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Herein, we describe an unprecedented cascade reaction to β-stereogenic γ-lactams involving Pd(II)-catalyzed enantioselective aliphatic methylene C(sp3 )-H alkenylation-aza-Wacker cyclization through syn-aminopalladation. Readily available 3,3'-substituted BINOLs are used as chiral ligands, providing the corresponding γ-lactams with broad scope and high enantioselectivities (up to 98 % ee).

Atropisomeric anilides have received tremendous attention as a novel class of chiral compounds possessing restricted rotation around an N-aryl chiral axis. However, in sharp contrast to the well-studied synthesis of biaryl atropisomers, the catalytic asymmetric synthesis of chiral anilides remains a daunting challenge, largely due to the higher degree of rotational freedom compared to their biaryl counterparts. Here we describe a highly efficient catalytic asymmetric synthesis of atropisomeric anilides via Pd(II)-catalyzed atroposelective C-H olefination using readily available L-pyroglutamic acid as a chiral ligand. A broad range of atropisomeric anilides were prepared in high yields (up to 99% yield) and excellent stereoinduction (up to >99% ee) under mild conditions. Experimental studies indicated that the atropostability of those anilide atropisomers toward racemization relies on both steric and electronic effects. Experimental and computational studies were conducted to elucidate the reaction mechanism and rate-determining step. DFT calculations revealed that the amino acid ligand distortion is responsible for the enantioselectivity in the C-H bond activation step. The potent applications of the anilide atropisomers as a new type of chiral ligand in Rh(III)-catalyzed asymmetric conjugate addition and Lewis base catalysts in enantioselective allylation of aldehydes have been demonstrated. This strategy could provide a straightforward route to access atropisomeric anilides, one of the most challenging types of axially chiral compounds.

Herein, we describe an unprecedented cascade reaction to β-stereogenic γ-lactams involving Pd(II)-catalyzed enantioselective aliphatic methylene C(sp

An efficient strategy for N/O-(deutero)alkylation of indoles and phenols with alkoxides/alcohols as the alkylation reagents is described. The consecutive detosylation/alkylation transformations feature mild reaction conditions, high ipso-selectivity, and good functional group tolerance (>50 examples). A one-pot selective N-alkylation of unprotected indoles with alcohols and TsCl is also realized. The application of this method is demonstrated by the introduction of isotope-labeled (CD3 and 13CH3) groups using the readily accessible labeled alcohols and the synthesis of pharmaceuticals.

It is challenging to develop simple and low cost catalytic systems while maintaining high reactivity and selectivity. An iron-catalyzed intramolecular C-H amination of sulfamate esters using simple and cheap ligands is reported with general substrate scope (31 examples, up to 95% yield). The addition of second ligand, bipyridine, is able to accelerate the reaction and increase the yield. The ready availability of these iron catalysts provides a promising approach to selective introduction of nitrogen into hydrocarbon feedstock.

Vernalization requirement is an important characteristic in crop breeding. Wheat is a widely grown crop in the world that possesses enormous economic significance. To better understand the gene networks in vernalization process, we performed a high-throughput RNA sequencing analysis comparing the transcriptomes of spring and winter wheat cultivars, with and without vernalization (unpublished data). In this study, we selected six unigenes (CL14010, CL12788, CL176, Unigene 16777, CL8746 and Unigene10196) from our transcriptome analysis based on their expression differences to further characterize their function. Transient silencing of the six unigenes individually were achieved through virus-induced gene silencing (VIGS) using BSMV vector. The period from germination to spike differentiation were recorded and compared between plants underwent VIGS silencing and the control. Our result showed that VIGS of the six unigenes significantly shortened the period from seedling to double ridge (DR) stage. Resulting in SD period ranging from 59.8 ± 0.60 to 65.8 ± 0.48 days, compared to 85.0 ± 0.73 days in the control. The results indicated that these six unigenes function as suppressors in vernalization process and silence or down-regulation of these genes promoted flower development in wheat. Further characterization of these six unigenes and their function in vernalization and flowering control is needed.

To study the effects of Jiawei Huzhang San (JWHZS) decoction on the expressions of the inflammatory factors monocyte chemoattractant protein-1 (MCP-1) and platelet-derived growth factor-BB (PDGF-BB) on experimental autoimmune prostatitis in rats.Twelve male Wistar rats were taken as normal controls, and models of experimental autoimmune prostatitis were established in another 60 by injection of SC purified prostate protein with FCA, and then divided into five groups to be treated with normal saline, indomethacin, high-dose JWHZS (0.445 g/kg), medium-dose JWHZS (0.223 g/kg) and low-dose JWHZS (0.089 g/kg), respectively. All the rats were sacrificed at 30 days after the treatment for detection of the mRNA and protein expressions of inflammatory factors by immunohistochemistry and fluorescent quantitative RT-PCR.In the high-, medium- and low-dose JWHZS groups, the mRNA expressions of MCP-1 (0.31 +/- 0.14, 0.49 +/- 0.21 and 0.62 +/- 0.28) and PDGF-BB (0.50 +/- 0.22, 0.54 +/- 0.17 and 0.71 +/- 0.29), and the protein expressions of MCP-1 (677 +/- 208, 725 +/- 311 and 1302 +/- 884) and PDGF-BB (1265 +/- 698, 1347 +/- 827 and 1655 +/- 812) were significantly lower than in the model control group (MCP-1 mRNA: 1.12 +/- 0.43; MCP-1 protein: 2201 +/- 934; PDGF-BB mRNA: 1.14 +/- 0.51; PDGF-BB protein: 2754 +/- 852) (P0.05). And JWHZS exhibited a significantly better activity at high and medium doses than at a low dose (P0.05). In the indomethacin control group, both the mRNA and protein expressions of MCP-1 (0.71 +/- 0.34 and 1824 +/- 1157) and PDGF-BB (1.08 +/- 0.37 and 2493 +/- 924) were markedly higher than in the JWHZS groups (P0.01).Down-regulation of the inflammatory factors MCP-1 and PDGF-BB may be the important molecular mechanism of JWHZS acting on experimental autoimmune prostatitis.