The Efficacy of Aprotinin Combinations with Selected Antiviral Drugs in Mouse Models of Influenza Pneumonia and Coronavirus Infection Caused by SARS-CoV-2.

The efficacy of aprotinin combinations with selected antiviral-drugs treatment of influenza virus and coronavirus (SARS-CoV-2) infection was studied in mice models of influenza pneumonia and COVID-19. The high efficacy of the combinations in reducing virus titer in lungs and body weight loss and in increasing the survival rate were demonstrated. This preclinical study can be considered a confirmatory step before introducing the combinations into clinical assessment.

Safety and efficacy of aviandr in patients with generalized anxiety disorder: A multicenter, randomized, double-blind, placebo-controlled, dose-finding, pilot study.

Generalized anxiety disorder (GAD) is associated with an imbalance in the functioning of the stimulating neurotransmitter systems in human's brain. We studied the safety and therapeutic efficacy of aviandr, the new noradrenergic and specific serotonergic antidepressant, for GAD patients in the phase II, double-blind, placebo-controlled, randomized, multicenter, pilot trial at 17 clinical sites of the Russian Federation. 129 eligible patients were 18 years and older and met the criteria for GAD diagnosis. The patients were randomly assigned (1:1:1) to receive oral aviandr at daily dose of 40 mg (cohort 1, n = 41) or 60 mg (cohort 2, n = 43) or placebo (cohort 3, n = 43) for 8 weeks. The patients were assessed by the Hamilton anxiety scale (HAM-A), Hamilton Depression Scale (HAM-D), Clinical Global Impression Scale (CGI-S), Visual Analogue Scale and vital signs. At week 8, the decreases of the HAM-A score were achieved in 53∙7%, 47∙7% and 16∙3% in cohorts 1, 2 and 3, respectively. Changes of HAM-A, HAM-D, CGI-S, and CGI-I scores in aviandr-treated patients were superior to placebo (p < 0∙001). The psychic components of anxiety decreased on the first day, throughout the 8 weeks of treatment and on a follow-up week after aviandr discontinuation. Aviandr (40 mg daily dose) reduced drowsiness compared to baseline, was safe, well-tolerated and did not cause serious or severe adverse events or signs of withdrawal syndrome within one week after treatment completion. Aviandr at both 40 and 60 mg daily doses demonstrated therapeutic efficacy in GAD patients over placebo.

Effect of Aprotinin and Avifavir® Combination Therapy for Moderate COVID-19 Patients.

COVID-19 is a contagious multisystem inflammatory disease caused by a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We studied the efficacy of Aprotinin (nonspecific serine proteases inhibitor) in combination with Avifavir® or Hydroxychloroquine (HCQ) drugs, which are recommended by the Russian Ministry of Health for the treatment therapy of moderate COVID-19 patients. This prospective single-center study included participants with moderate COVID-19-related pneumonia, laboratory-confirmed SARS-CoV-2, and admitted to the hospitals. Patients received combinations of intravenous (IV) Aprotinin (1,000,000 KIU daily, 3 days) and HCQ (cohort 1), inhalation (inh) treatment with Aprotinin (625 KIU four times per day, 5 days) and HCQ (cohort 2) or IV Aprotinin (1,000,000 KIU daily for 5 days) and Avifavir (cohort 3). In cohorts 1-3, the combination therapy showed 100% efficacy in preventing the transfer of patients (n = 30) to the intensive care unit (ICU). The effect of the combination therapy in cohort 3 was the most prominent, and the median time to SARS-CoV-2 elimination was 3.5 days (IQR 3.0-4.0), normalization of the CRP concentration was 3.5 days (IQR 3-5), of the D-dimer concentration was 5 days (IQR 4 to 5); body temperature was 1 day (IQR 1-3), improvement in clinical status or discharge from the hospital was 5 days (IQR 5-5), and improvement in lung lesions of patients on 14 day was 100%.

Crystal structure of the non-steroidal anti-inflammatory drug (NSAID) tolmetin sodium.

The asymmetric unit of the title compound, sodium 2-[1-methyl-5-(4-methyl-benzo-yl)-1H-pyrrol-2-yl]acetate dihydrate, Na+·C15H14NO3 -·2H2O, contains two sodium cations, two organic anions (A and B) and two water mol-ecules. The coordination geometry around the sodium cations corresponds to a distorted octa-hedron. Each pair of sodium cations (A-A or B-B) is chelated by two bridging anions coordinated by the O atoms of the deprotonated carb-oxy-lic groups, and each sodium atom is coordinated by an O atom of a third anion, which connects pairs of sodium atoms, and a water mol-ecule. As a result, a two-dimensional polymer is formed in the crystal. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to analyze the inter-molecular contacts present in the crystal.

