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Medium-ring lactones are synthetically challenging due to unfavorable energetics involved in cyclization. We have discovered a thioesterase enzyme DcsB, from the decarestrictine C1 (1) biosynthetic pathway, that efficiently performs medium-ring lactonizations. DcsB shows broad substrate promiscuity toward linear substrates that vary in lengths and substituents, and is a potential biocatalyst for lactonization. X-ray crystal structure and computational analyses provide insights into the molecular basis of catalysis.

The selective functionalization of 1,3-bis(boronic) esters holds the potential for creating diverse molecular structures, particularly through the late-stage functionalization of the remaining C–B bond. By employing distinct organometallic reagents, we have developed a method for regiodivergent alkynylation of 1,3-bis(boronic) esters, facilitated by unique chelation patterns. Notably, this methodology effectively overcomes limitations commonly encountered in radical chemistry, which generates only monoselective downstream targets. Furthermore, the compounds synthesized through this approach can serve as significant building blocks, contributing to the construction of molecular complexity. [ABSTRACT FROM AUTHOR]

The construction of acyclic, non‐adjacent 1,3‐stereogenic centers, prevalent motifs in drugs and bioactive molecules, has been a long‐standing synthetic challenge due to acyclic nucleophiles being distant from the chiral environment. In this study, we successfully synthesized highly valuable 1,2‐bis(boronic) esters featuring acyclic and nonadjacent 1,3‐stereocenters. Notably, this reaction selectively produces migratory coupling products rather than alternative deborylative allylation or direct allylation byproducts. This approach introduces a new activation mode for selective transformations of gem‐diborylmethane in asymmetric catalysis. Additionally, we found that other gem‐diborylalkanes, previously challenging due to steric hindrance, also successfully participated in this reaction. The incorporation of 1,2‐bis(boryl)alkenes facilitated the diversification of the alkenyl and two boron moieties in our target compounds, thereby enabling access to a broad array of versatile molecules. DFT calculations were performed to elucidate the reaction mechanism and shed light on the factors responsible for the observed excellent enantioselectivity and diastereoselectivity. These were determined to arise from ligand‐substrate steric repulsions in the syn‐addition transition state. [ABSTRACT FROM AUTHOR]

Asymmetric cross‐couplings based on 1,2‐carbon migration from B‐ate complexes have been developed efficiently to access valuable organoboronates. However, enantioselective reactions triggered by 1,2‐boron shift have remained to be unaddressed synthetic challenge. Here, Ir‐catalyzed asymmetric allylic alkylation enabled by 1,2‐boron shift was developed. In this reaction, we disclosed that excellent enantioselectivities were achieved through an interesting dynamic kinetic resolution (DKR) process of allylic carbonates at the elevated temperature. Notably, the highly valuable (bis‐boryl)alkenes have enabled an array of diversifications to access versatile molecules. Extensive experimental and computational studies were conducted to elucidate the reaction mechanism of DKR process and clarify the origin of excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Key Scientists Organoborons are commonly used building blocks for rapidly increasing molecular complexity. Although significant progress has been made in the selective functionalization of mono‐organoborons, the site‐selective functionalization of poly(organoborons) has attracted substantial interest in organic synthesis, pharmaceuticals, and agrochemicals due to the presence of multiple potential reaction sites. This review discusses various activation modes of the target C–B bond, with diverse transformations being achieved in both a selective and efficient manner. Recent advances in the catalytic selective transformations of 1,n‐diboronates through ionic and radical pathways are highlighted. Furthermore, we summarize the existing challenges and future research directions in this field.In 1993, Suzuki, Miyaura and coworkers developed a pioneering example of selective arylation towards cis‐1,2‐bis(boryl) alkenes, marking the inception of this field. The Morken group has made significant contributions to the asymmetric diboration of alkenes and realized elegant catalytic functionalization of these compounds since 2004. In 2016, Fernández and colleagues achieved the selective arylation of the internal C–B bond of tri(boronates). Since 2019, the Aggarwal group has developed efficient Giese‐type addition and selective arylation at the more substituted C–B bond of 1,2‐bis(boronic) esters through photoredox catalysis. The controllable regiodivergent alkynylation of 1,3‐bis(boronic) esters was developed by Gao and coworkers in 2023. Recently, Qin conducted elegant research on the programmable late‐stage functionalization of bridge‐substituted bicyclo[1.1.1]pentane (BCP) bis‐boronates. Since 2013, catalytic stereoselective transformations have been developed by several groups, including those led by Morken and Chen. This review summarizes the latest and most significant developments in this field since 1993. [ABSTRACT FROM AUTHOR]

