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Chiral amines are valuable building blocks in the manufacture of agrochemicals, pharmaceuticals, natural products, fine chemicals, functional materials among others. Compared to asymmetric hydrogenation of imines/enamides and biocatalytic/organocatalytic asymmetric reductive amination, transition metal catalyzed direct asymmetric hydrogenative amination reactions (DAHA) using molecular dihydrogen as the reductant are highly economical, atom and/or step‐efficient and thus attractive for researchers from both industry and academia. In previous reviews, catalysts/methods development, applications in synthesis of pharmaceuticals and [N] source were summarized and discussed. In this review, we summarize and discuss the ketone substrates scope upon utilizing the state‐of‐the‐art transition metal catalysts. The substrate limitations, potential applications and key mechanisms are also critically concluded. [ABSTRACT FROM AUTHOR]

Heterogeneous photocatalysis has emerged as a powerful and sustainable technique in organic synthesis; however, the application of graphitic carbon nitride (g-C3N4) as a heterogeneous photocatalyst for organic transformations is still in its infancy. The development of novel organic transformations catalyzed by g-C3N4 is actively being pursued by chemists but it remains challenging. Herein, we describe a visible-light-driven g-C3N4-catalyzed atom transfer radical addition (ATRA) of alkynes to synthesize valuable (E)-β-thio/seleno vinylsulfones. This approach features heterogeneous photocatalysis, excellent regio- and stereoselectivities, 100% atom economy, a metal- and additive-free nature, and broad substrate scope covering (hetero)aryl and alkyl alkynes, especially the industrial feedstock propyne. Furthermore, this method can be applied to the late-stage functionalization of complex molecules. Notably, g-C3N4 can be recovered and reused in five runs without loss of catalytic activity. Mechanistic studies demonstrate that the reaction occurs via an energy transfer process rather than single electron transfer. [ABSTRACT FROM AUTHOR]

Arene hydrogenation is the most straightforward method to prepare carbo‐ and heterocycles. However, the high resonance energy prevents aromatic substrates from hydrogenation. Herein the homogeneous, nucleophilic hydrogenation of less electron‐rich arenes and heteroarenes is reported. The Co(P4N2)H species that has been demonstrated to be a strong hydride donor could deliver a hydride ion to the cyano (hetero)arene substrates. Deuterium labeling experiments supported a Michael‐type reaction pathway. Theoretical analyses have been conducted to investigate the hydricity of the catalytically active CoH species and the electrophilicity of the arene substrates. An outlook for the synthesis of more challenging substituted benzenes was proposed based on the in silico modification of the CoH species. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) is a major angiogenic factor involved in a number of pathological processes, including neovascularization, a crucial step in the development of solid malignancies. The aim of this study was to investigate the association of polymorphisms in the VEGF gene with susceptibility to epithelial ovarian cancer (EOC).This case-control study included 303 EOC patients and 303 healthy controls. Genotyping of the VEGF gene polymorphisms at -460C/T, -1154G/A, -2578C/A, and +936C/T were performed by polymerase chain reaction and restriction fragment length polymorphism analysis.No significant difference was found in allele and genotype distributions of the -460C/T, +936C/T, and -2578C/A polymorphisms between patients and controls. However, the frequencies of -1154G/A genotype and allele were significantly different between the two groups (P = 0.037, P = 0.013). Compared with the G/A + A/A genotype, the G/G genotype could significantly increase the risk of developing EOC (odds ratio, 1.64; 95% confidence interval, 1.12-2.39). The haplotype analysis suggested that the -460T/-1154A/-2578C haplotype exhibited a decrease in the risk of developing EOC compared with the -460T/-1154G/-2578C haplotype (odds ratio, 0.644; 95% confidence interval, 0.415-0.999).The study suggested a possible association between the VEGF -1154G/A polymorphism with susceptibility to EOC, but there is no support for an association of the VEGF -460C/T, +936C/T, and -2578C/A polymorphisms with the risk for EOC. [ABSTRACT FROM AUTHOR]

