distribution of different types of products. Mechanisms were proposed to rationalize the chemo- and regioselectivity in the photoreactions and the origin of the different types of products.