Pd(0)/Xantphos-Catalyzed Benzylic C(sp)-O Arylation of Benzyl Heteroaryl Ethers: Reduction of Pd(II) to Pd(0) by Xantphos.

Herein, we report the synthesis of 1,1-diarylmethanes via palladium-catalyzed benzylic C(sp)-O arylation of benzyl alcohol derivatives. An efficient, straightforward approach to synthesizing Pd(0)(xantphos) was developed through in situ reduction of Pd(II) to Pd(0) with the bidentate tertiary phosphine xantphos, which proved to be a highly active precatalyst in the Suzuki-Miyaura cross-coupling reaction of benzyl heteroaryl ethers.

Palladium-Catalyzed -Selective C-H Olefination and Acetoxylation of Benzylamines Enabled by an Unmasked Benzoyl Template.

Benzylamines belong to an important class of building blocks in the synthesis of biologically active natural products and drugs. Encumbered by amide-directed -C-H activation, remote -selective C-H functionalization of benzylamines has hitherto not been realized to date. Here, we report a palladium-catalyzed -selective C-H olefination and acetoxylation of benzylamines using a functionalized benzoyl template.

Regiodivergent Remote C-H Functionalization by Tuning Template Geometry.

For transition-metal-catalyzed C-H functionalization, precise differentiation between remote adjacent C(sp)-H bonds remains a long-standing challenge. Here, the template structure-directivity relationship on remote C-H functionalization of arenes was experimentally and computationally studied. By using geometry-tunable templates, Pd-catalyzed remote - and -C-H activation of benzoic acids was achieved with high site selectivity.

Rheumatoid arthritis is a protective factor against Alzheimer's disease: a bidirectional two-sample Mendelian randomization study.

Background: Epidemiological evidence suggests that there is an association between rheumatoid arthritis (RA) and Alzheimer's disease (AD). However, the causal relationship between RA and AD remains unclear. Therefore, this study aimed to investigate the causal relationship between RA and AD.

Macrocyclization remote -selective C-H olefination using a practical indolyl template.

The synthesis of macrocyclic compounds with different sizes and linkages remains a great challenge transition metal-catalysed intramolecular C-H activation. Herein, we disclose an efficient macrocyclization strategy Pd-catalysed remote -C-H olefination using a practical indolyl template. This approach was successfully employed to access macrolides and coumarins.

Deep defects limiting the conversion efficiency of SbSe thin-film solar cells.

Quasi-one-dimensional (Q1D) semiconductor antimony selenide (SbSe) shows great potential in the photovoltaic field, but the photoelectric conversion efficiency (PCE) of SbSe-based solar cells has shown no obvious breakthrough during the past several years, of which the intrinsic reasons are pending experimentally. Here, we prepare high-quality Q1D SbSe thin films the vapor transport deposition technique. By investigating the bandedge electronic level structure and carrier relaxation/recombination dynamics, we find that (i) the optimized Se-rich growth conditions can highly improve the crystal quality of the Q1D SbSe thin films, the carrier lifetime of which is substantially increased up to ∼8.

Continued spring phenological advance under global warming hiatus over the Pan-Third Pole.

The global surface temperature has witnessed a warming hiatus in the first decade of this century, but how this slowing down of warming will impact spring phenology over Pan-Third Pole remains unclear. Here, we combined multiple satellite-derived vegetation indices with eddy covariance datasets to evaluate the spatiotemporal changes in spring phenological changes over the Pan-Third Pole. We found that the spring phenology over Pan-Third Pole continues to advance at the rate of 4.

Theoretical research on reasonable shield support capacity in close-multiple coal seams with the coordinated mining: A case study of Qianjiaying coal mine.