Arene hydrogenation is the most straightforward method to prepare carbo- and heterocycles. However, the high resonance energy prevents aromatic substrates from hydrogenation. Herein the homogeneous, nucleophilic hydrogenation of less electron-rich arenes and heteroarenes is reported. The Co(P 4 N 2 )H species that has been demonstrated to be a strong hydride donor could deliver a hydride ion to the cyano (hetero)arene substrates. Deuterium labeling experiments supported a Michael-type reaction pathway. Theoretical analyses have been conducted to investigate the hydricity of the catalytically active CoH species and the electrophilicity of the arene substrates. An outlook for the synthesis of more challenging substituted benzenes was proposed based on the in silico modification of the CoH species., (© 2022 Wiley-VCH GmbH.)

We have developed a method for recyclable hypervalent-iodine-mediated direct dehydrogenative α,β'- bifunctionalization of β-ketoesters and β-diketones under metal-free conditions, which affords a straightforward way to synthesize benzo-fused 2,3-dihydrofurans. This efficient, mild method, which has a wide substrate scope and good functional-group tolerance, was used for the multistep synthesis of the protected aglycone of a naturally occurring phenolic glycoside. A mechanism involving Michael addition to an enone intermediate and subsequent oxidative cyclization is proposed., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two hexanuclear clusters, [Pt(2)Ag(4)(C≡CC(6)H(4)R)(8)] (R = CH(3), 1; R = H, 2), together with dimer [Pt(2)Ag(4)(C≡CC(6)H(5))(8)](2) (3), have been synthesized and characterized by elemental analyses, electrospray ionization mass spectrometry, and (1)H NMR spectroscopy and by X-ray crystallography for 1 and 3. A considerable enhancement of photoluminescence (PL) and a notable red shift in the emission maximum of 1 (λ(max) 600 nm) relative to 2 (λ(max) 545 nm) are observed. Electrogenerated chemiluminescence (ECL) of 1 and 2 in the absence or presence of coreactant tri-n-propylamine (TPrA) or 2-(dibutylamino)ethanol (DBAE) at different working electrodes in different solvents (CH(2)Cl(2), CH(2)ClCH(2)Cl, or CH(3)CN) has been studied. The ECL spectra are identical with the PL spectra, indicating that ECL emissions are also due to a MLM'CT [Pt(d)/π (C≡CC(6)H(4)R-4) → Pt(p(z))/Ag(sp)/π* (C≡CC(6)H(4)R-4)] state modified by Pt···Ag and Ag···Ag contacts. ECL of 1- and 2/amine systems in CH(2)ClCH(2)Cl was produced at the potentials of 1.14-1.19 V vs SCE, notably negatively shifted by about 0.38 V compared to those of the Ru(bpy)(3)(2+)/amine system. In all cases, ECL quantum efficiencies of 2 are higher than those of 1 and on the same order of magnitude as that of the [Ru(bpy)(3)](PF(6))(2)/amine system. It is noted that Sudan I tends to decrease the ECL intensity of the 1/DBAE system in CH(2)ClCH(2)Cl at a platinum working electrode. A new ECL method for the determination of Sudan I was developed with a linear range of 2.5 × 10(-5)-1.0 × 10(-3) M and a detection limit of 8.0 × 10(-6) M based on 3 times the ratio of signal-to-noise.

