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"Through space" metal/hydrogen shift constitutes one of the efficient elementary step in organometallic chemistry to achieve selective remote C−H bond functionalization. Compared with the relatively extensive exploration on 1,4‐palladium migration, the processes on corresponding 1,5‐palladium translocation are far less explored. Based on our understanding on related research areas, we summarized the advances achieved in remote C−H bond activation through a key step of 1,5‐palladium migration in this minireview. The background, reaction scope, and more importantly, the mechanistic rationale of each transformation was discussed. We hope by reading through this minireview, one could get a general perspective on direct C−H bond activation via 1,5‐palladium/hydrogen shift, and could understand why such a process is less common when compared with the process going through 1,4‐palladium/hydrogen migration, and eventually could be inspired to develop practical ways for the synthesis of valuable molecules, which could not be prepared easily through other traditional approaches. [ABSTRACT FROM AUTHOR]

"Through space" palladium/hydrogen shift is an efficient strategy to achieve selective functionalization of a specific remote C−H bond. Compared with relatively extensive exploited 1,4‐palladium migration process, the relevant 1,5‐Pd/H shift was far less investigated. We herein report a novel 1,5‐Pd/H shift pattern between a vinyl and an acyl group. Through the pattern, rapid access to 5‐membered‐dihydrobenzofuran and indoline derivatives has been achieved. Further studies have unveiled an unprecedented trifunctionalization (vinylation, alkynylation and amination) of a phenyl ring through 1,5‐palladium migration relayed decarbonylative Catellani type reaction. A series of mechanistic investigations and DFT calculations have provided insights into the reaction pathway. Notably, it was unveiled that the 1,5‐palladium migration in our case prefers a stepwise mechanism involving a PdIV intermediate. [ABSTRACT FROM AUTHOR]

A reagent-free intramolecular dehydrogenative C–N cross-coupling reaction has been developed under mild electrolytic conditions. In this atom- and step-economical one-pot process, valuable 1,2,4-triazolo[4,3-a]pyridines and related heterocyclic compounds could be synthesized efficiently from commercially available aliphatic or (hetero)aromatic aldehydes and 2-hydrazinopyridines. Various functional groups are compatible with this metal- and oxidant-free protocol which can be carried out on a gram scale easily. This novel method was applied to the synthesis of one of the top-selling drugs Xanax and late stage functionalization for generating chemical diversity in biologically relevant lead molecules. [ABSTRACT FROM AUTHOR]

A simple and efficient method was developed for the construction of the medicinally important 3-substituted-3-hydroxyoxindole and its 3-spirocyclic derivatives with readily available aniline derivatives as starting materials. This highly atom- and step-economical one-pot protocol was carried out under metal-free base-mediated conditions through a novel oxidative annulation strategy with oxygen as the oxidant. The key intermediates were isolated and confirmed. A reasonable reaction pathway was proposed and supported by the preliminary experiments, and the computational studies were carried out to understand the energetics of the key rearrangement reaction. [ABSTRACT FROM AUTHOR]

Abstract: 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 80μg/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, 5mg/kg/day, i.g.), TAB-M (TAB, 20mg/kg/day, i.g.), TAB-H (TAB, 40mg/kg/day, i.g.) and omeprazole (OL, 10mg/kg/day, i.g.). All mice except the control group were administrated with anhydrous alcohol (5.0mL/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 5mg/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. [Copyright &y& Elsevier]

Here, we describe a highly selective Pd-catalyzed C(sp 3 )-H biarylation of 2-methylbenzaldehydes using cyclic diaryliodonium salts as arylation reagents. The key strategy is the employment of tert -leucine as a bidentate transient directing group for the proximity-driven metalation to achieve reactivity and selectivity in C-H activation. Various functionalized biaryls bearing both aldehyde and iodine functional groups were prepared successfully, which could be further transformed into a wide range of compounds with potential applications in pharmaceutical chemistry and materials science.

A simple and efficient method was developed for the construction of the medicinally important tetracyclic 3-spirooxindole benzofuranones. In this highly atom- and step-economical one-pot protocol, one quaternary carbon center, two new cycles, and four new bonds (C-C/C-O/C-N) were formed under simple ligand-free copper-catalyzed conditions through a novel tandem oxidative annulation strategy.

A novel one-pot procedure is described for the transition-metal catalyzed sequential difunctionalization of diaryliodonium reagents. Reaction of commercially available anthranilic acid derivatives with readily available cyclic diaryliodonium salts followed by a Sonogashira coupling afforded various alkyne substituted biaryls in good to excellent yields. The functionalized biaryls were then utilized for the rapid and efficient one-pot synthesis of novel poly(hetero)aryl containing 10-membered lactones which are potential G-quadruplex binders and telomerase inhibitors.

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., (Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.)

In the title compound, C(15)H(24)O(4), 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 mol-ecules into chains running along the a-axis direction.