Design, Synthesis and Computational Studies of Novel Carbazole N-phenylacetamide Hybrids as Potent Antibacterial, Anti-inflammatory, and Antioxidant Agents

Preparation and property analysis of antioxidant of carbazole derivatives

Carbazole derivatives can be used as antioxidants in the lubricating oil industry. The alkylation of carbazole with 2-chloro-2-methylpropane and 2-bromopropane catalyzed by anhydrous aluminum chloride was studied. Initially, 3,6-di-iso-propylcarbazole and 3,6-di-tert-butylcarbazole were using dichloromethane and dibromomethane as solvents at room temperature, respectively. The synthesis conditions were optimized. Subsequently, the effects of reaction time, catalyst dosage, and molar ratio of carbazole to alkylating agent were investigated, and orthogonal experiments were performed. The structures of the carbazole derivatives were characterized by Fourier infrared spectroscopy (FT-IR), mass spectrum (MS) and nuclear magnetic resonance spectroscopy (NMR). The thermal stability of the synthesized carbazole derivatives was investigated by differential scanning calorimetry (DSC). The carbazole derivatives were added into the lubricating oil with a mass fraction of 0.8% and the miscibility, stability and oxidation resistance of the mixed system were evaluated by mechanical stirring and a rotary pressure vessel oxidation test (RPVOT). The DSC results showed that there was good thermal stability for the carbazole derivatives. The mechanical stirring method revealed good solubility and stability for the mixture of oil and carbazole derivatives. The RPVOT results showed that isopropyl carbazole derivatives could increase the oxidation induction period of lubricating oil to 1.39 times, and tert-butyl carbazole derivatives could increase the oxidation induction period of lubricating oil to 1.91 times. The antioxidant effect of tert-butyl carbazole derivatives was better than that of isopropyl carbazole derivatives.

Investigations of new N1-substituted pyrazoles as anti-inflammatory and analgesic agents having COX inhibitory activity

Background: The search is ongoing for ideal anti-inflammatory and analgesic agents with promising potency and reasonable selectivity. Methods: New N1-substituted pyrazoles with or without an acetamide linkage were synthesized and evaluated for their anti-inflammatory and analgesic activities. COX inhibitory testing, molecular docking, molecular dynamics simulation and antiproliferative activity assessments were performed. Results: All compounds exhibited anti-inflammatory activity up to 90.40% inhibition. They also exhibited good analgesic activity with up to 100% protection. N1-benzensulfonamides 3d, 6c and 6h were preferentially selective agents toward COX-2. Compound 3d showed good cytotoxicity against MCF-7 and HTC116 cancer cell lines. Molecular modeling studies predicted the binding pattern of the most active compounds. Molecular dynamics confirmed the docking results. All compounds showed remarkable pharmacokinetic properties.

5,12-Dihydroindolo[3,2-a]Carbazole Derivatives-Based Water Soluble Photoinitiators for 3D Antibacterial Hydrogels Preparation

Indolo[3,2-a]carbazole alkaloids have drawn a growing interest in recent years owing to their potential electrical and optical properties. With 5,12-dihydroindolo[3,2-a]carbazole serving as the scaffold, two novel carbazole derivatives are synthesized in this study. Both compounds are extremely soluble in water, with solubility surpassing 7% in weight. Intriguingly, the introduction of aromatic substituents contributed to drastically reduce the π-stacking ability of carbazole derivatives, while the presence of the sulfonic acid groups enables the resulting carbazoles remarkably soluble in water, allowing them to be used as especially efficient water-soluble PIs in conjunction with co-initiators, i.e., triethanolamine and the iodonium salt, respectively, employed as electron donor and acceptor. Surprisingly, multi-component photoinitiating systems based on these synthesized carbazole derivatives could be used for the in situ preparation of hydrogels containing silver nanoparticles via laser write procedure with a light emitting diode (LED)@405 nm as light source, and the produced hydrogels display antibacterial activity against Escherichia coli.

Antimicrobial activity of natural and semi-synthetic carbazole alkaloids

Since the first natural carbazole alkaloid, murrayanine, was isolated from Mwraya Spreng, carbazole alkaloid derivatives have been widely concerned for their anti-tumor, anti-viral and anti-bacterial activities. In recent decades, a growing body of data suggest that carbazole alkaloids and their derivatives have different biological activities. This is the first comprehensive description of the antifungal and antibacterial activities of carbazole alkaloids in the past decade (2012-2022), including natural and partially synthesized carbazole alkaloids in the past decade. Finally, the challenges and problems faced by this kind of alkaloids are summarized. This paper will be helpful for further exploration of this kind of alkaloids.

