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An enantioselective Si−H insertion between α‐arylvinyldiazoesters and silanes has been developed by employing rhodium(I)/chiral diene complex as the catalyst. This protocol offers a catalytic asymmetric approach to various chiral silanes containing α‐arylvinyl functionality at room temperature with good enantiocontrol (89–99% ee). Transformation of the resulting enantiomerically enriched α‐arylvinyl‐α‐silyl esters led to a variety of other valuable building blocks. The deuterium kinetic isotope effect experiments revealed a rhodium(I)‐mediated concerted Si−H insertion mechanism. [ABSTRACT FROM AUTHOR]

AimsSubarachnoid hemorrhage (SAH) is a devastating stroke subtype. Following SAH, erythrocyte lysis contributes to cell death and brain injuries. Blockage of the anti-phagocytic receptor Cluster of Differentiation 47 (CD47) enhances phagocyte clearance of erythrocytes, though it has not been well-studied post-SAH. The current study aims to determine whether anti-CD47 treatment can enhance blood clearance after experimental SAH.MethodsThe prechiasmatic blood injection model of SAH was used in mice. Mice were either treated with the CD47-blocking antibody or IgG as control. The effect of the anti-CD47 antibody on blood clearance and neurological function following SAH was determined. Neuroinflammation and neuronal injury were compared between the treatment and control samples on day 1 and day 7 after SAH using flow cytometry, immunofluorescence, Fluoro-Jade C, and Nissl staining, RT-PCR, and Western blot analysis.ResultsCD47-blocking antibody sped-up blood clearance after SAH, and resulted in less neuronal injury and neurological deficits than control samples. Microglia played a role in the anti-CD47 blockade. Following SAH Following SAH, CD47 antibody-treated mice had less neuroinflammation and lower levels of apoptosis compared to controls and both one and 7 days.ConclusionsCD47 antibody treatment has a neuroprotective effect following SAH, by increasing blood clearance rate and reducing brain injury. These findings suggest CD47 antibody treatment may improve SAH patient outcomes.

A simple, broad‐scope rhodium(I)/chiral diene catalytic system for challenging asymmetric intramolecular cyclopropanation of various tri‐substituted allylic diazoacetates was successfully developed. The low coordination state RhI‐complex exhibits an extraordinarily high degree of tolerance to the variation in the extent of substitution of the allyl double bond, thus allowing the efficient construction of a wide range of penta‐substituted, fused‐ring cyclopropanes bearing three contiguous stereogenic centers, including two quaternary carbon stereocenters, in a highly enantioselective manner with ease at catalyst loading as low as 0.1 mol %. The stereoinduction mode of this RhI‐carbene‐directed asymmetric intramolecular cyclopropanation was investigated by DFT calculations, indicating that π‐π stacking interactions between the aromatic rings of chiral diene ligand and diazo substrate play a key role in the control of the reaction enantioselectivity. [ABSTRACT FROM AUTHOR]

whether killer cell immunoglobulin-like receptors (KIRs) and human leukocyte antigens C (HLA-C) are associated with HLA-B27 associated acute anterior uveitis (B27AAU) and idiopathic AAU (IAAU) remains unclear. PCR with sequence-specific primers was used to analyze KIR genes and HLA-C alleles in a Chinese Han population of 196AAU patients and 210 control subjects. The higher frequencies of HLA-C2 and KIR2DL1/HLA-C2 (p =.009 and p =.044, respectively) and the lower frequencies of HLA-C1C1 and HLA-C1 (p =.034 and p =.009, respectively) were observed in B27AAU than control group. The higher frequencies of KIR2DL2 and KIR2DL2/HLA-C1 (p =.009 and p =.044, respectively) and the lower frequencies of KIR2DL3 and KIR2DL3/HLA-C1 (p =.000 and p =.001, respectively) were observed in IAAU than control group. HLA-C2 and KIR2DL1/HLA-C2, KIR2DL2, and KIR2DL2/HLA-C1 might be susceptible for B27AAU and IAAU, respectively. HLA-C1C1 and HLA-C1, KIR2DL3 and KIR2DL3/HLA-C1 might protect from B27AAU and IAAU, respectively. [ABSTRACT FROM AUTHOR]

Front Cover: Catalyst- and Light-free S-H Insertion between Phosphorodithioic Acids and Diazo Compounds: Rapid Access to Dialkylphosphorodithioates (Asian J. Org. Keywords: diazo compound; pesticide; phosphorodithioate; phosphorodithioic acid; S-H insertion EN diazo compound pesticide phosphorodithioate phosphorodithioic acid S-H insertion 1 1 1 07/27/23 20230701 NES 230701 B C-S bond formation b has attracted considerable interest for a long time. The cover picture shows a straightforward and efficient C-S bond formation reaction via S-H insertion of phosphorodithioic acids with diazo compounds under catalyst-, and light-free conditions. [Extracted from the article]

A rhodium(I)-diene catalyzed highly enantioselective C(sp 2 )-H functionalization of simple unprotected indoles, pyrroles, and their common analogues such as furans, thiophenes, and benzofurans with arylvinyldiazoesters has been developed for the first time. This transformation features unusual site-selectivity exclusively at the vinyl terminus of arylvinylcarbene and enables a reliable and rapid synthetic protocol to access a distinctive class of diarylmethine-bearing α,β-unsaturated esters containing a one or two heteroarene-attached tertiary carbon stereocenter in high yields and excellent enantioselectivities under mild reaction conditions. Mechanistic studies and DFT calculations suggest that, compared to the aniline substrate, the more electron-rich indole substrate lowers the C-C addition barrier and alters the rate-determining step to the reductive elimination, leading to different isotope effect., (© 2022 Wiley-VCH GmbH.)