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A novel tactic for the regioselective O-alkylation of 2-pyridones has been realized through palladium catalysis facilitated by silver carbonate in moderate to high yields, the coordination effect between palladium and nitrogen on the pyridine ring plays a versatile role.

An effective regiodivergent synthesis toward 1- and 3-thiosugars was achieved through palladium and cobalt catalysis, respectively. β-1-Thiosugars were obtained from 3,4-O-carbonate-glycals and var...

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.

Three new steroidal compounds with polyhydroxy groups, tupisteroide A-C (1-3), were obtained from the roots of Tupistra chinensis, together with one known compound (4) that was isolated from this plant for the first time. The structures of tupisteroide A-C were determined on the basis of one- and two-dimensional NMR spectroscopy, including (1) H-(1) H Correlation Spectroscopy, Heteronuclear Multiple Bond Correlation, and Heteronuclear Single Quantum Coherence experiments. The isolated compounds were evaluated for their cytotoxic activities against A549, HepG2, and CaSki cancer cell lines in vitro. Among them, compounds 1, 2, and 4 did not show significant inhibitory activity, but compound 3 showed cytotoxicity against A549 cancer cell lines with IC(50) values of 25.0 μM.

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.

In the title compound, C15H24O4, the six-membered ring shows a distorted chair conformation and the five-membered ring adopts an envelope conformation with the C atom bearing the methyl and OH groups as the flap. In the crystal, O—H...O hydrogen bonds link the molecules into chains running along the a-axis direction.