Synthesis, inhibitory activity and oral dosing formulation of AV5124, the structural analogue of influenza virus endonuclease inhibitor baloxavir.

BACKGROUND: The development and clinical implementation of the cap-dependent endonuclease (CEN) inhibitor baloxavir marboxil was a breakthrough in influenza therapy, but it was associated with the emergence of drug-resistant variants. OBJECTIVES: To design and synthesize structural analogues of CEN inhibitors and evaluate their safety, pharmacokinetics and antiviral potency in vitro and in vivo. METHODS: The drug candidate AV5124 and its active metabolite AV5116 were synthesized based on pharmacophore modelling. Stability in plasma and microsomes, plasma protein binding, cytotoxicity and antiviral activities were assessed in vitro. Pharmacokinetics after IV or oral administration were analysed in CD-1 mice. Acute toxicity and protective efficacy against lethal A(H1N1)pdm09 influenza virus challenge were examined in BALB/c mice. RESULTS: Pharmacophore model-assisted, 3D molecular docking predicted key supramolecular interactions of the metal-binding group and bulky hydrophobic group of AV5116 with the CEN binding site (Protein Data Bank code: 6FS6) that are essential for high antiviral activity. AV5116 inhibited influenza virus polymerase complexes in cell-free assays and replication of oseltamivir-susceptible and -resistant influenza A and B viruses at nanomolar concentrations. Notably, AV5116 was equipotent or more potent than baloxavir acid (BXA) against WT (I38-WT) viruses and viruses with reduced BXA susceptibility carrying an I38T polymerase acidic (PA) substitution. AV5116 exhibited low cytotoxicity in Madin-Darby canine kidney cells and lacked mitochondrial toxicity, resulting in favourable selective indices. Treatment with 20 or 50 mg/kg AV5124 prevented death in 60% and 100% of animals, respectively. CONCLUSIONS: Overall, AV5124 and A5116 are promising inhibitors of the influenza virus CEN and warrant further development as potent anti-influenza agents.

AVIFAVIR for Treatment of Patients With Moderate Coronavirus Disease 2019 (COVID-19): Interim Results of a Phase II/III Multicenter Randomized Clinical Trial.

In May 2020 the Russian Ministry of Health granted fast-track marketing authorization to RNA polymerase inhibitor AVIFAVIR (favipiravir) for the treatment of COVID-19 patients. In the pilot stage of Phase II/III clinical trial, AVIFAVIR enabled SARS-CoV-2 viral clearance in 62.5% of patients within 4 days, and was safe and well-tolerated. Clinical Trials Registration. NCT04434248.

Synthesis, biological evaluation and in silico modeling of novel pan-genotypic NS5A inhibitors.

A series of novel small-molecule pan-genotypic hepatitis C virus (HCV) NS5A inhibitors with picomolar activity containing 2-[(2S)-pyrrolidin-2-yl]-5-[4-(4-{2-[(2S)-pyrrolidin-2-yl]-1H-imidazol-5-yl}buta-1,3-diyn-1-yl)phenyl]-1H-imidazole core was designed based on molecular modeling study and SAR analysis. The constructed in silico model and docking study provide a deep insight into the binding mode of this type of NS5A inhibitors. Based on the predicted binding interface we have prioritized the most crucial diversity points responsible for improving antiviral activity. The synthesized molecules were tested in a cell-based assay, and compound 1.12 showed an EC50 value in the range of 2.9-34 pM against six genotypes of NS5A HCV, including gT3a, and demonstrated favorable pharmacokinetic profile in rats. This lead compound can be considered as an attractive candidate for further clinical evaluation.

(1R,3S)-3-(1H-Benzo[d]imidazol-2-yl)-1,2,2-tri-methyl-cyclo-pentane-1-carb-oxy-lic acid as a new anti-diabetic active pharmaceutical ingredient.

The chiral title compound, C16H20N2O2, which can be used for producing active pharmaceutical ingredients for treatment of type 2 pancreatic diabetes and other pathologies dependent on insulin resistance, was prepared from (1R,3S)-camphoric acid and o-phenyl-enedi-amine. It crystallized from an ethanol solution in the chiral monoclinic P21 space group. The five-membered ring adopts a twisted conformation with the methyl-substituted C atoms displaced by -0.273 (5) and 0.407 (5) Šfrom the mean plane through the other three atoms. In the crystal, mol-ecules are linked by O-H⋯N hydrogen bonds, forming chains along the a-axis direction. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to analyze the inter-molecular contacts present in the crystal.

