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Zinc-coordinated conjugated microporous polymers (Zn-CMPs), prepared by linking salen zinc and 1,3,5-triethynylbenzene, exhibit extraordinary activities (turnover frequencies of up to 11600 h(-1) ), broad substrate scope, and group tolerance for the synthesis of functional organic carbonates by coupling epoxides with CO2 at 120 °C and 3.0 MPa without the use of additional solvents. The catalytic activity of Zn-CMP is comparable to those of homogeneous catalysts and superior to those of other heterogeneous catalysts. This catalyst could be reused more than ten times without a significant decrease in performance.

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Compared to the aza-Wittig reaction of aldehydes, ketones, amides and esters, the aza-Wittig reaction of acid anhydride was always overlooked, which should be important part of Wittig reactions. Here, aza-Wittig reaction of anhydride and catalytic aza-Wittig reaction of anhydride were both developed with high yields, which provides an efficient method to synthesize of 4H-benzo[d][1,3]oxazin-4-ones and 4-benzylidene-2-aryloxazol-5(4H)-ones. The strategy of copper-catalyzed reduction of phosphine oxide was used and found effective for this transformation. Additionally, the one-pot catalytic aza-Wittig reaction of carboxylic acids was achieved. Furthermore, NMR experiments and Hammett plot recorded the process of catalytic aza-Wittig reaction of anhydride, which provides direct proof that the copper-catalyzed reduction of waste phosphine oxide is the key step in this transformation.

This paper reports the tandem reaction strategy of the Passerini/Staudinger/aza-Wittig reaction based on the in situ capture of isocyanides. According to this strategy, isocyanides are synthesized in situ and immediately work as the substrate for the Passerini reaction and postmodification tandem reaction in one pot. In addition, two types of new compounds, 5-oxo-3,5-dihydrobenzo­[e]­[1,4]­oxazepines and 6-oxo-5,6-dihydro-2H-1,4-oxazines, were synthesized using the tandem reaction strategy that includes five-step transformations in one pot.

Trametenolic acid B (TAB), the bioactive component in the Trametes lactinea (Berk.) Pat, was reported to possess cytotoxic activities and thrombin inhibiting effects. This study was performed to investigate the effects of TAB on H(+)/K(+)-ATPase and gastric cancer. The H(+)/K(+)-ATPase inhibitory activity was determined by gastric parietal cells. Compared to the normal control group, TAB (10, 20, 40 and 80 μg/mL) inhibited the H(+)/K(+)-ATPase activity by 15.97, 16.96, 24.86 and 16.25%, respectively. In the study, 36 Kunming mice were randomly divided into six groups: control, model, TAB-L (TAB, 5 mg/kg/day, i.g.), TAB-M (TAB, 20 mg/kg/day, i.g.), TAB-H (TAB, 40 mg/kg/day, i.g.) and omeprazole (OL, 10 mg/kg/day, i.g.). All mice except the control group were administrated with anhydrous alcohol (5.0 mL/kg, i.g.) for induced gastric-ulcer 1h after the 5th day. At the same time, the control mice were given the same volume of physiological saline. After 4h, TAB was evaluated for H(+)/K(+)-ATPase inhibitory activities of ulcerative gaster, gastric ulcer index and ulcer inhibition. In vitro, the anti-proliferation effect of TAB to gastric cancer cell (HGC-27) in acid environment was detected by MTT, and the apoptosis morphological changes were also observed by Hoechst 33258 dye assay. The results indicated that TAB inhibited moderately H(+)/K(+)-ATPase activity in vitro. Compared to the model group, TAB showed anti-ulcer effects in gastric tissue with the dosages of 20 and 5 mg/kg in vivo. Apart from that, TAB could selectively inhibit gastric cancer cell viability and reduce cell apoptosis against HGC-27 cells at low doses in acid environment.

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