ABSTRACT
A convenient and facile synthesis of a privileged pharmaceutical scaffolds, 2,5-bis(substituted thio)-1,3,4-thiadiazoles is accomplished. The reaction of hydrazine hydrate with carbon disulfide and substituted alkyl/aryl chloride in basic medium yielded S-substituted alkyl/aryl dithiocarbazates in high yield. These dithiocarbazates on reaction with tetrafluoro acetic acid underwent a unique acid catalyzed intermolecular cyclization reaction to afford a novel 2,5-bis(substituted thio)-1,3,4-thiadiazoles. A simple procedure and high yields are the characteristic features of these reactions. These compounds are characterized on the basis of physico-chemical and spectral (FT-IR, ESI Mass, 1H, 13C and DEPT 135° 13C {1H} NMR) studies. Compound 2b crystallizes in orthorhombic system with point group P bca. Using the DFT/B3LYP/6–311 G (d,p) level of theory, HOMO-LUMO energy gap and molecular electrostatic potential (MEP) analyses were carried out. The HOMO-LUMO energy gap allowed the calculation of chemical hardness, chemical inertness, electronegativity and the electrophilicity index of the molecule, which depicted their potential kinetic stability and reactivity. The molecular docking studies of 2b-2e with 2019-nCoV main protease(7BRO) revealed binding free energies of (ΔGb) = -6.22, -5.38, -4.43 and -4.25 kcal mol−1 respectively. Docking study revealed that the aromatic congeners exhibit appreciable therapeutic efficiency to be used as 2019-nCoV main protease inhibitors. © 2021 Elsevier B.V.
ABSTRACT
With the COVID-19 outbreak, many challenges are posed before the scientific world to curb this pandemic. The diagnostic testing, treatment, and vaccine development for this infection caught the scientific community's immediate attention. Currently, despite the global proliferation of COVID-19 vaccination, the specific treatment for this disease is yet unknown. Meanwhile, COVID-19 detection or diagnosis using polymerase chain reaction (PCR)-based me hods is expensive and less reliable. Moreover, this technique needs much time to furnish the results. Thus, the elaboration of a highly sensitive and fast method of COVID-19 diagnostics is of great importance. The spectroscopic approach is herein suggested as an efficient detection methodology for COVID-19 diagnosis, particularly Raman spectroscopy, infrared spectroscopy, and mass spectrometry.
ABSTRACT
In the prevailing apocalyptic times of coronavirus disease (COVID-19), the whole scientific community is busy in designing anticovid drug or vaccine. Under such a fascination, Schiff bases or azomethine compounds are continuously interrogated for antimicrobial properties. These compounds represent interesting molecular scaffolds of huge medicinal and industrial relevance. In order to update the current literature support of such facts this article introduces the synthetic chemistry, mechanism of formation of a Schiff base, followed by biological efficacy and finally a suitable discussion on the mechanism of respective bioactivity. In most of the studies revealing the biological evaluation of azomethine functionalized frameworks, fascinated results have been recorded in case of azomethine-metal complexes as compared with the free ligands. Also, the CH=N or C=N form of organic ligands have indicated marvellous results. Therefore, in connection with the biological relevance and microbicidal implications of such metallic compounds, this works reviews the current update of microorganism fighting efficacy of azomethine metal complexes along with the introduction of some metallodrugs as excellent candidates having COVID-19 defending potentiality. © 2021 Walter de Gruyter GmbH, Berlin/Boston 2021.