Methylation of Methyl 4-Hydroxy-2-thioxo-1,2-dihydroquinoline-3-carboxylate: Synthetic, Crystallographic, and Molecular Docking Studies.

Consecutive alkylation of 4-hydroxy-2-thioxo-1,2-dihydroquinoline-3-carboxylate by CH3I has been investigated to establish regioselectivity of the reaction for reliable design and synthesis of combinatorial libraries. In the first stage, the product of S-methylation-methyl 4-hydroxy-2-(methylthio)quinoline-3-carboxylate was obtained. The subsequent alkylation with CH3I led to the formation of both O- and N-methylation products mixture-methyl 4-methoxy-2-(methylthio)quinoline-3-carboxylate and methyl 1-methyl-2-(methylthio)-4-oxo-1,4-dihydroquinoline-3-carboxylate with a predominance of O-methylated product. The structure of synthesized compounds was confirmed by means of elemental analysis, 1H-NMR, 13C-NMR, LC/MS, and single-crystal X-ray diffraction. The quantum chemical calculations of geometry and electron structure of methyl 4-hydroxy-2-(methylthio)quinoline-3-carboxylate's anion were carried out. According to molecular docking simulations, the studied compounds can be considered as potent inhibitors of Hepatitis B Virus replication. Experimental in vitro biological studies confirmed that studied compounds demonstrated high inhibition of HBV replication in 10 µM concentration.

Non-rigid Diarylmethyl Analogs of Baloxavir as Cap-Dependent Endonuclease Inhibitors of Influenza Viruses.

4-Substituted 2,4-dioxobutanoic acids inhibit influenza virus cap-dependent endonuclease (CEN) activity. Baloxavir marboxil, 4, is approved for treating influenza virus infections. We describe here the synthesis and biological evaluation of active compounds, 5a-5g, and their precursors (6a, 6b, 6d, and 6e) with flexible bulky hydrophobic groups instead of the rigid polyheterocyclic moieties. In silico docking confirmed the ability of 5a-5g to bind to the active site of influenza A CEN (PDB code: 6FS6) like baloxavir acid, 3. These novel compounds inhibited polymerase complex activity, inhibited virus replication in cells, prevented death in a lethal influenza A virus mouse challenge model, and dramatically lowered viral lung titers. 5a and 5e potently inhibited different influenza genera in vitro. Precursors 6a and 6d demonstrated impressive mouse oral bioavailability with 6a, providing effective in vivo protection. Thus, these novel compounds are potent CEN inhibitors with in vitro and in vivo activity comparable to baloxavir.

Crystal structure, Hirshfeld analysis and a mol-ecular docking study of a new inhibitor of the Hepatitis B virus (HBV): ethyl 5-methyl-1,1-dioxo-2-{[5-(pentan-3-yl)-1,2,4-oxa-diazol-3-yl]meth-yl}-2H-1,2,6-thia-diazine-4-carboxyl-ate.

The title compound, C15H22N4O5S, was prepared via alkyl-ation of 3-(chloro-meth-yl)-5-(pentan-3-yl)-1,2,4-oxa-diazole in anhydrous dioxane in the presence of tri-ethyl-amine. The thia-diazine ring has an envelope conformation with the S atom displaced by 0.4883 (6) Šfrom the mean plane through the other five atoms. The planar 1,2,4-oxa-diazole ring is inclined to the mean plane of the thia-diazine ring by 77.45 (11)°. In the crystal, mol-ecules are linked by C-H⋯N hydrogen bonds, forming chains propagating along the b-axis direction. Hirshfeld surface analysis and two-dimensional fingerprint plots have been used to analyse the inter-molecular contacts present in the crystal. Mol-ecular docking studies were use to evaluate the title compound as a potential system that inter-acts effectively with the capsid of the Hepatitis B virus (HBV), supported by an experimental in vitro HBV replication model.

Synthesis, biological evaluation and in silico modeling of novel integrase strand transfer inhibitors (INSTIs).

