Overexpression of miR-328-3p Inhibits Epithelial-Mesenchymal Transition in Prostate Cancer by Downregulating PFN1.

MicroRNA (miR)-328-3p is believed to have anti-tumor impacts in various human cancers. However, its role in prostate cancer (PCa) is uncertain. In this research, miR-328-3p expression in PCa was reduced.

Asymmetric S-Arylation of Sulfenamides to Access Axially Chiral Sulfilimines Enabled by Anionic Stereogenic-at-Cobalt(III) Complexes.

An efficient enantioselective coupling reaction between sulfenamides and cyclic diaryliodonium salts is established via adaptive Cu/anionic stereogenic-at-Co(III) complex combined catalysis, precisely synthesizing a broad range of axially chiral sulfilimines with excellent enantioselectivities, diastereoselectivities, regioselectivities, and chemoselectivities (67 examples under same conditions, up to 98 % ee). The following thermodynamically controlled pyramidal inversion enables efficient stereodivegent synthesis of all four stereoisomers. Mechanistic studies suggest that anionic stereogenic-at-cobalt(III) complexes serve as counteranions of diaryliodonium and anionic ligand of Cu(I) catalyst simultaneously, which could be regarded as an explanation for outstanding selectivities.

Base-Promoted Coupling of HFIP in Cu-Catalyzed Asymmetric Ring Opening of Cyclic Diaryliodoniums.

We report a Cu-catalyzed asymmetric ring-opening reaction of cyclic diaryliodoniums with 1,1,1,3,3,3-hexafluoroisopropanol (HFIP), enabling the construction of axially chiral biaryl compounds containing HFIP ether. HFIP is highly polar and exceptionally stable; thus, it is commonly used as a solvent due to its poor nucleophilicity. However, its use as a nucleophilic reagent has been rare.

Coplanar Atropochiral 5H-Cyclopenta[2,1-b:3,4-b']dipyridine Ligands: Synthesis and Applications in Asymmetric Ring-Opening Reaction.

Bipyridines represent a class of ligands renowned for their versatility and efficacy in numerous transition metal-catalyzed reactions. Chiral bipyridine ligands are noted for their distinctive reactivity and stereoselectivity. In this work, we have designed and synthesized a class of bipyridine ligands endowed with an axially chiral scaffold.

Quaternary Chiral Phthalides Enabled by Dirhodium(II)/Phosphine Catalyzed Asymmetric Carbonyl Addition Cascade.

The catalytic asymmetric synthesis of chiral phthalides has garnered considerable interest. However, the construction of phthalides with a chiral quaternary carbon stereocenter still remains challenging. In this study, we developed a new strategy toward catalytic asymmetric synthesis of chiral 3,3-disubstituted phthalides via a dirhodium(II)/phosphine-catalyzed carbonyl addition cascade, yielding phthalides with up to 97% ee values.

Development of a Nomogram That Predicts the Risk of Atrial Fibrillation in Patients with Coronary Heart Disease.

Objective: To explore the risk factors of atrial fibrillation (AF) in patients with coronary heart disease (CHD), and to construct a risk prediction model.

Methods: The participants in this case-control study were from the cardiovascular Department of Changzhou Affiliated Hospital of Nanjing University of Chinese Medicine from June 2016 to June 2023, and they were divided into AF group and non-AF group according to whether AF occurred during hospitalization. The clinical data of the two groups were compared by retrospective analysis.

Symmetric Anion Mediated Dynamic Kinetic Asymmetric Knoevenagel Reaction for N-C and N-N Atropisomers Synthesis.

A symmetric anion mediated dynamic kinetic asymmetric Knoevenagel reaction was established as a general and efficient method for accessing both N-C and N-N atropisomers. The resulting highly enantio-pure pyridine-2,6(1H,3H)-diones exhibit diverse structures and functional groups. The key to excellent regio- and remote enantiocontrol could be owed to the hydrogen bond between the enolate anion and triflamide block of the organocatalyst.

Spatial decoupling of bromide-mediated process boosts propylene oxide electrosynthesis.

The electrochemical synthesis of propylene oxide is far from practical application due to the limited performance (including activity, stability, and selectivity). In this work, we spatially decouple the bromide-mediated process to avoid direct contact between the anode and propylene, where bromine is generated at the anode and then transferred into an independent reactor to react with propylene. This strategy effectively prevents the side reactions and eliminates the interference to stability caused by massive alkene input and vigorously stirred electrolytes.

