1,3-Dipolar Cycloaddition of Nitrile Oxides and Nitrilimines to (-)-β-Caryophyllene: Stereoselective Synthesis of Polycyclic Derivatives and Their Biological Testing.

The cycloaddition of nitrile oxides and nitrilimines to one or both of the C=C double bonds of caryophyllene is described. The possibility of introducing five-membered fused and spiro-linked heterocycles into the structure of sesquiterpenes by the 1,3-dipolar cycloaddition reactions of nitrile oxides and nitrilimines to caryophyllene was demonstrated. As a result of these reactions, pharmacophore fragments of isoxazoline and pyrazoline are introduced into the structure of caryophyllene, which leads to an increase in the conformational rigidity of the molecule.

Fluorinated 2-arylchroman-4-ones and their derivatives: synthesis, structure and antiviral activity.

A number of new biologically interesting fluorinated 2-arylchroman-4-ones and their 3-arylidene derivatives were synthesized based on the p-toluenesulfonic acid-catalyzed one-pot reaction of 2-hydroxyacetophenones with benzaldehydes. It was found that obtained (E)-3-arylidene-2-aryl-chroman-4-ones reacted with malononitrile under base conditions to form 4,5-diaryl-4H,5H-pyrano[3,2-c]chromenes. The structures of the synthesized fluorinated compounds were confirmed by H, F, and C NMR spectral data, and for some representatives of heterocycles also using NOESY spectra and X-ray diffraction analysis.

Novel 1,2,4-Triazole- and Tetrazole-Containing 4-Thiopyrano[2,3-]quinolines: Synthesis Based on the Thio-Michael/aza-Morita-Baylis-Hillman Tandem Reaction and Investigation of Antiviral Activity.

A novel method for synthesizing 1,2,4-triazole- and tetrazole-containing 4-thiopyrano[2,3-]quinolines using a new combination of the thio-Michael and aza-Morita-Baylis-Hillman reactions was developed. Target compounds were evaluated for their cytotoxicities and antiviral activities against influenza A/Puerto Rico/8/34 virus in MDCK cells. The compounds showed low toxicity and some exhibited moderate antiviral activity.

Hemolytic Activity, Cytotoxicity, and Antimicrobial Effects of Silver Nanoparticles Conjugated with Lincomycin or Cefazolin.

The overuse of antibiotics has led to the emergence of resistant bacteria. A good alternative is silver nanoparticles, which have antibacterial activity against Gram-negative and Gram-positive bacteria, including multidrug-resistant strains. Their combination with already known antibiotics has a synergistic effect.

HLA Genotypes in Patients with Infection Caused by Different Strains of SARS-CoV-2.

The aggressive infectious nature of SARS-CoV-2, its rapid spread, and the emergence of mutations necessitate investigation of factors contributing to differences in SARS-CoV-2 susceptibility and severity. The role of genetic variations in the human HLA continues to be studied in various populations in terms of both its effect on morbidity and clinical manifestation of illness. The study included 484 COVID-19 convalescents (northwest Russia residents of St.

[Genetic diversity of the human immunodeficiency virus (HIV-1) in the Kaliningrad region].

Introduction: As is currently known, the epidemic process in the Kaliningrad Region was mainly associated with the spread of the recombinant form of HIV-1 (CRF03_AB); however, regular HIV importations from other countries and continents has created favorable conditions for emergence and spread of various recombinant forms of the virus.The most complete information on the diversity of recombinant forms in the region is also necessary to understand the structure of drug resistance (DR). The aim of the study was to explore the HIV-1 genetic diversity in the Kaliningrad Region.

Colonization by Various Morphological Forms of in the Gingival Sulcus and Antrum of the Stomach.

Background: Helicobacter pylori eradication therapy can be considered effective if the result of its implementation is removed including all roots and rootlets from which surviving H. pylori can repopulate in the gastric mucosa. One of the reasons for the ineffectiveness of eradication therapy can be the continuous presence of viable coccoid forms of H.

Synthesis and Biological Activity of Unsymmetrical Monoterpenylhetaryl Disulfides.

New unsymmetrical monoterpenylhetaryl disulfides based on heterocyclic disulfides and monoterpene thiols were synthesized for the first time in 48-88% yields. Hydrolysis of disulfides with fragments of methyl esters of 2-mercaptonicotinic acid was carried out in 73-95% yields. The obtained compounds were evaluated for antioxidant, antibacterial, antifungal activity, cytotoxicity and mutagenicity.

Synthesis of Pyrimidine Conjugates with 4-(6-Amino-hexanoyl)-7,8-difluoro-3,4-dihydro-3-methyl-2-[1,4]benzoxazine and Evaluation of Their Antiviral Activity.