Although a relatively wide range of therapeutic options is currently available for the treatment of HIV/AIDS, it is still among the most serious and virulent diseases and is associated with a high mortality rate. Integrase strand transfer inhibitors (INSTIs), e.g., FDA-approved dolutegravir (DTG), bictegravir (BIC) and cabotegravir (CAB), have recently been included in standard highly active antiretroviral therapy (HAART) schemes as one of the five major components responsible for the most beneficial clinical outcome. In this paper, we describe a combinatorial amide synthesis, biological evaluation and in silico modeling of new INSTIs containing heteroaromatic bioisosteric substitution instead of the well-studied halogen-substituted benzyl fragment. With the focus on the mentioned diversity point, a medium-sized library of compounds was selected for synthesis. A biological study revealed that many molecules were highly active INSTIs (EC50 < 10 nM). Two compounds 1{4} and 1{26} demonstrated picomolar antiviral activity that was comparable with CAB and were more active than DTG and BIC. Molecular docking study was performed to evaluate the binding mode of compounds in the active site of HIV-1 IN. In rats, lead compound 1{26} showed two-fold greater bioavailability than CAB and had a similar half-life. Compound 1{26} and its sodium salt were considerably more soluble in water than the parent drugs. Both molecules were very stable in human liver microsomes and plasma, demonstrated high affinity towards plasma proteins and did not show cytochrome (CYP) inhibition. This benefit profile indicates the great potential of these molecules as attractive candidates for subsequent evaluation as oral long-acting drugs and long-acting nanosuspension formulations for intramuscular injection.

Synthesis, X-ray crystal structure, Hirshfeld surface analysis, and molecular docking study of novel inhibitor of hepatitis B: methyl 4-fluoro-3-(morpholinosulfonyl)benzo[b]thiophene-2-carboxylate.

A method of 4-fluoro-3-(morpholinosulfonyl)benzo[b]thiophene-2-carboxylate synthesis has been developed and the electronic and spatial structure of a new biologically active molecule has been studied both theoretically and experimentally. The title compound was crystallized from acetonitrile and the single crystal X-ray analysis has revealed that it exists in a monoclinic P21/c space group, with one molecule in the asymmetric part of the unit cell. Hirshfeld surface analysis was used to study intermolecular interactions in the crystal. Molecular docking study evaluates the investigated compound as a new potential inhibitor of hepatitis B. Testing for anti-hepatitis B virus activity has shown that this substance demonstrates in vitro nanomolar inhibitory activity against HBV.

Design, synthesis and biological evaluation of novel 5-oxo-2-thioxoimidazolidine derivatives as potent androgen receptor antagonists.

A series of novel highly active androgen receptor (AR) antagonists containing spiro-4-(5-oxo-3-phenyl-2-thioxoimidazolidin-1-yl)-2-(trifluoromethyl)benzonitrile core was designed based on the SAR studies available from the reported AR antagonists and in silico modeling. Within the series, compound (R)-6 (ONC1-13B) and its related analogues, including its active N-dealkylated metabolite, were found to be the most potent molecules with the target activity (IC50, androgen-sensitive human PCa LNCaP cells) in the range of 59-80 nM (inhibition of PSA production). The disclosed hits were at least two times more active than bicalutamide, nilutamide and enzalutamide within the performed assay. Several compounds were classified as partial agonists. Hit-compounds demonstrated benefit pharmacokinetic profiles in rats. Comparative SAR and 3D molecular docking studies were performed for the hit compounds elucidating the observed differences in the binding potency.

Discovery of novel highly potent hepatitis C virus NS5A inhibitor (AV4025).

A series of next in class small-molecule hepatitis C virus (HCV) NS5A inhibitors with picomolar potency containing 2-pyrrolidin-2-yl-5-{4-[4-(2-pyrrolidin-2-yl-1H-imidazol-5-yl)buta-1,3-diynyl]phenyl}-1H-imidazole cores was designed based on the SAR studies available for the reported NS5A inhibitors. Compound 13a (AV4025), with (S,S,S,S)-stereochemistry (EC50 = 3.4 ± 0.2 pM, HCV replicon genotype 1b), was dramatically more active than were the compounds with two (S)- and two (R)-chiral centers. Human serum did not significantly reduce the antiviral activity (<4-fold). Relatively favorable pharmacokinetic features and good oral bioavailability were observed during animal studies. Compound 13a was well tolerated in rodents (in mice, LD50 = 2326 mg/kg or higher), providing a relatively high therapeutic index. During safety, pharmacology and subchronic toxicity studies in rats and dogs, it was not associated with any significant pathological or clinical findings. This compound is currently being evaluated in phase I/II clinical trials for the treatment of HCV infection.

Preclinical Development of ONC1-13B, Novel Antiandrogen for Prostate Cancer Treatment.