Kinetic Resolution of Helicenols via Palladium-Catalyzed Atroposelective C-C Bond Cleavage/Ring-Opening Reaction.

Helicenes represent a class of inherently chiral structures that lack conventional chiral elements, such as stereogenic centers, chiral axes, or plane. The asymmetric synthesis of these helical compounds can be particularly challenging as a result of their pronounced molecular strain. In this study, we report a palladium-catalyzed atroposelective carbon-carbon bond cleavage reaction of helical tertiary alcohols.

Regio- and Atroposelective Ring-Opening of 1H-Benzo[4,5]oxazolopyridinones.

The development of new methods for regio- and stereoselective activation of C-O bonds in ethers holds significant promise for synthetic chemistry, offering advantages in terms of environmental sustainability and economic efficiency. Moreover, the C-N atropisomers represent a fascinating and crucial chiral system, extensively found in natural products, pharmaceutical leads, and the frameworks of advanced materials. In this work, we have introduced a nickel-catalyzed regio- and enantioselective carbon-oxygen arylation reaction for atroposelective synthesis of N-arylisoquinoline-1,3(2H,4H)-diones.

Conjugation-Induced Spin Delocalization in Helical Chiral Carbon Radicals via Through-Bond and Through-Space Effects.

A class of highly stable hydrocarbon radicals with helical chirality are synthesized, which can be isolated and purified by routine column chromatography on silica gel. These carbon-centered radicals are stabilized by through-bond delocalization and intramolecular through-space conjugation, which is evidenced by Density Functional Theory (DFT) calculation. The high stability enables to directly modify the carbon radical via palladium-catalyzed cross-coupling with the radical being untapped.

A Chiral Relay Race: Stereoselective Synthesis of Axially Chiral Biaryl Diketones through Ring-Opening of Optical Dihydrophenan-threne-9,10-diols.

We report herein a point-to-axial chirality transfer reaction of optical dihydrophenanthrene-9,10-diols for the synthesis of axially chiral diketones. Two sets of conditions, namely a basic BuOK/air atmosphere and an acidic NaClO/-BuNHSO, were developed to oxidatively cleave the C-C bond, resulting in the formation of axially chiral biaryl diketones. Finally, brief synthetic applications of the obtained chiral aryl diketones were demonstrated.

Stereoselective Synthesis Axially Chiral Arylnitriles through Base-Induced Chirality-Relay β-Carbon Elimination of α-Hydroxyl Ketoxime Esters.

We report herein a point-to-axial chirality transfer reaction of α-hydroxyl oxime esters for the synthesis of axially chiral arylnitriles. The reaction proceeds smoothly through a base-promoted retro-benzoin condensation reaction of α-hydroxyl oxime esters, where the axial chirality is created via the C-C bond cleavage based on a proper distorted conformation of the biaryl structure induced by its stereogenic carbon center.

Confronting the Challenge of Asymmetric Carbonyl Addition to Sterically Bulky Isatins: Upgrading Dirhodium(II)/Biphosphine Catalytic System.

Catalytic asymmetric addition of arylboronic acids to ketones is a powerful transformation for directly delivering chiral tertiary alcohols. However, there is no successful example of enantioselective addition to steric bulky isatins, which contain bulky substituent at the 4-position. To confront this challenge, in this work a dirhodium/(BTFM-Garphos) system was developed that showed extremely high activity and stereoselectivity, and the reactions were usually finished within a few minutes.

Dirhodium(II)/Phosphine Catalyst with Chiral Environment at Bridging Site and Its Application in Enantioselective Atropisomer Synthesis.

A dirhodium(II)/phosphine catalyst with a chiral environment at the bridging site was developed for the asymmetric arylation of phenanthrene-9,10-diones with arylboronic acids. In contrast to the classic chiral bridging carboxylic acid (or derivatives) ligand strategy of bimetallic dirhodium(II) catalysis, in this reaction, tuning both axial and bridging ligands realized the first Rh(OAc)/phosphine-catalyzed highly enantioselective carbonyl addition reaction. The kinetic analysis reveals that dirhodium(II) and arylboronic acid follow the first-order kinetics, while phenanthrene-9,10-dione is zeroth-order.

Atroposelective Three-Component Coupling of Cyclic Diaryliodoniums and Sodium Cyanate Enabled by the Dual-Role of Phenol.

