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A high-efficient and stereo-specific approach for the preparation of biologically important (E)-2-styryl-tetrahydrobenzo[d]thiazoles has been developed via TMSCl promoted direct sp3 C-H alkenylation of 2-methyl-5,6-dihydrobenzo[d]thiazol-7(4H)-one under metal-free conditions. Seventeen target compounds were synthesized in excellent yields of 82% –98% under the optimal conditions of 300 mol% TMSCl at 110°C for 2 h, and their chemical structures were elucidated by IR, NMR, ESI-MS, elemental analyses and X-ray crystallography analysis. A plausible mechanism was also proposed, and this method provided a good functional group conversion for the sp3 C-H substrates.

Eleven triazolyl substituted tetrahydrobenzofuran derivatives were synthesized in high yields as novel H+/K+-ATPase inhibitor via one-pot CuI-catalyzed three-component click reaction of azide, secondary amine and 3-bromopropyne under mild conditions in water. Their structures were characterized by NMR, IR, ESI-MS, elemental analysis and single-crystal X-ray diffraction analysis. Most of the target compounds exhibited better H+/K+-ATPase inhibitory activity than commercial omeprazole with IC50 values less than 15 µmol·L−1. The initial structure-activity analysis suggested that the triazole substituted by cycloalkyl, aromatic ring or O-containing side-chain seemed to be beneficial for enhancing the activity.

Nine bisabolangelone reduction derivatives were synthesized and separated as potential anti-ulcer agent. Their structures were characterized by 2D NMR, IR, ESI-MS, elemental analysis and single-crystal X-ray diffraction analysis. Preliminarily H+/K+-ATPase activity evaluation indicated that all the target compounds had a certain inhibitory effect, and compounds II and IV exhibited the better inhibitory activity against H+/K+-ATPase than bisabolangelone and the commercial omeprazole with the IC50 of 23.21 and 65.32 μmol/L, respectively. The initial structure-activity analysis suggested that the presence of carbonyl group in six-membered ring and double bond in side-chain seemed to be necessary to the activity.