Chloramine‐T Mediated Facile One Pot Synthesis of Pyrazolyltriazolobenzothiazole Hybrids as Potent Anti‐Infective Agents

Modified low-temperature synthesis of graphene oxide nanosheets: Enhanced adsorption, antibacterial and antioxidant properties

Herein, we report a simple, low-temperature, ecofriendly synthesis of graphene oxide nanosheets (GONs). Graphite powder was treated with KMnO₄ and a concentrated H₂SO₄/H₃PO₄ mixture to synthesize GONs. The effects of various reaction conditions such as reaction time, temperature, amounts of cleaving agents (H₂SO₄/H₃PO₄), and oxidant (KMnO₄) were investigated. The synthesized GONs were examined by various techniques in order to investigate their characteristics. The best results of the synthesized GONs were observed at 35 °C within 10 h of reaction time having 8:2 ratios of H₂SO₄/H₃PO₄ acid mixture. The main absorption peak in the UV-vis spectra of GONs was at 258 nm, which is due to the π-π* transition of the atomic CC bonds. The existence of stretching vibrations of C꞊O, O-H, C-H, and C-O in the Fourier transform infrared (FTIR) spectra verified the formation of GONs. Presence of a sharp peak at 2θ = 10° with an interlayer spacing distance of 0.88 nm in the observed XRD pattern revealed that the synthesized GONs were totally oxidized and that the interlayer spacing increased. The morphological investigations confirmed the formation of ultrathin, transparent, curly, and homogenous GONs. The synthesized GONs were applied as an adsorbent for the rapid uptake of four different pesticides viz.; Profenofos, Ethion, Cypermethrin, Thiamethoxam (TMX) from the pesticides spiked water samples. About 86% adsorption of Profenofos + Cypermethrin, and 50% adsorption of ethion and thiamethoxam took place within 20 min in presence of 10 mg GONs. In addition to this, the prepared GONs were tested for the antibacterial activity against four bacterial strains by agar well diffusion method. The synthesized GONs provide a significant inhibition for gram -positive (Bacillus subtilis, and Staphylococcus aureus) and gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacterial strains. Moreover, the radical scavenging activities (RSA) of GONs were also checked and compared with Gallic acid as a standard. The obtained RSA of GONs was 60% in comparison to the 80% as of the standard Gallic acid at 1000 μg/mL concentration.

Current Perspective of Synthesis of Medicinally Relevant Benzothiazole Based Molecules: Potential for Antimicrobial and Anti-Inflammatory Activities

The therapeutic potential of the majority of the marketed drugs is due to the presence of a heterocyclic nucleus, which constitutes a huge role in the field of medicinal chemistry. These heterocyclic scaffolds could act as a template in order to design potential therapeutic agents against several diseases. Benzothiazole scaffold is one of the influential heteroaromatic rings in the field of medicinal chemistry owing to its extensive pharmacological features. Herein, we have focused on the synthesis of benzothiazole based medicinal molecules, which possess antimicrobial and anti-inflammatory activities. This review covers a systematic description of synthetic routes for biologically relevant benzothiazole derivatives in the last five years. The main aim of this study is to show the diversification of benzothiazole based molecules into their pharmacologically more active derivatives. This review's synthetic protocols include metal-free, metal-catalyzed, and metal precursor azo dyes strategies for the development of benzothiazole derived bioactive compounds. The discussion under the various headings covers synthetic schemes and biological activities of the most potent molecules in the form of minimum inhibitory concentration.

Diacetoxy iodobenzene mediated regioselective synthesis and characterization of novel [1,2,4]triazolo[4,3-a]pyrimidines: apoptosis inducer, antiproliferative activities and molecular docking studies

Prompt and regioselective synthesis of eleven novel [1,2,4]triazolo[4,3-a]pyrimidines 2a-2k, via intramolecular oxidative-cyclization of 2-(2-arylidenehydrazinyl)-4-methyl-6-phenylpyrimidine derivatives 1a-1k has been demonstrated here using diacetoxy iodobenzene (DIB) as inexpensive and ecofriendly hypervalent iodine(III) reagent in CH₂Cl₂ at room temperature. Regiochemistry of final product has been established by developing single crystal and studied X-ray crystallographic data for two derivatives 2c and 2h without any ambiguity. These prominent [1,2,4]triazolo[4,3-a]pyrimidines were evaluated for human osteosarcoma bone cancer (MG-63) and breast cancer (MCF-7) cell lines using MTT assay to find potent antiproliferative agent and also on testicular germ cells to find potent apoptotic inducing activities. All compounds show significant cytotoxicity, particularly 3-(2,4-dichlorophenyl)-5-methyl-7-phenyl-[1,2,4]triazolo[4,3-a]pyrimidine (2g) was found significant apoptotic inducing molecule, as well as the most potent cytotoxic agent against bone cancer (MG-63) and breast cancer (MCF-7) cell lines with GI₅₀ value 148.96 µM and 114.3 µM respectively. Molecular docking studies has been carried out to see the molecular interactions of synthesized compounds with the protein thymidylate synthase (PBD ID: 2G8D).Communicated by Ramaswamy H. Sarma.