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The copper catalyzed cyclization of diazoesters in the presence of a chiral spirobisoxazoline ligand proceeds under mild conditions to give the title compounds with high enantioselectivities. [ABSTRACT FROM AUTHOR]

The present study quickly identified the ginsenosides in fresh Panax ginseng and specified the effects of different drying methods(50 ℃-drying, 80 ℃-drying, and-70 ℃ freeze-drying) on ginsenosides.Three P.ginseng products by different drying methods were prepared, and the UHPLC-Q-Exactive Orbitrap high-resolution liquid mass spectrometry(MS) technique was applied to perform gradient elution using water-acetonitrile as the mobile phase, and the data collected in the negative ion mode were analyzed using X Calibur 2.2.The results showed that 57 saponins were identified from fresh P.ginseng.As revealed by the comparison with the fresh P.ginseng, in terms of the loss of ginsenosides, the dried products were ranked as the dried product at 50 ℃, freeze-dried products at-70 ℃, and the dried product at 80 ℃ in the ascending order.This study elucidated the effects of different drying methods on the types and relative content of ginsenosides, which can provide references for the processing of P.ginseng in the producing areas.

A micro power turbine water aeration system with a water biological base and a sediment biological base was independently developed, aimed at urban water eutrophication. The results showed that the average removal rates of COD, NH+4 -N, TP by the water biological base were 82. 33% , 98. 00% and 54. 73% , respectively; The sediment reduction rate achieved by the sediment biological base could reach 20% within 5 days, and aeration in the overlying water could relieve the nutrient releasing caused by the degradation of organic matter; The effect of nutrient removal and organic matter reduction in sediment by the combined ecological restoration technology was perfect in pilot scale. The average removal rates of COD, NH+4 -N, TP were 52. 0%, 33. 6% and 23.4%, respectively, and the organic content in sediment was reduced from 38. 20% to 12.20% .

Efficient: A copper-catalyzed enantioselective intramolecular insertion of carbenoids into phenolic O-H bonds has been developed. This method can be used for the synthesis of the title compounds in high yields and excellent enantioselectivities under mild and neutral conditions. NaBAr(F)=sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A copper-catalyzed asymmetric intramolecular O-H insertion of ω-hydroxy-α-diazoesters has been accomplished by using chiral spiro bisoxazoline ligands. This highly enantioselective intramolecular O-H insertion reaction provides an efficient approach to a variety of synthetically important chiral 2-carboxy cyclic ethers with different ring sizes as well as substitution patterns.