A copper-catalyzed atroposelective ring-opening reaction of cyclic diaryliodoniums, sodium cyanate (NaOCN) and phenols is reported. The reaction chemoselectively affords axially chiral carbamates by sequential coupling of cyclic diaryliodonium and NaOCN, followed by phenol. Mechanistic investigations revealed that phenol is not only a reagent to trap highly active intermediate isocyanates, but it also activates the copper catalyst as a standby ligand.

Divergent Synthesis of Helical Ketone Enabled by Rearrangement of Spiro Carbocation.

An acid-mediated electrophilic cyclization of 2-alkynyl-1,1'-biphenyls for the divergent synthesis of angular, bent, and zigzag fused nonplanar conjugated organic molecules was realized. The key feature of this reaction is a Wagner-Meerwein-type rearrangement via a spiro carbocation intermediate, which was formed by electrophilic cyclization of the 9-fluoren-9-one derivative at the position. The products can be advanced to helical fluorenes, which exhibit high fluorescence quantum yields.

Recent Progress in Cyclic Aryliodonium Chemistry: Syntheses and Applications.

Hypervalent aryliodoumiums are intensively investigated as arylating agents. They are excellent surrogates to aryl halides, and moreover they exhibit better reactivity, which allows the corresponding arylation reactions to be performed under mild conditions. In the past decades, acyclic aryliodoniums are widely explored as arylation agents.

Gold Nanoclusters Enhance the Efficacy of the Polymer-Based Chaperone in Restoring and Maintaining the Native Conformation of Human Islet Amyloid Polypeptide.

The misfolding and un-natural fibrillation of proteins/peptides are associated with many conformation diseases, such as human islet amyloid polypeptide (hIAPP) in type 2 diabetes (T2D). Inspired by molecular chaperones maintaining protein homeostasis , many polymer-based artificial chaperones were introduced to regulate protein/peptide folding and fibrillation. However, the pure polymer chaperones prefer to agglomerate into large-size micelles in the physiological environment and thus lose their chaperone functions, which greatly restricts the application of polymer-based chaperones.

Synthesis of Atropisomers with Biaryl and Vinylaryl Chirality via Pd-Catalyzed Point-to-Axial Chirality Transfer Ring-Opening Reaction.

A palladium-catalyzed domino cyclization/ring-opening reaction between 8-indeno[1,2-]thiophen-8-ols and -(2-bromophenyl)propiolamide derivatives is reported. The reaction features a highly stereospecific point chirality to axial chirality transfer process, which enables the synthesis of molecules containing two chiral axes from the compounds with only one stereogenic center.

Nitrenoid from Oxime: A Practical Synthesis of Planar Chiral Ferrocenyl Phenanthridines via Nitrene-Involved Ring-Expansion Reaction.

Nitrenes and nitrenoids are highly reactive species and the proposed key intermediates in nitrogen-containing heterocyclic compound synthesis. In this work, we developed a practical method for the synthesis of phenanthridines by the reaction of oximes and Grignard reagents (with or without diethylzinc) via ring-expansion of magnesium coordinated nitrenoid complex as the key step. The method has been used to synthesize optically active planar chiral ferrocenyl phenanthridines.

Synthesis of 2-Aryl Azetidines through Pd-Catalyzed Migration/Coupling of 3-Iodoazetidines and Aryl Boronic Acids.

A palladium-catalyzed cross-coupling of 3-iodoazetidines and nonheteroaryl boronic acids was reported. The [1,1'-biphenyl]-2-yldicyclohexylphosphane ligand enabled the reaction that favored the formation of 2-aryl azetidines. The control experiments indicated that the reaction can proceed through either a palladium-hydride/dihydroazete complex or free dihydroazete intermediate followed by hydropalladation.

Transition Metal-Catalyzed Biaryl Atropisomer Synthesis via a Torsional Strain Promoted Ring-Opening Reaction.

Arising from the restricted rotation of a single bond caused by steric or electronic effects, atropisomerism is one of the few fundamental categories for molecules to manifest their three-dimensional characters into which axially chiral biaryl compounds fall. Despite the widespread occurrence of axially chiral skeletons in natural products, bioactive molecules, and chiral ligands/organocatalysts, catalytic asymmetric methods for the synthesis of these structures still lag behind demand. Major challenges for the preparation of these chiral biaryls include accessing highly sterically hindered variants while controlling the stereoselectivity.