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Hydrogen gas (H2) has attracted attention as a next-generation clean energy source. Its efficient and safe preparation and utilization are crucial in both the industry and organic chemistry research. In this study, a Pt/CB (platinum on carbon bead)-catalyzed MW-mediated continuous-flow hydrogenation reaction was developed using methylcyclohexane (MCH) as the reducing agent (hydrogen carrier). Alkynes, alkenes, nitro groups, benzyl esters, and aromatic chlorides were chemoselectively hydrogenated using Pt/CB under MW-assisted continuous-flow conditions. This methodology represents a safe and energy-efficient hydrogenation process, as it eliminates the need for an external hydrogen gas supply or heating jackets as a heating medium. The further application of MW-mediated continuous-flow hydrogenation reactions is a viable option for the efficient generation and utilization of sustainable energy. [ABSTRACT FROM AUTHOR]

The first atroposelective Chan–Lam coupling for the synthesis of C–N axial enantiomers is reported with good yields and ee. MnO2 additive is crucial for the success of the coupling. The longstanding problem of the lack of enantioselective synthesis to make chiral C–N linked atropisomers is solved. [ABSTRACT FROM AUTHOR]

The active form of vitamin D3, 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3], is a major regulator of calcium homeostasis through activation of the vitamin D receptor (VDR). We have previously synthesized vitamin D derivatives with large adamantane (AD) rings at position 24, 25, or 26 of the side chain to study VDR agonist and/or antagonist properties. One of them—ADTK1, with an AD ring and 23,24-triple bond—shows a high VDR affinity and cell-selective VDR activity. In this study, we synthesized novel vitamin D derivatives (ADKM1-6) with an alkyl group substituted at position 25 of ADTK1 to develop more cell-selective VDR ligands. ADKM2, ADKM4, and ADKM6 had VDR transcriptional activity comparable to 1,25(OH)2D3 and ADTK1, although their VDR affinities were weaker. Interestingly, ADKM2 has selective VDR activity in kidney- and skin-derived cells—a unique phenotype that differs from ADTK1. Furthermore, ADKM2, ADKM4, and ADKM6 induced osteoblast differentiation in human dedifferentiated fat cells more effectively than ADTK1. The development of vitamin D derivatives with bulky modifications such as AD at position 24, 25, or 26 of the side chain is useful for increased stability and tissue selectivity in VDR-targeting therapy. [ABSTRACT FROM AUTHOR]

4,5,6,7-Tetrahydroisobenzofurans, corresponding to the AC(D)E ring structure of viridin and equipped with required substituents on the A-ring, were synthesized with high regio- and stereoselectivities via the Diels–Alder adduct of a furan derivative and maleic anhydride. The key steps of this work include the regioselective opening of a tetrahydrofuran ring, a stereoselective epoxidation, and an AlMe3-mediated regioselective epoxide opening followed by stereoselective C-methylation. [ABSTRACT FROM AUTHOR]

The front cover of the journal "Advanced Synthesis & Catalysis" features an illustration of pandas as gold catalysts on trees, representing the 5¿exo¿dig¿selective cyclization of ¿,ß¿ynones. The illustration highlights the synthesis of 2¿exomethylene indolin¿3¿ones, which can be used to create spiropseudoindoxyl and pyranoindole derivatives. The image suggests that these synthetic materials could have potential applications in the development of new bioactive substances. The details of this research can be found in an article by Tsuyoshi Yamada and co-authors. [Extracted from the article]

Starting from readily available tertiary alcohols, four different reactions (a 1,3-migration of a hydroxy group, kinetic resolution, racemization, and an intramolecular Diels–Alder reaction) took place under co-catalysis by lipase and oxovanadium compounds in a one-pot process to produce polysubstituted tricyclic carbon frameworks in high yields and with high enantioselectivities. The key to the success of this process was the discovery that a silyl group attached to the terminal carbon of the vinyl moiety completely controls the direction of hydroxy group migration [ABSTRACT FROM AUTHOR]

Interleukin (IL)-18 is an interferon γ-inducing inflammatory cytokine associated with function of the immune system and other physiological functions. IL-18-deficient (Il18-/-) mice exhibit obesity, dyslipidemia, non-alcoholic steatohepatitis and depressive-like behavioral changes. Therefore, IL-18 has a number of important roles associated with immunity, energy homeostasis and psychiatric conditions. In the present study, gene expression in the brains of Il18-/- mice was analyzed to identify genes associated with the depressive-like behaviors and other impairments displayed by Il18-/- mice. Using whole genome microarray analysis, gene expression patterns in the brains of Il18+/+ and Il18-/- mice at 6 and 12 weeks of age were examined and compared. Subsequently, genes were categorized using Ingenuity® Pathway Analysis (IPA). At 12 weeks of age, 2,805 genes were identified using microarray analysis. Genes related to 'Major depression' and 'Depressive disorders' were identified by IPA core analysis, and 13 genes associated with depression were isolated. Among these genes, fibroblast growth factor receptor 1 (Fgfr1); protein tyrosine phosphatase, non-receptor type 1 (Ptpn1); and urocortin 3 (Ucn3) were classed as depression-inducing and the other genes were considered depression-suppressing genes. Subsequently, the interactions between the microarray results at 6 weeks of age and the above three depression-inducing genes were analyzed to search for effector genes of depression at 12 weeks of age. This analysis identified cyclin D1 (Ccnd1) and NADPH oxidase 4 (Nox4). The microarray analysis results were correlated with the results of reverse transcription-quantitative PCR (RT-qPCR). Overall, the results suggest that Fgfr1, Ptpn1 and Ucn3 may be involved in depression-like changes and Ccnd1 and Nox4 regulate these three genes in IL-18-deficient mice. [ABSTRACT FROM AUTHOR]

A monodentate biaryl phosphine-Pd catalyst is used for studying the amidation of aryl halides and sulfonates. The utilization of ligands possessing a methyl group ortho to the phosphorous center has allowed a variety of aryl and heteroaryl chlorides with various amides to be coupled in high yield.