In order to assess the rationality of the rated shield support capacity (RSSC) experienced selection and guide the reasonable RSSC selection for the subsequent working faces of each coal seam, the coupling relationship between shield and roof strata was revealed during each coal seams mining. According to whether the fractured rock blocks generated by the main roof are articulated and whether the upper coal seam has been mined and influenced on the lower coal seam, two roof structure mechanical models of the rock blocks generated by the thick main roof and two calculation methods of a given load on the rock blocks are proposed. In addition, a selection method of roof structure model for maximum shield support capacity (MSSC) of close-multiple coal seams with the coordinated mining is put forward.

Design, synthesis and biological evaluation of dihydro-2-quinolone platinum(iv) hybrids as antitumor agents displaying mitochondria injury and DNA damage mechanism.

The design of novel platinum(iv) complexes with mitochondria injury competence, besides the DNA damage mechanism, is a promising way to develop new platinum drugs. Herein, dihydro-2-quinolone (DHQLO) as a mitocan was incorporated into the platinum(iv) system for the first time to prepare a new series of DHQLO platinum(iv) compounds. Complex 1b could effectively inhibit the proliferation of tumor cells in vitro and in vivo.

A potent aminonaphthalimide platinum(IV) complex with effective antitumor activities in vitro and in vivo displaying dual DNA damage effects on tumor cells.

A new aminonaphthalimide platinum(IV) complex was developed by incorporating aminonaphthalimide, a DNA intercalator, into the platinum(IV) system. This complex displayed potent antitumor activities against all tested tumor cell lines in vitro and showed great potential in overcoming drug resistance of cisplatin. Moreover, it remarkably inhibited the growth of CT26 xenografts in BALB/c mice without severe side effects in vivo.

Heterogeneous sea-level rises along coastal zones and small islands.

Coastal zones and many small islands are highly susceptible to sea-level rise (SLR). Coastal zones have a large exposed population and integrated high-value assets, and islands provide diverse ecosystem services to millions of people worldwide. The coastal zones and small islands affected by SLR are likely to suffer from submergence, flooding and erosion in the future.

[Rapid identification of chemical components in compound Nanxing acesodyne plaster by UPLC-Q-TOF-MS/MS].

The study aims to qualitatively analyze the chemical composition of compound Nanxing acesodyne plaster by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry( UPLC-Q-TOF-MS/MS). The analysis was performed on Agilent Zorbax SB-C_(18)( 4. 6 mm×250 mm,5 μm) column.

Synthesis and evaluation of bi-functional 7-hydroxycoumarin platinum(IV) complexes as antitumor agents.

A series of bi-functional 7-hydroxycoumarin platinum(IV) complexes were synthesized, characterized, and evaluated for antitumor activities. The 7-hydroxycoumarin platinum(IV) complexes display moderate to effective antitumor activities toward the tested cell lines and show much potential in overcoming drug resistance of platinum(II) drugs. In reducing microenvironment, the title compounds could be reduced to platinum(II) complex accompanied with two equivalents of coumarin units.

Development of a series of 4-hydroxycoumarin platinum(IV) hybrids as antitumor agents: Synthesis, biological evaluation and action mechanism investigation.

A series of new 4-hydroxycoumarin platinum(IV) complexes were designed, synthesized and evaluated as antitumor agents. All the title compounds display moderate to effective antitumor activities toward the tested cell lines and two prominent compounds were screened out with activities comparable to cisplatin and oxaliplatin. The mechanism investigation demonstrates that the platinum(IV) compounds could be reduced to bivalence and exert significant genotoxicity to tumor cells.

Design and synthesis of a new series of low toxic naphthalimide platinum(IV) antitumor complexes with dual DNA damage mechanism.

Naphthalimide platinum(IV) antitumor complexes with potential dual DNA damage mechanism were designed, synthesized and evaluated for antitumor activities. The incorporation of DNA targeted naphthalimide group to the platinum(IV) system exerts much positive impacts on their antitumor efficacy. The mechanism research reveals that the title compounds could interact with dsDNA in platinum(IV) form via the naphthalimide group and cause DNA lesion.