Superelectrophilic Activation of Phosphacoumarins towards Weak Nucleophiles via Brønsted Acid Assisted Brønsted Acid Catalysis.

The electrophilic activation of various substrates via double or even triple protonation in superacidic media enables reactions with extremely weak nucleophiles. Despite the significant progress in this area, the utility of organophosphorus compounds as superelectrophiles still remains limited. Additionally, the most common superacids require a special care due to their high toxicity, exceptional corrosiveness and moisture sensitivity. Herein, we report the first successful application of the "Brønsted acid assisted Brønsted acid" concept for the superelectrophilic activation of 2-hydroxybenzo[e][1,2]oxaphosphinine 2-oxides (phosphacoumarins). The pivotal role is attributed to the tendency of the phosphoryl moiety to form hydrogen-bonded complexes, which enables the formation of dicationic species and increases the electrophilicity of the phosphacoumarin. This unmasks the reactivity of phosphacoumarins towards non-activated aromatics, while requiring only relatively non-benign trifluoroacetic acid as the reaction medium.

Hypervalent Sulfur Derivatives as Sulfenylating Reagents: Visible-Light-Mediated Direct Thiolation of Activated C(sp2)-H Bonds with Dihalosulfuranes.

In contrast to hypervalent iodine compounds, the chemistry of their sulfur analogues has been considerably less explored. Herein, we report the direct C-H bond thiolation of electron-rich heterocycles, arenes, and 1,3-dicarbonyls by dichlorosulfuranes under mild conditions. Mechanistic studies and density functional theory calculations suggest the radical chain mechanism of the disclosed transformation. The key to success is attributed to a strikingly low S-Cl bond dissociation energy, which enables the generation of radical species upon exposure to daylight.

One-Step Synthesis of Functionalized Pyrazolo[3,4-b]pyridines via Ring Opening of the Pyrrolinium Ion.

Herein, we report a highly regioselective one-pot synthesis of pyrazolo[3,4-b]pyridines via the reaction of 3-arylidene-1-pyrrolines with aminopyrazoles. The reaction proceeds through the sequential nucleophilic addition/electrophilic substitution/C-N bond cleavage and provides easy access to pyrazolo[3,4-b]pyridine derivatives featuring a primary amino group. Moreover, the reaction can be terminated at the electrophilic substitution stage, thus providing convenient entry to the hardly accessible pyrazolopyrrolopyridine scaffold.

Subclinical Carotid Atherosclerosis in Patients with Rheumatoid Arthritis at Low Cardiovascular Risk.

OBJECTIVE: To evaluate the rate of subclinical carotid atherosclerosis and clinical significance of immunoinflammatory markers in patients with rheumatoid arthritis (RA) at low cardiovascular risk. MATERIALS AND METHODS: The study included 275 RA patients and a control group of 100 participants without autoimmune diseases. All study participants were at low cardiovascular risk, calculated by the QRISK3 scale (<20%), and free of cardiovascular disease. Ultrasound examination of carotid arteries was performed to measure cIMT and to detect atherosclerotic plaques (ASP) in carotid arteries. sIСАМ-1, sVСАМ, and sCD40L levels were determined by enzyme immunoassay. RESULTS: Carotid ASP was observed more frequently in RA patients (27%) than in the control group (17%), p = 0.03. The frequency of ASP in RA patients did not depend on the disease's stage or activity. There was a significant correlation between cIMT and age, cardiovascular risk determined by QRISK3, level of total cholesterol, LDL, and blood pressure in RA patients, p < 0.05 in all cases. No correlation between cIMT and blood levels of sCD40L, sVCAM, and sICAM was found. In RA patients, a higher concentration of sVCAM was detected in the carotid ASP group compared to the non-atherosclerotic group. sCD40L was associated with cIMT and total cholesterol in the ASP group and with total cholesterol and blood pressure in non-atherosclerotic patients. CONCLUSIONS: Subclinical atherosclerotic lesions of the carotid arteries were observed significantly more frequently in RA patients with low cardiovascular risk than in the control group. The results of the study demonstrate the association between cIMT, traditional cardiovascular risk factors, and immunoinflammatory markers in RA patients.

Systemic Sclerosis and Atherosclerosis: Potential Cellular Biomarkers and Mechanisms.