A series of pyrimidine conjugates containing a fragment of racemic 7,8-difluoro-3,4-dihydro-3-methyl-2-[1,4]benzoxazine and its ()-enantiomer attached via a 6-aminohexanoyl fragment were synthesized by the reaction of nucleophilic substitution of chlorine in various chloropyrimidines. The structures of the synthesized compounds were confirmed by H, F, and C NMR spectral data. Enantiomeric purity of optically active derivatives was confirmed by chiral HPLC.

Bicyclic Isoxazoline Derivatives: Synthesis and Evaluation of Biological Activity.

The application of non-planar scaffolds in drug design allows for the enlargement of the chemical space, and for the construction of molecules that have more effective target-ligand interactions or are less prone to the development of resistance. Among the works of the last decade, a literature search revealed spirothiazamenthane, which has served as a lead in the development of derivatives active against resistant viral strains. In this work, we studied the novel molecular scaffold, which resembles spirothiazamenthane, but combines isoxazoline as a heterocycle and cyclooctane ring as a hydrophobic part of the structure.

Synthesis of isomeric 4-(-methyltetrazolylamino)-2-phenyl-4-thiopyrano[2,3-]quinoline-3-carbaldehydes and 4-hydroxy-2-phenyl-4-thiopyrano[2,3-]quinoline-3-carbaldehyde based on tandem thiol-Michael and (aza)-Morita-Baylis-Hillman reactions and an study of the activity of the obtained compounds against influenza virus.

Unlabelled: 3-{[(1-Methyl-1-tetrazol-5-yl)imino]methyl}quinoline-2-thiol and 3-{[(2-methyl-2-tetrazol-5-yl)imino]methyl}quinoline-2-thiol were synthesized. The sequence of the thiol-Michael reaction and the (aza)-Morita-Baylis-Hillman reaction yielded 4-[(1-methyl-1-tetrazol-5-yl)amino]-2-phenyl-4-thiopyrano[2,3-]quinoline-3-carbaldehyde, 4-[(2-methyl-2-tetrazol-5-yl)amino]-2-phenyl-4-thiopyrano[2,3-]-quinoline-3-carbaldehyde, and 4-hydroxy-2-phenyl-4-thiopyrano[2,3-]quinoline-3-carbaldehyde. Cytotoxicity and antiviral activity against the A/Puerto Rico/8/34 (H1N1) influenza virus strain in MDCK cell culture were determined for the obtained compounds.

[Comparative analysis of residual neurovirulence of vaccine and low attenuated rubella virus (Matonaviridae: Rubivirus: Rubella virus) strains in the experiments on the macaque rhesus (Macaca mulatta) monkeys].

Introduction: Rubella is currently an infection controlled by specific prophylaxis. Not only the right vaccine prophylaxis strategy and tactics, but also the use of effective and safe vaccine preparations is crucial for the elimination of this disease.The aim of the investigation was to study the morphological and pathogenetic patterns of changes developing in the central nervous system (CNS) and internal organs of monkeys (Haplorhini) during intracerebral inoculation with 2 strains of rubella virus (Matonaviridae: Rubivirus: Rubella virus) (RV): highly attenuated Orlov-B, and low attenuated Orlov-14.

Polyfluoroalkylated antipyrines in Pd-catalyzed transformations.

In the direct C-H arylation with arylhalogenides in the presence of Pd(OAc), trifluoromethyl-containing antipyrine reacts very slowly and incompletely owing to the low nucleophilicity of its C4 center. However, it was effective in modifying polyfluoroalkyl-substituted 4-bromo- and 4-iodo antipyrines by the Suzuki and Sonogashira reactions. It was established that using Pd(dba) as catalyst and XPhos as phosphine ligand was the optimal catalytic system for the synthesis of 4-aryl- and 4-phenylethynyl-3-polyfluoroalkyl-antipyrines.

[Prevalence of viral hepatitis B markers among blood donors in the Republic of Guinea].

Introduction: The problem of transfusion safety in relation to parenteral viral hepatitis still remains relevant. Viral hepatitis B (HB) remains the most common viral infection transmitted through transfusion procedures. One of the natural phases of chronic hepatitis B (CHB) is occult hepatitis B infection (OBI), characterized by an undetectable HBsAg (regardless of the other serological markers content) in the presence of hepatitis B virus (HBV) DNA in the liver tissue and an extremely low, up to undetectable, level of viral load in the blood.

[Herd immunity to SARS-CoV-2 in the Novosibirsk Region population amid the COVID-19 pandemic].

Aim: To determine the level of SARS-CoV-2 seroprevalence among the Novosibirsk Region population against the background of the COVID-19 pandemic.

Material And Methods: The work was carried out in 2 phases: 1) a cross-sectional cohort study performed 28.06- 15.