Recently new drugs targeting androgen-dependent axis have been approved for the treatment of castration-resistant prostate cancer (CRPC) - Zytiga and Xtandi (formerly MDV3100), several other candidates (for example, ARN-509) are in early phases of clinical trials. However despite significant improvement in overall survival with new treatments it is evident that resistance to these drugs develops. One of the approaches to overcome it is combination therapy and from this point of view some potential for drug-drug interactions can limit the application of the drug. We describe here the preclinical development of ONC1-13B, antagonist of androgen receptor, with similar to MDV3100 and ARN-509 mechanism of action. It efficiently inhibits DHT-stimulated PSA expression and proliferation of prostate cancer cells, prevents binding of androgens to the AR ligand-binding domain, androgen-stimulated AR nuclear translocation and coactivator complex formation. In the LnCaP-Z2 xenograft model of prostate cancer ONC1-13B inhibits tumor growth and suppresses PSA expression. The in vivo activity of ONC1-13B is comparable to that of MDV3100 at similar doses, and even higher, calculated per unit of concentration in plasma. Distribution of ONC1-13B to the brain is less than that shown for MDV3100 and ARN-509, decreasing the risk of GABA-related seizure development. Additionally ONC1-13B induces significantly lower in vitro CYP3A activity than for example MDV3100 (known strong CYP3A inducer) or ARN-509 and could be well suited for co-therapy with drugs that are known CYP3A substrates. Thus ONC1-13B is a new promising antiandrogen demonstrating high efficacy in a preclinical model of prostate cancer, with lower potential for seizures and drug-drug interaction.

Highly sensitive field test lateral flow immunodiagnostics of PVX infection.

A test system is described and expanded upon for mass field immunochromatography assay on porous membrane carriers for rapid diagnostics of potato virus X (PVX) in potato leaf tissue and sprout extracts using colloidal gold nanoparticles as a marker. Sensitivity of the assay developed for PVX identification is found to be comparable to the sensitivity of solid-phase sandwich-ELISA. Complete assay time does not exceed 15 min, and the lower limit of the PVX detection in non-clarified leaf extract is 2 ng/ml. A single measurement requires 0.1-0.2 ml (3-5 drops) of tested solution only (extracted from 10-20 mg of potato leaf tissue or sprouts). The simplicity and reliability of the method makes it especially efficient in direct rapid monitoring of many infected potato specimens in the field, as verified by field trials of 360 clones of 28 domestic and foreign cultivars of potato. A diagnostic kit for routine analyses of potato viral infections both in the laboratory and in the field is described and expanded upon.

Novel aryl and heteroaryl substituted N-[3-(4-phenylpiperazin-1-yl)propyl]-1,2,4-oxadiazole-5-carboxamides as selective GSK-3 inhibitors.

Synthesis, biological evaluation, and SAR dependencies for a series of novel aryl and heteroaryl substituted N-[3-(4-phenylpiperazin-1-yl)propyl]-1,2,4-oxadiazole-5-carboxamide inhibitors of GSK-3beta kinase are described. The inhibitory activity of the synthesized compounds is highly dependent on the character of substituents in the phenyl ring and the nature of terminal heterocyclic fragment of the core molecular scaffold. The most potent compounds from this series contain 3,4-di-methyl or 2-methoxy substituents within the phenyl ring and 3-pyridine fragment connected to the 1,2,4-oxadiazole heterocycle. These compounds selectively inhibit GSK-3beta kinase with IC(50) value of 0.35 and 0.41 microM, respectively.

Natural products as templates for bioactive compound libraries: synthesis of biaryl derivatives of (+/-)-vasicine.

A reliable and high-yielding procedure for preparation of 7-aryl and 7-heteroaryl derivatives of (+/-)-vasicine in two steps from the naturally occurring material is described. This protocol broadens the chemical space for selective modifications of the vasicine tricyclic structure, thereby making it a valuable starting point for the development of novel compound libraries with potentially beneficial biological profiles.

Natural products as templates for bioactive compound libraries: part 2. Novel modifications of vasicine (peganine) core via efficient and regioselective generation of 3-lithiodeoxyvasicine and its stereoselective addition to aliphatic ketones section sign.

A general procedure for direct lithiation of deoxyvasicine was developed. 3-Lithiodeoxyvasicine intermediate was found to react with various aliphatic ketones providing derivatives of 3-(hydroxyalkyl)deoxyvasicine in good yields. Similar reaction with 4-alkylcyclohexanones yielded respective trans-adducts exclusively. This novel protocol was successfully scaled-up to result in multigram quantities of vasicine-containing core building blocks suitable for production of compound libraries. The described synthetic methodology offers access to a wide range of compounds with potentially beneficial biological profiles.