Synthesis and antinociceptive activity of (5-chloro-2-benzothiazolinon-3-yl)acetamide derivatives

Metal-Free Temperature-Controlled Intermolecular [3 + 2] Annulation to Access Benzo[d]thiazole-2(3H)-thiones and Benzo[d]thiazol-2(3H)-ones

A facile access to benzo[d]thiazole-2(3H)-thiones and benzo[d]thiazol-2(3H)-ones has been developed through a temperature-controlled intermolecular [3 + 2] annulation of N,N-disubstituted arylhydrazines with CS₂ in the presence of DMSO. This protocol can obviate the prefunctionalization of the starting materials. This direct C-S/C-N bond formation reaction was performed in the absence of any external catalysts, transition metals, bases, ligands, and oxidants with high step economy.

Synthesis of Thiazole-2(3H)-ones via [3,3]-Sigmatropic Rearrangement/5-exo-dig Cyclization of N-Propargylamines

An efficient methodology has been developed for the synthesis of both di- and trisubstituted thiazol-2(3H)-ones from N-propargylamines and silver(I) trifluoromethanethiolate (AgSCF₃) in good yields. The reaction proceeds via [3,3]-sigmatropic rearrangement/5-exo-dig cyclization of N-propargylamines. The starting material can be easily prepared from the A³-coupling reaction of amines, aldehydes, and alkynes. The methodology can be extended for the synthesis of thiozole-2(3H)-thione derivatives, and photophysical properties have been studied for some synthesized compounds.

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.

ZnO nanoparticles supported on dendritic fibrous nanosilica as efficient catalysts for the one-pot synthesis of quinazoline-2,4(1H,3H)-diones

The transmutation of waste into valuable materials has a special place in green chemistry. Herein, we report the preparation of quinazoline-2,4(1H,3H)-diones from 2-iodoaniline, isocyanides, and carbon dioxide in the presence of ZnO NPs stably placed on the surface of dendritic fibrous nanosilica by cellulose (DFNS/cellulose-ZnO) as a catalyst. This is a great economic strategy to create three bonds in a one-pot multicomponent reaction step employing functional groups. To prepare the catalyst, the dendritic fibrous nanosilica surface was first activated using cellulose as a substrate to support ZnO NPs. Cellulose acts as a stabilizing and reducing agent for the ZnO nanocatalyst and eliminates the need for a reducing agent. The structure of the prepared DFNS/cellulose-ZnO was examined by various methods, including thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma (ICP). The largest amount of quinazoline-2,4(1H,3H)-diones was obtained under ideal situations in the presence of 5 mg of DFNS/cellulose-ZnO under carbon dioxide (1 atm) utilizing a balloon set at 70 °C for 3 hours. The substance was reused for ten consecutive runs and the quinazoline-2,4(1H,3H)-dione content was more than 92% each time. This indicates the potential for application in the green and economic production of quinazoline-2,4(1H,3H)-diones, especially from low-cost feedstocks.

The transmutation of waste into valuable materials has a special place in green chemistry.

Synthesis and anti-inflammatory activity of certain piperazinylthienylpyridazine derivatives

In this study, a novel series of 2-(4-substituted piperazin-l-ylmethyl)-6-(thien-2-yl)-2H-pyridazin-3-ones (3a-f), 2-(4-substituted piperazin-l-yl carbonylmethyl)-6-(thien-2-yl)-2H-pyridazin-3-ones (4a-c) and 2-[2-(4-substituted piperazin-l-ylcarbonylethyl)]-6-(thien-2-yl)-2H-pyridazin-3-ones (5a,b) were prepared from 6-(thien-2-yl)-2H- pyridazin-3-one (1). In addition, 3-(4-substituted piperazin-l-ylcarbonyl methyl thio)-6-(thien-2-yl) pyridazines (6a-c) and 3-[2-(4-substitutedpiperazin-1-ylcarbonyl ethylthio]-6-(thien-2-yl) pyridazines (7a,b) were synthesized. Furthermore, 5-(4-substituted piperazin-l-ylmethyl)-6-(thien-2-yl)-2H-pyridazin-3-ones (12a,b) were prepared. The structures of the new compounds were confirmed by elemental analysis as well as by 1H-NMR, IR and MS data. Some of the newly prepared compounds were subjected to evaluation for their anti-inflammatory activity against carrageenan-induced paw edema at a dose of 10 mg/kg using indomethacin as the reference standard.

Synthesis and antinociceptive activity of (5-chloro-2(3H)-benzoxazolon-3-yl) propanamide derivatives

In this study, (5-chloro-2(3H)-benzoxazolon-3-yl)propanamide derivatives were synthesized. The chemical structures of the compounds were elucidated by their IR and 1H-NMR spectral data and microanalysis. The compounds were tested for antinociceptive activity by using the tail clip, tail flick, hot plate, and writhing methods. The varying levels of antinociceptive activity of the compounds were compared with those of dipyrone and aspirin. Among these compounds, compound 5e, 5g, and 5h have been found to be significantly more active than the others and the standards in all the tests.