Antimicrobial Activity and Toxicity of Newly Synthesized 4-[4-(benzylamino)butoxy]-9H-carbazole Derivatives

One of the main challenges of medicinal chemistry is the search for new substances with antimicrobial potential that could be used in the fight against pathogenic microorganisms. Therefore, the antimicrobial activity of newly synthesized compounds is still being investigated. Carbazole-containing compounds appear to be promising antibacterial, antifungal, and antiviral agents. The aim of this study was to examine the antimicrobial potential and toxicity of newly synthesized isomeric fluorinated 4-[4-(benzylamino)butoxy]-9H-carbazole derivatives. Their antimicrobial activity against bacteria and fungi was tested according to CLSI guidelines. Similarly to previously studied carbazole-containing compounds, the tested derivatives showed the ability to effectively inhibit the growth of Gram-positive bacteria. The addition of carbazole derivatives 2, 4, and 8 at the concentration of 16 µg/mL caused the inhibition of S. aureus growth by over 60%. The MIC value of compounds 2-5 and 7-10 was 32 µg/mL for Staphylococcus strains. Gram-negative strains of E. coli and P. aeruginosa were found to be more resistant to the tested carbazole derivatives. E. coli cells treated with compounds 3 and 8 at a concentration of 64 µg/mL resulted in a greater-than-40% reduction in bacterial growth. In the case of the P. aeruginosa strain, all compounds in the highest concentration that we tested limited growth by 35-42%. Moreover, an over-60% inhibition of fungal growth was observed in the cultures of C. albicans and A. flavus incubated with 64 µg/mL of compounds 2 or 7 and 1 or 4, respectively. The hemolysis of red blood cells after their incubation with the tested carbazole derivatives was in the range of 2-13%. In the case of human fibroblast cells, the toxicity of the tested compounds was higher. Derivative 1, functionalized with fluorine in position 2 and its hydrobromide, was the least toxic. The obtained results indicated the antimicrobial potential of the tested 4-[4-(benzylamino)butoxy]-9H-carbazole derivatives, especially against S. aureus strains; therefore, it is worth further modifying these structures, in order to enhance their activity against pathogenic microorganisms.

In Silico and Experimental Investigation of the Biological Potential of Some Recently Developed Carprofen Derivatives

The efficient regioselective bromination and iodination of the nonsteroidal anti-inflammatory drug (NSAID) carprofen were achieved by using bromine and iodine monochloride in glacial acetic acid. The novel halogenated carprofen derivatives were functionalized at the carboxylic group by esterification. The regioselectivity of the halogenation reaction was evidenced by NMR spectroscopy and confirmed by X-ray analysis. The compounds were screened for their in vitro antibacterial activity against planktonic cells and also for their anti-biofilm effect, using Gram-positive bacteria (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212) and Gram-negative bacteria (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853). The cytotoxic activity of the novel compounds was tested against HeLa cells. The pharmacokinetic and pharmacodynamic profiles of carprofen derivatives, as well as their toxicity, were established by in silico analyses.

Modulation of DNA damage response by targeting ATM kinase using newly synthesized di-phenoxy acetamide (DPA) analogs to induce anti-neoplasia

BACKGROUND

Imbalance and instability in the structure of the DNA have become major characteristics of cancer. In response to DNA damage, DNA damage response (DDR) protein, ataxia telangiectasia mutated (ATM), plays a pivotal role in the modulation of regulatory regions responsible for inhibition of apoptosis, thereby neoplastic progression.

METHODS

A new series of DPA (7a-t) were synthesized, characterized. Anti-proliferative studies to identify the lead compound were carried out by LDH and MTT assay. Apoptosis/DNA damage was measured through FACS, Annexin-v staining, TUNEL and Comet assay. Elucidation of molecular mechanism through immunoblot and further validation of the drug effect through in vivo approaches.

RESULTS

Initial in vitro anti-proliferative screening of Compounds DPA (7a-t) against multiple cancer cell lines identified Compound DPA (7n) as a potent cytotoxic molecule with IC₅₀ value of 4.3 μM. Down the line, in vitro and in vivo evaluation of Compound DPA (7n) inferred that it has apoptotic inducing potentiality. Further, evaluation of molecular mechanism inferred that Compound DPA (7n) effectively modulates ATM phosphorylation only, eventually altering downstream signalling pathways.

CONCLUSIONS

Compound DPA (7n) emerged as a potent proapoptotic and anti-neoplastic agent by inhibiting ATM kinase activity both in vitro and in vivo. The conferring results ascertain that the drug could be developed as a new ATM kinase inhibitor with anti-cancer capacity.