A Convergent Approach to 1,3-Dithiolan-2-ones and an Unexpected Synthesis of Lactones.

A convergent route to 1,3-dithiolan-2-ones based on the radical addition of xanthates to allylic acetates is described. The process is modular, uses inexpensive starting materials and reagents, and is atom economical, since both sulfur atoms of the xanthate end up in the products. With adducts derived from xanthates bearing an ester group, an unexpected transformation leading to lactones was uncovered.

Modular Routes to 1,3-Dithian-2-ones and 1,2-Dithiolanes.

Convergent routes to 1,3-dithian-2-ones based on the radical addition of xanthates to alkenes possessing a suitably located (latent) leaving group are described. These can be converted into 1,2-dithiolanes by base-mediated hydrolysis and oxidation. A broad variety of functional groups can be introduced, and the process is modular, uses inexpensive starting materials and reagents, and is atom economical, because both sulfur atoms of the xanthate end up in the products.

Unusual neurological manifestations of bilateral medial medullary infarction: A case report.

Bilateral medial medullary infarction (BMMI) is an extremely rare type of cerebrovascular accident often resulting in poor functional consequences. "Heart appearance" on diffusion-weighted imaging (DWI) of magnetic resonance imaging (MRI) is the unique presentation of BMMI. In this article, we present an acute ischemic stroke patient whose brain MRI showed the atypical "heart appearance" sign, manifested unusual bilateral central facial paralysis concurrently. For an early diagnosis of BMMI, it is essential to recognize the characteristic clinical and MRI findings of this rare type of stroke. Abnormal small dot or linear DWI signal at the midline of the brainstem should not be ignored at the early stage of stroke.

Transition-Metal-Free One-Step Synthesis of Ynamides.

A robust transition-metal-free one-step strategy for the synthesis of ynamides from sulfonamides and ( Z)-1,2-dichloroalkenes or alkynyl chlorides is presented. This method is not only effective for internal ynamides but also amenable for terminal ynamides. Various functional groups, even the vinyl moiety, are compatible, and thus, this strategy offers the opportunity for further functionalization.

Regio- and Stereo-Selective Intermolecular Hydroamidation of Ynamides: An Approach to ( Z)-Ethene-1,2-Diamides.

An efficient intermolecular trans-selective ß-hydroamidation of ynamides to furnish a series of ( Z)-ethene-1,2-diamide derivatives with excellent regio- and stereo-selectivities is described. The trans-ß-addition reactions have been illustrated for a wide range of substrates and proceeded under basic reaction conditions using readily available materials in the absence of a transition-metal catalyst. The synthetic approach to these novel ( Z)-ethene-1,2-diamide derivatives paves the way for further exploration of their synthetic application.

A Robust One-Step Approach to Ynamides.

A robust one-step synthetic strategy for ynamide with cheap and easily available stock chemicals vinyl dichlorides and electron deficient amides as the starting material is described. In the absence of transition-metal catalyst, the reaction proceeds under mild reaction conditions in open air and thus rendering a convenient operation. This strategy is not only suitable for both terminal and internal ynamide synthesis but also amenable for large-scale preparation. Broad substrate scopes with respect to vinyl dichloride as well as electron-deficient amide were observed.

Inhibition of miR-143 during ischemia cerebral injury protects neurones through recovery of the hexokinase 2-mediated glucose uptake.

Ischemic stroke, a major cause of death, is caused by occlusion of a blood vessel, resulting in significant reduction in regional cerebral blood flow. MiRNAs are a family of short noncoding RNAs (18-22 nts) and bind the 3'-UTR of their target genes to suppress the gene expression post-transcriptionally. In the present study, we report that miR-143 is down-regulated in rat neurones but highly expressed in astrocytes. In vivo middle cerebral artery occlusion (MCAO) and ex vivo oxygen-glucose deprivation (OGD) results showed that miR-143 was significantly induced by ischemia injury. Meanwhile, we observed suppression of glucose uptake and lactate product of rat brain and primary neurones after MCAO or OGD. The glycolysis enzymes hexokinase 2 (HK2), PKM2, and LDHA were inhibited by MCAO or OGD at protein and mRNA levels. In addition, overexpression of miR-143 significantly inhibited HK2 expression, glucose uptake, and lactate product. We report that HK2 is a direct target of miR-143. Importantly, restoration of HK2 in miR-143 overexpressing rat neurones recovered glucose uptake and lactate product. Our results demonstrated inhibition of miR-143 during OGD could protect rat neuronal cells from ischemic brain injury (IBI). In summary, the present study reveals a miRNA-mediated neuron protection during IBI, providing a new strategy for the development of therapeutic agents against IBI.