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Aptamers are chemical antibodies possessing the capability of overcoming the limitations posed by conventional antibodies, particularly for diagnostic, therapeutic, and theranostic applications in cancer. The ease of chemical modifications or functionalization, including conjugations with nucleic acids, drug molecules, and nanoparticles, has made these aptamers to gain priorities in research. In this Mini-review, various reports on therapeutics with aptamer-functionalized nanomaterials for controlled or multistep drug release, targeted delivery, stimuli-responsive drug release, etc. are discussed. In the case of nucleic-acid-conjugated aptamers, DNA nanotrains and DNA beacons are discussed in terms of the possibility of multidrug loading for chemotherapy and gene therapy. Developments with electrochemical aptasensors and signal-enhanced immune aptasensors are also discussed. Further, the future scope of aptamer technology in cancer theranostics and the prevailing limitations are discussed., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Heterocyclic moieties play a significant role in the field of drug discovery. C-N and C-O bond formation reactions are the primary synthetic sequence for the generation of heterocyclic molecules. The generation of C-N and C-O bonds involves the use of mostly Pd or Cu catalysts although other transition metal catalyst's are also involved. However, in C-N and C-O bond formation reactions, several problems were faced such as catalytic systems containing costly ligands, lack of substrate scope, lots of waste generation, and high temperature conditions. So it is imperative to uncover new eco-friendly synthetic strategies. In view of enormous drawbacks, it is important to develop an alternate microwave-assisted synthesis of heterocycles via C-N and C-O bond formation, which provides a short reaction time, tolerance for functional groups, and less waste production. Numerous chemical reactions have been accelerated using microwave irradiation which provides a cleaner reaction profile, lower energy consumption, and higher yields. This review article highlights a comprehensive overview on the potential application of microwave assisted synthetic routes for the synthesis of diverse heterocycles via mechanistic pathways covering the year ranges from 2014 to 2023, along with possible biological interests., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

The aim of the presented work involves the isolation, characterization, and evaluation of hepatoprotective potential of Clerodendrum paniculatum flower extracts. For this purpose, petroleum ether, chloroform, ethyl acetate, alcohol, and water extracts of C. paniculatum flower were screened for the flavonoid and phenolic content and quantified. Various antioxidant activity assays including 2,2'-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO) radical scavenging, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and reducing ability were carried out. Of the above methods, the alcoholic extract exhibited high antioxidant potential and was selected further for the hepatoprotective evaluations. Hepatoprotective evaluation of the alcoholic extract was carried out for carbon tetrachloride (CCl 4 )-intoxicated model systems. Enzymes associated with liver functions were estimated, and histopathological evaluations were carried out to monitor the liver architecture. Prominently, reduced levels of various associated enzymes along with increased protein content were observed when the liver specimen was pretreated with the extract. Moreover, the liver architecture was almost comparable to that of the normal control group. The column chromatographic analysis of the extract revealed 13 fractions to possess high phenolics and flavonoid contents. The best two fractions were identified for in vitro hepatoprotective evaluation in the goat liver model. Furthermore, the GC-MS analyses of the fractions were carried out followed by a library search, to identify the constituents responsible for the hepatoprotective activity which revealed the presence of four major constituents-pilocarpine, glyceric acid, pangamic acid, and gallic acid. An in vitro hepatoprotective study of the isolated fractions showed better activity compared to the whole alcoholic extract, and the results were comparable to the normal group taken as a control. The investigations with an in vitro model suggest that the isolated fraction with rich flavonoid content showed better hepatoprotective activity. GC-MS analysis of the fractions that displayed good hepatoprotective activity suggested the presence of pilocarpine, glyceric acid, pangamic acid, and gallic acid, while HPTLC analysis revealed the presence of quercetin., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

The emergence of more virulent SARS virus has made scientists look back at other so-called neglected diseases such as dengue, Zika, and chikungunya, etc. Until recently these neglected diseases have not received much attention for their control or elimination from society. Over the past decade several attempts to investigate the pathogenicity, diagnostic, and therapeutic strategies for flavivirus caused diseases have been made. Herein we have reviewed the progress made toward the detection and treatment of two diseases-dengue and Zika. The above flavivirus related pathogenesis is concerned with the host immune system and known to be mediated through various receptors along with antibody-mediated disease enhancement. Moreover, researchers have been progressing toward discovering new drugs and therapeutic methods that target various stages of the flavivirus life cycle to minimize the above caused mortality and morbidity. The available diagnostics are based on serological, small molecule detection systems and point-of-care sensing devices. In this work, we have reviewed the advancements made toward understanding the pathogenesis, diagnostics, and therapeutics of the viral diseases caused by dengue and Zika., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

In this study, a highly efficient two-component [3 + 2] cycloaddition reaction of substituted aryl aldehydes with 4-toluenesulfonylmethyl isocyanide (TosMIC) in the presence of 2 equiv of potassium phosphate as a base to 5-substituted oxazoles were established in a isopropanol medium under microwave irradiation. However, using 1 equiv of K 3 PO 4 as a base resulted in the diastereoselective synthesis of 4,5-disubstituted oxazolines under identical reaction conditions. The foremost benefits of these protocols are the moderate-to-excellent yields with good functional group compatibility, simple experimental procedure, inexpensive readily available starting materials, nonchromatographic purification, and high bond-forming efficiency. The synthetic manipulation reported herein represents a cleaner route to the sustainable preparation of 5-substituted oxazoles and diastereoselective 4,5-disubstituted oxazolines derivatives., Competing Interests: The authors declare no competing financial interest., (© 2020 The Authors. Published by American Chemical Society.)

A highly efficient, clean, and simple procedure for the synthesis of a privilege imidazo[4,5- b ]pyridine scaffold from 2-chloro-3-nitropyridine in combination with environmentally benign H 2 O-IPA as a green solvent is presented. The scope of the novel method has been demonstrated through the tandem sequence of S N Ar reaction with substituted primary amines followed by the in situ nitro group reduction and subsequent heteroannulation with substituted aromatic aldehydes to obtain functionalized imidazo[4,5- b ]pyridines with only one chromatographic purification step. The synthesis pathway appears to be green, simple, and superior compared with other already reported procedures, with the high abundance of reagents and great ability in expanding the structural diversity., Competing Interests: The authors declare no competing financial interest.