A palladium(II)-catalyzed enantioselective α-alkylation of azlactones with nonconjugated alkenes is described. The reaction employs a chiral BINOL-derived phosphoric acid as the source of stereoinduction, and a cleavable bidentate directing group appended to the alkene to control the regioselectivity and stabilize the nucleopalladated alkylpalladium(II) intermediate in the catalytic cycle. A wide range of azlactones were found to be compatible under the optimal reaction conditions to afford products bearing α,α-disubstituted α-amino-acid derivatives with high yields and high enantioselectivity., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Removable tridentate directing groups inspired by pincer ligands have been designed to stabilize otherwise kinetically and thermodynamically disfavored 6-membered alkyl palladacycle intermediates. This family of directing groups enables regioselective remote hydrocarbofunctionalization of several synthetically useful alkene-containing substrate classes, including 4-pentenoic acids, allylic alcohols, homoallyl amines, and bis-homoallylamines, under Pd(II) catalysis. In conjunction with previous findings, we demonstrate regiodivergent hydrofunctionalization of 3-butenoic acid derivatives to afford either Markovnikov or anti-Markovnikov addition products depending on directing group choice. Preliminary mechanistic and computational data are presented to support the proposed catalytic cycle.

Objectives: To investigate clinical characteristics, target organ damage, and the associated risk factors of the patients aged ≥ 80 years with true resistant hypertension (RH)., Methods: Patients aged ≥ 80 years with hypertension ( n = 1163) were included in this study. The included participants attended a structured clinical examination and an evaluation of RH was carried out. The prevalence, clinical characteristics and target organ damage of patients with RH were assessed. The associated clinical risk factors were analyzed by using logistic regression., Results: The prevalence of RH diagnosis by 24-h ambulatory blood pressure monitoring assessment was 21.15%. End-diastolic left ventricular internal dimension, left ventricular mass index as well as prevalence of left ventricular hypertrophy were significantly greater in patients with RH than in control group. The common carotid artery intimal media thickness, carotid walls thickness, common carotid artery diameter and relative wall thickness were significant greater in RH group than in control. A relatively higher level of creatinine, estimated glomerular filtration rate, microalbuminuria and retinal changes was found in RH group than in control. A multivariate analysis showed that patients with a history of diabetes, higher body mass index (BMI) and lipid profiles were independent risk factors of RH., Conclusions: The prevalence of RH in patients aged ≥ 80 years was within the range of reported rates of the general population. Subjects with RH diagnosis showed a higher occurrence of target organ damage than patients with well controlled blood pressure. Patients with diabetes, higher BMI and serum lipid profiles were independent risk factors for RH in patients aged ≥ 80 years.

Enantioselective Pd(II)-catalyzed direct coupling of aminomethylferrocene derivatives with boronic acids was realized. With commercially available Boc-L-Val-OH as a ligand, planar-chiral ferrocenes could be synthesized in yields of 14-81% with up to 99% ee under mild conditions.

Objective: To study the expression changes of neuroglobin in rats with the model of diffuse traumatic brain injury and explore the relationship between the neuroglobin and neuron apoptosis in traumatic brain injury., Methods: The diffuse traumatic brain injury of rats was induced by the Marmarou's 'weight-drop' device. And the immunohistochemical technique was used to detect the expression changes of neuroglobin and neuron apoptosis in rat brain at different time points post-injury., Results: The expression of neuroglobin increased twice and reached peaks at 2 hours and 72 hours post-injury respectively. And the increased expression of neuroglobin from 30 minutes to 1 hour post-injury and from 48 hours to 72 hours post-injury accompanied with the decreased expression ratio of Bax to Bcl-2., Conclusion: The increased expression of neuroglobin in traumatic brain injury informed us that neuroglobin had anti-apoptosis action in post-injury neuron. It could protect the neuron from traumatic stress and secondary ischemia and hypoxia insults during ultra-early and acute stages.