Rh-Catalyzed Carbonylative Cyclization of Propargylic Alcohols with Aryl Boronic Acids.

2(3)-Furanones are tremendously important not only because of their wide occurrence in bioactive compounds but also due to their versatility in organic synthesis. Here, a straightforward approach to 2(3)-furanones from readily available tertiary propargylic alcohols with arylboronic acids in the presence of CO using rhodium as a catalyst has been established. The method exhibits a broad substrate scope tolerating useful functional groups with a moderate to high stereoselectivity.

Modular and diverse synthesis of amino acids via asymmetric decarboxylative protonation of aminomalonic acids.

Stereoselective protonation is a challenge in asymmetric catalysis. The small size and high rate of transfer of protons mean that face-selective delivery to planar intermediates is hard to control, but it can unlock previously obscure asymmetric transformations. Particularly, when coupled with a preceding decarboxylation, enantioselective protonation can convert the abundant acid feedstocks into structurally diverse chiral molecules.

Stereoselectivity control in Rh-catalyzed β-OH elimination for chiral allene formation.

Stereoselectivity control and understanding in the metal-catalyzed reactions are fundamental issues in catalysis. Here we report sterically controlled rhodium-catalyzed S2'-type substitution reactions of optically active tertiary propargylic alcohols with arylmetallic species affording the non-readily available enantioenriched tetrasubstituted allenes via either exclusive syn- or anti-β-OH elimination, respectively, under two sets of different reaction parameters. Detailed mechanistic experiments and density functional theory (DFT) studies reveal that the exclusive anti-Rh(I)-OH elimination is dictated by the simultaneous aid of in situ generated boric acid and ambient water, which act as the shuttle in the hydroxy relay to facilitate the Rh(I)-OH elimination process via a unique ten-membered cyclic transition state (anti-TS2_u).

Ti-Catalyzed Diastereoselective Cyclopropanation of Carboxylic Derivatives with Terminal Olefins.

Cyclopropanols and cyclopropylamines not only serve as important structural motifs in medicinal chemistry but also show diverse reactivities in organic synthesis. Owing to the high ring strain energy, the development of a general protocol from stable and readily available starting materials to afford these cyclopropyl derivatives remains a compelling challenge. Herein, we describe that a Ti-based catalyst can effectively promote the diastereoselective syntheses of cyclopropanols and cyclopropylamines from widely accessible carboxylic derivatives (acids, esters, amides) with terminal olefins.

Chirality memory of α-methylene-π-allyl iridium species.

Chirality is one of the most important types of steric information in nature. In addition to central chirality, axial chirality has been catching more and more attention from scientists. However, although much attention has recently been paid to the creation of axial chirality and the chirality transfer of allenes, no study has been disclosed as to the memory of such an axial chirality.

A palladium-catalyzed approach to allenic aromatic ethers and first total synthesis of terricollene A.

A palladium-catalyzed C-O bond formation reaction between phenols and allenylic carbonates to give 2,3-allenic aromatic ethers with decent to excellent yields under mild reaction conditions has been described. A variety of synthetically useful functional groups are tolerated and the synthetic utility of this method has been demonstrated through a series of transformations of the allene moiety. By applying this reaction as the key step, the total syntheses of naturally occurring allenic aromatic ethers, eucalyptene and terricollene A (first synthesis; 4.

Pd-Catalyzed Enantioselective Syntheses of Trisubstituted Allenes via Coupling of Propargylic Benzoates with Organoboronic Acids.

Enabled by the newly developed ligand, Ming-Phos, the first example of palladium-catalyzed highly enantioselective coupling of racemic propargylic benzoates with organoboronic acids for chiral allenes synthesis has been developed. Excellent asymmetric induction has been achieved with a decent substrate scope. Synthetic potentials for the construction of polycyclic compounds with multiple chiral centers have been demonstrated.

C1qTNF-related protein-6 protects against doxorubicin-induced cardiac injury.

The clinical use of doxorubicin (DOX) is limited by its toxic effect. However, there is no specific drug that can prevent DOX-related cardiac injury. C1qTNF-related protein-6 (CTRP6) is a newly identified adiponectin paralog with many protective functions on metabolism and cardiovascular diseases.

Combined value of red blood cell distribution width and global registry of acute coronary events risk score on predicting long-term major adverse cardiac events in STEMI patients undergoing primary PCI.

The combined value of RDW and GRACE risk score for cardiovascular prognosis in ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) has not been fully investigated. This study was designed to explore the combined value of RDW and GRACE risk score on predicting long-term major adverse cardiac event (Mace) in STEMI patients undergoing primary PCI. This study included 390 STEMI patients.

Rhodium-Catalyzed Regio- and Stereoselective [2 + 2] Cycloaddition of Allenamides.

A highly regio- and stereoselective Rh-catalyzed intermolecular head-to-head [2 + 2] cycloaddition of allenamides was developed. The intermolecular cycloadducts, trans-dimethylenecyclobutane-1,2-diamine derivatives, were achieved in good yields with high regioselectivity and stereoselectivity.

Correlation between plasma lipoprotein-associated phospholipase A and peripheral arterial disease.

Lipoprotein-associated phospholipase A (Lp-PLA) is a recently identified and potentially useful plasma biomarker for cardiovascular diseases. However, its role in peripheral arterial disease (PAD) remains unclear. The objective of this study was to assess the independent association of Lp-PLA and other inflammatory markers with the reduced ankle-brachial blood pressure index (ABI), a marker of PAD.

Myeloperoxidase and risk of recurrence of atrial fibrillation after catheter ablation.

Background: Myeloperoxidase (MPO) has been associated with the development of atrial fibrillation (AF), but its impact on the recurrence of AF after catheter ablation has not been explored. This study investigated the effect of plasma MPO on recurrence after catheter ablation of paroxysmal AF.

Methods And Results: Two hundred eighty-eight consecutive patients with paroxysmal AF and who underwent circumferential pulmonary vein isolation were prospectively enrolled.