Utilization of bromine azide to access vicinal-azidobromides from arylidene malononitrile

Synthesis of New Binary Thiazole-Based Heterocycles and Their Molecular Docking Study as COVID-19 Main Protease (Mpro) Inhibitors

Isolated polynuclear binary heterocyclic compounds containing thiazole building block combined with benzofuran, pyrrole, thiazole, or thiophene via carboxamide and/or secondary amine as a junction are presented. The synthetic strategy of those is based on utilization of 2-chloroacetamido-4-phenylthiazole in the synthesis of binary heterocyclic compounds by cyclocondensation with salicylic aldehyde, acetonitrile derivatives, ammonium thiocyanate, 3-mercaptoacrylonitrile derivatives, and/or 3-mercaptoacrylate derivatives. The prepared binary thiazole-based heterocycles have been studied as protease (M^pro) inhibitors by molecular docking for visualization of their orientation and interactions with COVID-19 units using hydroxychloroquine as a reference molecule.

Biological Evaluation and Molecular Docking with In Silico Physicochemical, Pharmacokinetic and Toxicity Prediction of Pyrazolo[1,5-a]pyrimidines

Pyrazolo[1,5-a]pyrimidines 5a–c, 9a–c and 13a–i were synthesized for evaluation of their in vitro antimicrobial properties against some microorganisms and their immunomodulatory activity. The biological activities of pyrazolo[1,5-a]pyrimidines showed that the pyrazolo[1,5-a]pyrimidines (5c, 9a, 9c, 13a, 13c, 13d, 13e and 13h) displayed promising antimicrobial and immunomodulatory activities. Studying the in silico predicted physicochemical, pharmacokinetic, ADMET and drug-likeness properties for the pyrazolo[1,5-a]pyrimidines 5a–c, 9a–c and 13a–i confirmed that most of the compounds (i) were within the range set by Lipinski’s rule of five, (ii) show higher gastrointestinal absorption and inhibition of some CYP isoforms, and (iii) have a carcinogenicity test that was predicted as negative and hERG test that presented medium risk. Moreover, the molecular docking study demonstrated that the compounds 5c, 9a, 9c, 13a, 13c, 13d, 13e and 13h are potent inhibitors of 14-alpha demethylase, transpeptidase and alkaline phosphatase enzymes. This study could be valuable in the discovery of a new series of drugs.

Iron-Catalyzed Asymmetric Haloazidation of α,β-Unsaturated Ketones: Construction of Organic Azides with Two Vicinal Stereocenters

Organic azides play important roles in synthetic chemistry, chemical biology, drug discovery, and material science. Azido-functionalization of alkenes is one of the most efficient procedures for rapid introduction of azide group into organic compounds. But only a few examples have been documented in the catalytic asymmetric version of the azidation of alkenes. Herein, we report an unprecedented highly diastereo- and enantioselective bromoazidation of α,β-unsaturated ketones catalyzed by chiral N,N'-dioxide/Fe(OTf)₂ complexes. An array of aryl, heteroaryl, and alkyl substituted α,β-unsaturated ketones were transformed to the corresponding α-bromo-β-azido ketones in high yields with excellent diastereo- and enantioselectivities. The catalytic system was also applicable for chloroazidation and iodoazidation of chalcone. Kinetic studies and some control experiments suggested that the reaction might proceed via a 1,4-addition/halogenation pathway.

Electronic halocyclization and radical haloazidation of benzene-linked 1,7-dienes for the synthesis of functionalized 3,1-benzoxazines

Electronic halocyclization and radical haloazidation of benzene-linked 1,7-dienes by using TMSN₃ as an azidyl source and NBS as a halogen source has been disclosed in this paper, producing a series of functionalized 3,1-benzoxazines in moderate to good yields.