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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.

"AIM: To evaluate the efficacy and safety of combined intra-arterial chemotherapy (IAC) and intravitreal melphalan (IVM) for the treatment of advanced unilateral retinoblastoma. METHODS: This retrospective study involved 30 consecutive eyes from 30 Chinese patients with advanced unilateral retinoblastoma. All patients were initially treated with IAC combined with IVM. The clinical status and complications were recorded at each visit. RESULTS: The International Intraocular Retinoblastoma Classification groups were D in 23 eyes and E in 7 eyes. All eyes showed severe cloud vitreous seeds at the first visit. The mean number of IAC cycles and intravitreal injections was 3.2 (range, 3-4) and 6 (range, 1-14), respectively. The median follow-up time was 29mo (range, 7-36mo). Treatment success with regression of the retinal tumor and vitreous seeds was achieved in 29 of 30 eyes (96.7%). Globe salvage was attained in 93.3% (28/30) eyes, and enucleation (n=2) was performed due to neovascular glaucoma and persistent vitreous hemorrhage. Complications included retinal pigment epithelium (RPE) atrophy (n=13; 43%), mild lens opacity (n=7; 23%), vitreous hemorrhage (n=5; 17%) and rhegmatogenous retinal detachment (n=1; 3%). No extraocular tumor extension or metastasis occurred. CONCLUSION: Combined IAC and IVM is effective and safe for the treatment of advanced unilateral retinoblastoma."

A catalyst‐ and light‐free S−H insertion of phosphorodithioic acids with diazo compounds has been developed, in which phosphorodithioic acid acts not only as an acid promoter but also as a nucleophile. This protocol features fast reaction rate, broad substrate scope, mild conditions, and simple operation, providing a cost‐effective and general approach to diverse phosphorodithioates. [ABSTRACT FROM AUTHOR]

A simple, efficient, and broad-scope rhodium(I)-catalyzed direct N-arylation of arylazocarboxylates with arylboronic acids has been developed, allowing access to a diverse range of unsymmetrical N,N-diarylhydrazides from readily available starting materials in high yields under extraordinary mild conditions. The reaction features easy operation, ambient temperature and low catalyst loading (as low as 0.1 mol%), as well as broad functional-group compatibility. The resulting N,N-diarylhydrazides could serve as versatile building blocks to furnish other structurally important or pharmaceutically interesting molecules. This protocol provides an attractive and complementary approach for the assembly of valuable N,N-diarylamine scaffolds. [ABSTRACT FROM AUTHOR]

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]

A rhodium(I)‐diene catalyzed highly enantioselective C(sp2)−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. [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]

Main observation and conclusion: Transition‐metal‐catalyzed C—H insertion of metal‐carbene represents an excellent and powerful approach for C—H functionalization. However, despite remarkable advances in metal‐carbene chemistry, transition metal catalysts that are capable of enantioselective intermolecular carbene C—H insertion are mainly constrained to dirhodium(II) and iridium(III)‐based complexes. Herein, we disclose a new version of asymmetric carbene C—H insertion reaction with rhodium(I) catalyst. A highly enantioselective rhodium(I) complex‐catalyzed C(sp3)—H functionalization of 1,4‐cyclohexadienes with α‐aryl‐α‐diazoacetates was successfully developed. By using chiral bicyclo[2.2.2]‐octadiene as ligand, rhodium(I)‐carbene‐induced asymmetric intermolecular C—H insertion proceeds smoothly at room temperature, allowing access to a diverse variety of α‐aryl‐α‐cyclohexadienyl acetates and gem‐diaryl‐containing acetates in good yields with good to excellent enantioselectivities (up to 99% ee). Furthermore, the synthetic utility of the reaction was highlighted by facile synthesis of a novel cannabinoid CB1 receptor ligand. This method may offer a new opportunity for the development of therapeutically exploitable cannabinoid receptor type ligands in medicinal chemistry. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Transition‐metal‐catalyzed C—H insertion of metal‐carbene represents an excellent and powerful approach for C—H functionalization. However, despite remarkable advances in metal‐carbene chemistry, transition metal catalysts that are capable of enantioselective intermolecular carbene C—H insertion are mainly constrained to dirhodium(II) and iridium(III)‐based complexes. Herein, we disclose a new version of asymmetric carbene C—H insertion reaction with rhodium(I) catalyst. A highly enantioselective rhodium(I) complex‐catalyzed C(sp3)—H functionalization of 1,4‐cyclohexadienes with α‐aryl‐α‐diazoacetates was successfully developed. By using chiral bicyclo[2.2.2]‐octadiene as ligand, rhodium(I)‐carbene‐induced asymmetric intermolecular C—H insertion proceeds smoothly at room temperature, allowing access to a diverse variety of α‐aryl‐α‐cyclohexadienyl acetates and gem‐diaryl‐containing acetates in good yields with good to excellent enantioselectivities (up to 99% ee). Furthermore, the synthetic utility of the reaction was highlighted by facile synthesis of a novel cannabinoid CB1 receptor ligand. This method may offer a new opportunity for the development of therapeutically exploitable cannabinoid receptor type ligands in medicinal chemistry. [ABSTRACT FROM AUTHOR]

We have developed a highly effective palladium/PHOX catalyst system for efficient asymmetric 1,2‐addition of arylboronic acids to six‐membered 1,2,6‐thiadiazine‐1,1‐dioxide type cyclic N‐sulfonyl α‐iminoesters. The protocol allows convenient synthesis of a variety of nearly optically pure α‐quaternary amino acid derivatives under mild reaction conditions. The synthetic utility of the reaction is demonstrated by simple product transformations. It allows the convenient construction of α,γ‐substituted chiral γ‐lactams having two carbon stereogenic centres, including one quaternary centre, in a highly enantiomerically pure form. This chemistry may be used to generate analogous molecules of BMS‐561392 for bioactivity screening and drug discovery. [ABSTRACT FROM AUTHOR]

A rhodium-catalyzed enantioselective addition of glyoxylates to arylboronic acids promoted by a simple chiral sulfinamide-based olefin ligand under mild reaction conditions is described. The reaction provides access to a variety of optically active substituted mandelic acid esters in good yields with up to 83% ee. The catalytic system is also applicable to pyruvate addition. The synthetic utility of this method is highlighted by a formal synthesis of the antiplatelet drug clopidogrel. [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]

An efficient rhodium‐catalyzed enantioselective addition of potassium organotrifluoroborates to nitroalkenes powered by simple chiral sulfur‐olefin ligands is reported. This protocol is applicable to a broad range of 2‐aryl‐, alkyl‐, and heteroaryl‐substituted nitroalkenes, allowing access to diverse chiral β,β‐disubstituted nitroethanes in good to excellent yields with high enantioselectivity under mild conditions. [ABSTRACT FROM AUTHOR]

An enantioselective C(sp SP 2 sp )-H functionalization of unprotected indoles, pyrroles, furans, thiophenes, and benzofurans by arylvinylcarbene insertion to generate heteroarene-containing diarylmethine derivatives is reported by Ming-Hua Xu et al. in their Research Article (e202207008). Frontispiece: Rhodium(I) Carbene-Promoted Enantioselective C-H Functionalization of Simple Unprotected Indoles, Pyrroles and Heteroanalogues: New Mechanistic Insights Keywords: Asymmetric Catalysis; C-H Functionalization; Carbene Insertion; Chiral Diene; Unprotected Indoles EN Asymmetric Catalysis C-H Functionalization Carbene Insertion Chiral Diene Unprotected Indoles 1 1 1 08/19/22 20220822 NES 220822 B Asymmetric Catalysis b . [Extracted from the article]