Selective difunctionalization of electron-deficient alkynes: access to (E)-2-iodo-3-(methylthio)acrylate.

A convenient and efficient approach to (E)-2-iodo-3-(methylthio)acrylate has been developed through direct iodothiomethylation of alkynes with aqueous HI and DMSO under mild conditions. This novel protocol has demonstrated a unique difunctionalization of electron-deficient alkynes with a broad substrate scope and excellent functional-group tolerance. Preliminary mechanistic studies indicated that prior diiodination of alkynes, followed by nucleophilic substitution with in situ generated DMS led to the formation of (E)-2-iodo-3-(methylthio)acrylate.

Metal-free difunctionalization of alkynes leading to alkenyl dithiocyanates and alkenyl diselenocyanates at room temperature.

A simple and practical method for the synthesis of alkenyl dithiocyanates and alkenyl diselenocyanates has been developed via stereoselective difunctionalization of alkynes with NaSCN or KSeCN at room temperature. Through this methodology, a series of alkenyl dithiocyanates and alkenyl diselenocyanates could be efficiently and conveniently obtained in moderate to good yields under mild and metal-free conditions by the simple use of oxone and PhI(OAc)2 as the oxidants.

Recent advances of 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) in photocatalytic transformations.

1,2,3,5-Tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) is a typical donor-acceptor fluorophore, with carbazolyl as an electron donor and dicyanobenzene as an electron acceptor. It has emerged as a powerful organophotocatalyst since 2016. Excellent redox window, good chemical stability and broad applicability make 4CzIPN an attractive metal-free photocatalyst. In this review, the recent advances of the application of 4CzIPN as a photoredox catalyst in the past three years (2016-2018) for various organic reactions are summarized.

Cardioprotective effects of Qishen Granule () on sarcoplasmic reticulum Ca2+ handling in heart failure rats.

OBJECTIVE: To assess the effects of Qishen Granule (, QSG) on sarcoplasmic reticulum (SR) Ca2+ handling in heart failure (HF) model of rats and to explore the underlying molecular mechanisms. METHODS: HF rat models were induced by left anterior descending coronary artery ligation surgery and high-fat diet feeding. Rats were randomly divided into sham (n=10), model (n=10), QSG (n=12, 2.2 g/kg daily) and metoprolol groups (n=12, 10.5 mg/kg daily). The therapeutic effects of QSG were evaluated by echocardiography and blood lipid testing. Intracellular Ca2+ concentration and sarco-endoplasmic reticulum ATPase 2a (SERCA2a) activity were detected by specifific assay kits. Expressions of the critical regulators in SR Ca2+ handling were evaluated by Western blot and real-time quantitative polymerase chain reaction. RESULTS: HF model of rats developed ventricular remodeling accompanied with calcium overload and defective Ca2+ release-uptake cycling in cardiomyocytes. Treatment with QSG improved contractive function, attenuated ventricular remodeling and reduced the basal intracellular Ca2+ level. QSG prevented defective Ca2+ leak by attenuating hyperphosphorylation of ryanodine receptor 2, inhibiting expression of protein kinase A and up-regulating transcriptional expression of protein phosphatase 1. QSG also restored Ca2+ uptake by up-regulating expression and activity of SERCA2a and promoting phosphorylation of phospholamban. CONCLUSION: QSG restored SR Ca2+ cycling in HF rats and served as an ideal alternative drug for treating HF.

Metabolomic profiling reveals distinct patterns of tricarboxylic acid disorders in blood stasis syndrome associated with coronary heart disease.

OBJECTIVE: To investigate the underlying metabolomic profifiling of coronary heart disease (CHD) with blood stasis syndrome (BSS). METHODS: CHD model was induced by a nameroid constrictor in Chinese miniature swine. Fifteen miniature swine were randomly divided into a model group (n=9) and a control group (n=6), respectively according to arandom number table. After 4 weeks, plasma hemorheology was detected by automatic hemorheological analyzer, indices including hematocrit, plasma viscosity, blood viscosity, rigidity index and erythrocyte sedimentation rate; cardiac function was assessed by echocardiograph to detect left ventricular end-systolic diameter (LVED), left ventricular end-diastolic diameter (LVEDd), ejection fraction (EF), fractional shortening (FS) and other indicators. Gas chromatography coupled with mass spectrometry (GC-MS) and bioinformatics were applied to analyze spectra of CHD plasma with BSS. RESULTS: The results of hemorheology analysis showed signifificant changes in viscosity, with low shear whole blood viscosity being lower and plasma viscosity higher in the model group compared with the control group. Moreover, whole blood reduction viscosity at high shear rate and whole blood reduction viscosity at low shear rate increased signifificantly (P <0.05). The echocardiograph results demonstrated that cardiac EF and FS showed signifificant difference (P <0.05), with EF values being decreased to 50% or less. The GC-MS data showed that principal component analysis can clearly separate the animals with BSS from those in the control group. The enriched Kyoto Encyclopedia of Genes and Genomes biological pathways results suggested that the patterns involved were associated with dysfunction of energy metabolism including glucose and lipid disorders, especially in glycolysis/gluconeogenesis, galactose metabolism and adenosine-triphosphate-binding cassette transporters. CONCLUSIONS: Glucose metabolism and lipid metabolism disorders were the major contributors to the syndrome classifification of CHD with BSS.