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One‐pot synthesis of acetamides, benzimidazoles, and benzothiazoles are central reactions for synthesizing pharmaceuticals and fine chemicals. Despite tremendous progress in heterogeneous catalysis, the synthesis of these nitrogen‐containing compounds still remains challenging. Here, we report an efficient, simple, and cost‐effective nitrogen‐doped CeO2‐supported Co single‐atom catalyst (SAC) (Co/N‐CeO2) enabled synthesis of acetamides, benzimidazoles, and benzothiazoles. As far as we know, this is the first to report that SACs catalyze the synthesis of acetamides, benzimidazoles, and benzothiazoles. Detailed spectroscopic characterization revealed the structure of catalytic center. Harnessing the catalytic activity of SACs, the work offers promising routes for future synthesis of heterocycles. [ABSTRACT FROM AUTHOR]

Defects in the DNA mismatch repair (MMR) pathway can predispose individuals to colorectal cancer (CRC), with germline mutations in this pathway leading to Lynch syndrome. Consequently, universal MMR testing is recommended for all newly diagnosed CRC patients to detect mismatch repair deficient (MMR-D) tumors, enabling informed treatment decisions. Given the increased potential for metachronous disease in patients with Lynch syndrome, the current guidelines for surgical management of Lynch-associated colon cancer recommend extended resection in patients under age 60. A retrospective analysis of nonmetastatic CRC was performed from the National Cancer Database to evaluate the current trends and practice patterns in the surgical management of MMR-D colon cancer, as well as assess the factors influencing choice of surgical procedure. From 2018 to 2020, 98,112 nonmetastatic CRC patients were identified, with 19.93% being MMR-D. MMR-D colon cancer patients were more likely to undergo extended resection than those with mismatch repair proficient tumors (9.4% versus 4.2%, P < 0.001). When accounting for approximately one-fourth of MMR-D colon cancers being attributable to Lynch syndrome, the frequency of extended resection was less than expected (9.4% versus 25%, P < 0.001). MMR-D patients under age 60 were more likely to undergo extended resection than those over age 60 (9% versus 3%) (odds ratio [OR] 3.57, 95% confidence interval [CI] 3.06-4.15). Several factors were associated with decreased rate of extended resection: uninsured (OR 0.42, 95% CI 0.21-0.84), Black race (OR 0.54, 95% CI 0.35-0.82), treatment at nonacademic centers (OR 0.74, 95% CI 0.56-0.97), and crowfly distance >25 miles (OR 1.98, 95% CI 1.14-3.45). These findings provide valuable insight into the current surgical practice patterns in the management of MMR-D colon cancers and possibly colon cancers associated with Lynch syndrome. [ABSTRACT FROM AUTHOR]

In this work, an efficient, green and retrievable heterogeneous chitosan-supported antimony trichloride catalyst (SbCl3@Chitosan) was synthesized by dispersing antimony trichloride on amine functionalized chitosan modified with methyl salicylate and characterized by using Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Powder X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and ICP-AES analysis. FTIR indicated the various functionalities present in the catalyst such as 3299–3367 cm−1 (N–H and O–H), 2924 and 2874 cm−1 (C–H), 1424 cm−1 (CH2), 1376 cm−1 (CH3), 1151 cm−1 (C–O–C), 1059 and 1020 cm−1 (C–O of chitosan), 1559 cm−1 (C–N), 1653 cm−1 (C = O stretching of amide), 1302 and 1376 cm−1 (Sb–Cl). TGA showed that the catalyst was stable upto 200 °C thereby determining its thermal stability. The characteristic peaks appeared in the powder XRD of the catalyst confirmed the crystal face of antimony. The surface morphology of the catalyst revealed through SEM images exhibited a uniform distribution, and the majority of particles displayed a near-spherical morphology. ICP-AES analysis data revealed the overall content of antimony present in the synthesized catalyst. The catalytic activity of the catalyst was evaluated for the synthesis of 1,2,4,5-tetrasubstituted imidazoles under green reaction conditions. The present method for the synthesis of tetrasubstituted imidazoles has broader significance due to synthesis of various imidazole derivatives in high to excellent yields (83–95%) with short reaction times and high purity under solvent-free conditions with a simple work-up procedure. Moreover, the aforementioned catalyst (SbCl3@Chitosan) could be easily separated from the reaction mixture and reused for five runs without any decline in its catalytic activity. [ABSTRACT FROM AUTHOR]