Background and Aim: The FAS and FASL system play an important role in regulating apoptotic cell death. This study was designed to investigate the correlation of FAS-1377 G/A, -670 A/G and FASL-844 T/C polymorphisms with susceptibility to gastric cardiac adenocarcinoma in a population of a high-incidence region of Hebei Province., Methods: FAS-1377 G/A, -670 A/G and FASL-844 T/C polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis in 262 gastric cardiac carcinoma (GCA) patients and 524 healthy controls., Results: Family history of upper gastrointestinal cancer (UGIC) might increase the risk of developing GCA (age- and sex-adjusted odds ratio [OR] = 1.38, 95% confidence interval [CI] = 1.02-1.86). The overall allelotype and genotype distributions of FAS-1377 G/A, and FASL-844 T/C polymorphisms in GCA patients did not significantly differ from that in healthy controls (P > 0.05). Compared with individuals with a FAS-670 A/A genotype, individuals with an A/G genotype in a smoker group had a lower risk of developing GCA (age, sex, and family history of UGIC adjusted OR = 0.55, 95% CI = 0.34-0.88). When the genotypes of FAS and FASL single nucleotide polymorphisms (SNP) were combined to analyze, no significant correlation was found between these SNP and the risk for GCA development., Conclusion: In the high-incidence region of Hebei Province, FAS-1377 G/A and FASL-844 T/C polymorphisms were not associated with the risk of GCA. However, the FAS-670 A/G genotype might decrease the risk of GCA for smoker individuals.

Background: Vascular endothelial growth factor (VEGF) plays an important role in the development of endometriosis. The aim of this study was to investigate the association of polymorphisms in the VEGF gene with the susceptibility to endometriosis., Methods: This study comprised 344 North Chinese women with endometriosis and 360 healthy women without endometriosis recruited as control. Genotyping of the VEGF gene polymorphisms at -460C/T, -1154G/A, -2578C/A and +936C/T were performed by PCR and restriction fragment length polymorphism analysis., Results: No significant difference was found in allele and genotype distributions of the -460C/T, +936C/T polymorphisms between patients and controls. However, the frequencies of -1154G/A, -2578C/A genotype and allele were significantly different between the two groups (all P-value <0.013). The -2578A/A, -1154A/A genotypes were found less frequently in patients with endometriosis compared with controls. The haplotype distributions derived from three polymorphisms (-2578C/A, -1154G/A, -460C/T) differed between the two groups (P = 0.000)., Conclusions: The VEGF-460/-1154/-2578 TGC, CAA, TAA and TAC haplotypes were associated with endometriosis. The -1154A and -2578A alleles may be protective against the development of endometriosis in North Chinese women.

Objective: To investigate the association of single nucleotide polymorphisms (SNPs) in VEGF gene with the risk of endometriosis and adenomyosis., Methods: Genotypes were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 344 endometriosis patients, 174 adenomyosis patients, 360 frequency-matched control women of endometriosis and 199 frequency-matched control women of adenomyosis., Results: No significant difference was found in allele frequencies and genotype distributions of the -460C/T polymorphism between patients (endometriosis and adenomyosis) and control women (all P value > 0.05). However, there were significant differences in genotype and allele distributions of the VEGF -1154G/A polymorphism between patients (endometriosis and adenomyosis) and control women (all P value < 0.05). The genotype frequencies of the VEGF -1154 AA, GA, and GG in endometriosis patients and control women were 1.7%, 28.8%, 69.5% and 5.8%, 32.8%, 61.4%, respectively; and the A and G allele frequencies in the two groups were 16.1%, 83.9% and 22.2%, 77.8%, respectively. The genotype frequencies of the VEGF -1154 AA, GA, and GG in adenomyosis patients and control women were 2.9%, 23.6%, 73.6% and 7.0%, 34.2%, 58.8%, respectively; and the A and G allele frequencies in the two groups were 14.7%, 85.3% and 24.1%, 75.9% respectively. Compared with GA+ AA genotype, GG genotypes could significantly increase the risk of endometriosis (OR:1.43,95%CI:1.05-1.96) and adenomyosis (OR:1.95,95%CI:1.26-3.03)., Conclusion: The VEGF -1154G/A polymorphism was associated with susceptibility to endometriosis and adenomyosis, and the GG genotype could significantly increase the risk of developing endometriosis and adenomyosis. However, the VEGF -460C/T polymorphism was not associated with susceptibility to endometriosis and adenomyosis in the population studied.