Hemolytic Activity, Cytotoxicity, and Antimicrobial Effects of Human Albumin- and Polysorbate-80-Coated Silver Nanoparticles.

In this study, we aimed to develop a technique for colloidal silver nanoparticle (AgNP) modification in order to increase their stability in aqueous suspensions. For this purpose, 40-nm spherical AgNPs were modified by the addition of either human albumin or Tween-80 (Polysorbate-80). After detailed characterization of their physicochemical properties, the hemolytic activity of the nonmodified and modified AgNPs was investigated, as well as their cytotoxicity and antimicrobial effects.

Synthesis, structure, and antiviral properties of novel 2-adamantyl-5-aryl-2-tetrazoles.

Unlabelled: The reaction of 5-aryl--tetrazoles with adamantan-1-ol in concentrated sulfuric acid proceeds regioselectively with the formation of the corresponding 2-adamantyl-5-aryl-2-tetrazoles. Nitration of these compounds leads to 2-(adamantan-1-yl)-5-(3-nitroaryl)-2tetrazoles. The structures and composition of the obtained novel 2-adamantyl-5-aryltetrazoles were proven by IR spectroscopy, H and C NMR spectroscopy, high-resolution mass spectrometry, and also by X-ray structural analysis.

Synthesis and antiviral activity of nonannulated tetrazolylpyrimidines.

Nonannulated tetrazolylpyrimidines in the structure of which the heterocyclic fragments are separated by hydrazinocarbonylmethyl, methylpyrazolyl groups or a sulfur atom were synthesized. Some of these compounds showed moderate activity against H1N1 subtype of influenza A virus. The selectivity index of the anti-influenza action of {5-[(4,6-dimethylpyrimidin-2-yl)sulfanyl]-1-tetrazol-1-yl}acetic acid, which has very low cytotoxicity, was twice as high as the selectivity index of the reference drug rimantadine.

Methods of Synthesis and Antiviral Activity of New 4-Alkyl-3-Nitro-1,4-Dihydroazolo[5,1-][1,2,4]Triazin-4-ols.

Unlabelled: An azo coupling reaction of α-nitro ketones with 5-diazoazoles was used to obtain 4-alkyl-3-nitro-1,4-dihydroazolo[5,1-][1,2,4]triazines, which were characterized with respect to their antiviral activity against influenza and Coxsackie B3 viruses.

Supplementary Information: The online version contains supplementary material available at 10.1007/s10593-021-02926-2.

Design of a randomized controlled trial of smoking cessation medications for alcohol reduction among HIV-positive heavy drinkers and daily smokers in St. Petersburg, Russia.

Background: HIV, heavy drinking, and smoking are all pro-inflammatory and increase risk for coronary heart disease (CHD). Interventions that reduce alcohol use, smoking, or both in HIV-positive people could lower inflammation, CHD and death risk. Varenicline and cytisine are proven therapies for smoking cessation and may also reduce alcohol consumption.

Study of the teratogenicity of the vaccine strain of the Rubella virus «Orlov-V» (Matonaviridae: Rubivirus: Rubella virus) in experience on rhesus macaques.

Introduction: Rubella virus has pronounced teratogenic properties that can cause generalized and persistent intrauterine infection of the fetus. As a result, the control of the loss of teratogenicity inherent in «wild-type» virus strains is a necessary stage of a preclinical study of the vaccine strain for a live attenuated rubella vaccine.The purpose of the study is to comprehensively study the teratogenic properties of the vaccine strain of rubella virus «Orlov-V» in the experiment on rhesus macaques.

Serological diagnosis and prevalence of HIV-1 infection in Russian metropolitan areas.

Background: HIV infection is a major health problem in Russia. We aimed to assess HIV prevalence in different population groups and to compare the characteristics of 4th generation immunoassays from Abbott, Bio-Rad, Vector-Best, Diagnostic Systems, and Medical Biological Unit.

Methods: The study included 4452 individuals from the general population (GP), 391 subjects at high risk of HIV infection (HR) and 699 with potentially interfering conditions.

A strengths-based case management intervention to link HIV-positive people who inject drugs in Russia to HIV care.

Objective: To determine whether the Linking Infectious and Narcology Care strengths-based case management intervention was more effective than usual care for linking people who inject drugs (PWID) to HIV care and improving HIV outcomes.

Design: Two-armed randomized controlled trial.

Setting: Participants recruited from a narcology hospital in St.

Role of substance use in HIV care cascade outcomes among people who inject drugs in Russia.

Background: Engaging people who drink alcohol or inject drugs in HIV care can be challenging, particularly in Eastern Europe. Healthcare facilities in Russia are organized by specialty; therefore linking patients from addiction care to HIV hospitals has been difficult. The HIV care cascade outlines stages of HIV care (e.