A series of novel 2,4,5‐trisubstituted imidazole motifs have been synthesized by a magnetically‐tuned halloysite‐supported sulfonic acid catalyst. The prepared supported sulfonic acid catalyst was well characterized by High‐resolution transmission electron microscopy (HR‐TEM), Scanning electron microscopy (SEM), Energy dispersive X‐rays spectroscopy (EDS), Fourier transform infrared (FTIR), X‐ray powder diffraction (XRD), Thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET), and Vibrating–sample magnetometry (VSM) techniques; and compounds were confirmed by 1H, 13C‐Nuclear magnetic resonance (NMR) and High resolution mass spectrometry (HRMS) techniques. The purity of compounds was established by High performance liquid chromatography (HPLC). All the prepared compounds were screened for their in vitro antidiabetic activity by using α‐amylase and α‐glucosidase inhibition assay taking acarbose as a reference standard and were found to exhibit significant α‐amylase inhibitory potentials, whereas for α‐glucosidase inhibition, compounds were equipotent to the reference standard. Compound bearing ferrocene moiety was identified as the strongest α‐amylase inhibitor of the series with IC50=47.83±0.63 μM, a five‐fold more potency compared to acarbose (IC50 =269.39±0.29 μM). The presence of substituents in the second position of imidazole pharmacophore plays a key role in inhibitory activity. To find the possible binding interaction of compounds, in silico molecular docking study was performed. [ABSTRACT FROM AUTHOR]

Halloysite nanotubes (HNTs) have emerged as one of the promising clay minerals that have myriad applications due to their unique properties. The presence of silica and alumina groups on the outer and inner surfaces allows surface modifications with different functional compounds. Depending on the applications required, numerous desired compounds have been used for both inner and outer surface modifications to construct hybrid noanostructures which further enhance their physiochemical properties. This review discusses the surface design with special emphasis on magnetic nanoparticles to fabricate HNT-based magnetic nanostructures which display synergistic effects and summarizes potential applications in the fields of catalysis, magnetically driven drug delivery, chemotherapy/diagnosis, environmental remediation, emulsification, and microwave absorption. [ABSTRACT FROM AUTHOR]

Single-atom catalysts (SACs) have developed as a potential advanced variety of catalysts wherein copper SACs (Cu SACs) have appeared as a rising star in catalysis in which promising catalytic activity is achieved by a well-adjusted d-band center. Herein, the most recent advancements in the synthesis of copper SACs are highlighted. Various electrocatalytic applications such as carbon dioxide reduction reaction, oxygen reduction reaction, nitrogen reduction reaction, biotherapeutic applications, coupling reactions, hydroxylation, hydrogenation, photocatalytic reactions, and other miscellaneous reactions of Cu SACs coordinated into different supports have been thoroughly reviewed, and the stability and electrocatalytic performance of Cu SACs in fuel cells, zinc–CO2 batteries, and zinc–air batteries have been discussed. This review summarizes the study of most recent developments in the synthesis and applications of Cu SACs. [ABSTRACT FROM AUTHOR]

There has been growing interest towards clay minerals such as halloysite nanotubes (HNTs) due to their biocompatibility, availability and potential applications in the field of catalysis. Halloysite nanotubes can be modified on both the surfaces to tune their properties explicitly for their innumerable applications in the field of catalysis. The outer surface of halloysite nanotubes is fit for functionalization to develop halloysite catalysts, which creates a valuable provision for endorsing catalytic applications with tunable properties. Furthermore, the occurrence of an empty lumen unlocks new perspectives for the creation of nanostructures with synergistic catalytic effects. This class of compounds displayed promising catalytic performances, and up to now, halloysite-based catalysts have been useful for promoting several chemical transformations. Taking into account the excellent catalytic performance of these nanotubes as catalysts or catalyst supports, the main focus of this review article is to unveil the research on halloysite nanotubes for the preparation of solid acids and their applications in acid catalytic processes. [ABSTRACT FROM AUTHOR]

Despite of very valuable endowments and efforts, overall survival rates of cancer patients have changed little. To bring cancer under control is a much more impregnable and challenging job as cancer causing agents can be present in food, water, and air. Cancer is a major public health problem in USA and many other parts of the world. The present review abridges synthetic avenues to some Food and Drug Administration-approved anticancer drugs. [ABSTRACT FROM AUTHOR]

Amorphous carbon-silica composites bearing sulfonic acid derived from inexpensive natural organic compounds (glucose, maltose, cellulose, chitosan and starch) were prepared by partial carbonization followed by sulfonation and their catalytic activity was evaluated for the protection of aldehydes as 1,1-diacetates and for N-, O- and S-acylations under solvent-free conditions. Different biomaterials have been chosen, with a view to select the most active solid acid catalyst. Carbon-silica composites were characterized by FTIR, XRD and elemental analysis. Sulfonated carbon-silica composite derived from starch was found to be the most active and could be recycled for several runs without loss of significant activity. It was also characterized by TGA, SEM and TEM. [ABSTRACT FROM AUTHOR]

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Review: 259 refs. [ABSTRACT FROM AUTHOR]

Virus, a sub-microscopic infectious agent that replicates only inside the living cells of a host, causes viral infection. Currently, the immediate imperative is to control the combat against novel coronavirus outbreak caused by the COVID-19 virus, which started in China and spread all over the world. The domain of travelling has emphasized COVID-19 virus prevention as a serious issue for the safety of human beings. The exponential rise in the number of corona patients is a matter of concern for governing bodies of various countries in spite of countless cooperative efforts put in by citizens, organizations and government. India is now among the top worst hit nation in terms of the spread of COVID-19 pandemic. The present article reviews various state-of-art medicinal approaches available that are presently used to control the spread of coronavirus pandemic., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)