Systemic sclerosis (SSc) is a rare systemic autoimmune disease of unknown etiology, which is characterized by endothelial dysfunction, pathologic vasculopathy, and increased tissue fibrosis. Traditionally, SSc has been regarded as a prototypical fibrotic disease in the family of systemic autoimmune diseases. Traditionally, emphasis has been placed on the three components of the pathogenesis of SSc: vascular, immune, and mesenchymal. Microvascular lesions, including endothelial dysfunction and smooth muscle cell migration into the intima of vessels in SSc, resemble the atherosclerotic process. Although microvascular disease is a hallmark of SSc, understanding the role of atherosclerotic vascular lesions in patients with SSc remains limited. It is still unknown whether the increased cardiovascular risk in SSc is related to specific cardiac complications (such as myocardial fibrosis) or the accelerated development of atherosclerosis. Different immune cell types appear to be involved in the immunopathogenesis of SSc via the activation of other immune cells, fibrosis, or vascular damage. Macrophages, B cells, T cells, dendritic cells, neutrophils, and endothelial cells have been reported to play the most important role in the pathogenesis of SSc and atherosclerosis. In our article, we reviewed the most significant and recent studies on the pathogenetic links between the development of SSc and the atherosclerotic process.

Activation Markers on B and T Cells and Immune Checkpoints in Autoimmune Rheumatic Diseases.

In addition to identifying the major B- and T-cell subpopulations involved in autoimmune rheumatic diseases (ARDs), in recent years special attention has been paid to studying the expression of their activation markers and immune checkpoints (ICPs). The activation markers on B and T cells are a consequence of the immune response, and these molecules are considered as sensitive specific markers of ARD activity and as promising targets for immunotherapy. ICPs regulate the activation of the immune response by preventing the initiation of autoimmune processes, and they modulate it by reducing immune cell-induced organ and tissue damage. The article considers the possible correlation of ICPs with the activity of ARDs, the efficacy of specific ARD treatments, and the prospects for the use of activation molecules and activation/blocking ICPs for the treatment of ARDs.

The Self-Determination Inventory: Student Report American Sign Language Translation.

Research literature and community narratives both emphasize the importance of self-determination in the lives of deaf youth. This paper describes the development, initial validation, and potential applications of a translated measure of self-determination for deaf youth, the SDI:SR ASL Translation (SDI:SR ASL). A sample of 3,309 young people who completed the SDI:SR, of whom 392 were deaf, was used in this validation study. Results provide preliminary support for the use of SDI:SR ASL with deaf youth. Findings also indicate that deaf youth who take the SDI:SR ASL score more similarly to youth without disabilities taking the SDI:SR than youth with disabilities. The SDI:SR ASL can be an important tool for researchers and practitioners to better understand self-determination among deaf youth and facilitate continued development of self-determination skills.

Macrophage Dysfunction in Autoimmune Rheumatic Diseases and Atherosclerosis.

One of the problems of modern medical science is cardiovascular pathology caused by atherosclerotic vascular lesions in patients with autoimmune rheumatic diseases (ARDs). The similarity between the mechanisms of the immunopathogenesis of ARD and chronic low-grade inflammation in atherosclerosis draws attention. According to modern concepts, chronic inflammation associated with uncontrolled activation of both innate and acquired immunity plays a fundamental role in all stages of ARDs and atherosclerotic processes. Macrophage monocytes play an important role among the numerous immune cells and mediators involved in the immunopathogenesis of both ARDs and atherosclerosis. An imbalance between M1-like and M2-like macrophages is considered one of the causes of ARDs. The study of a key pathogenetic factor in the development of autoimmune and atherosclerotic inflammation-activated monocyte/macrophages will deepen the knowledge of chronic inflammation pathogenesis.

From classical to supramolecular dynamic stereochemistry: Double crystallization-induced diastereomerization of thiazine sulfonamide.

The interrelation between the configurational lability of nitrogen and sulfur atoms within the -NH-SO2 group of some thiazine sulfonamides is discussed. We have found that the compounds of the above series can crystallize as various diastereomers by the nitrogen atom, the relative configuration of the nitrogen atom determining the relative supramolecular configuration of the newly formed chiral sulfur atom. The paper presents a stereochemical transformation, which we have called "double crystallization-induced diastereomerization."