Combinatorial approach towards synthesis of 2',3'-dideoxynucleosides and enzyme-catalysed selective hydrolysis of diethyl acetamidomalonate and amides of polyacetoxy aromatic carboxylic acid

507-51

Aldehydes: magnificent acyl equivalents for direct acylation

From the viewpoint of meeting the current green chemistry challenges in chemical synthesis, there is a need to disseminate how the cocktail of acylation and activation can play a pivotal role in affording bioactive acylated products comprising substituted ketone motifs in fewer reaction steps, with higher atom-economy and improved selectivity. In recent years, a significant number of articles employing the title compounds “aldehydes” as magnificent acylation surrogates which are less toxic and widely applicable have been published. This review sheds light on the compounds use for selective acylation of arene, heteroarene and alkyl (sp3, sp2 and sp) C–H bonds by proficient utilization of the C–H activation strategy. Critical insights into selective acylation of diverse moieties for the synthesis of bioactive compounds are presented in this review that will enable academic and industrial researchers to understand the mechanistic aspects involved and fruitfully employ these strategies in designing novel molecules

Biodegradable PEG-PCL Nanoparticles for Co-delivery of MUC1 Inhibitor and Doxorubicin for the Confinement of Triple-Negative Breast Cancer

Combating triple-negative breast cancer (TNBC) is still a problem, despite the development of numerous drug delivery approaches. Mucin1 (MUC1), a glycoprotein linked to chemo-resistance and progressive malignancy, is unregulated in TNBC. GO-201, a MUC1 peptide inhibitor that impairs MUC1 activity, promotes necrotic cell death by binding to the MUC1-C unit. The current study deals with the synthesis and development of a novel nano-formulation (DM-PEG-PCL NPs) comprising of polyethylene glycol-polycaprolactone (PEG-PCL) polymer loaded with MUC1 inhibitor and an effective anticancer drug, doxorubicin (DOX). The DOX and MUC1 loaded nanoparticles were fully characterized, and their different physicochemical properties, viz. size, shape, surface charge, entrapment efficiencies, release behavior, etc., were determined. With IC(50) values of 5.8 and 2.4 nm on breast cancer cell lines, accordingly, and a combination index (CI) of < 1.0, DM-PEG-PCL NPs displayed enhanced toxicity towards breast cancer cells (MCF-7 and MDA-MB-231) than DOX-PEG-PCL and MUC1i-PEG-PCL nanoparticles. Fluorescence microscopy analysis revealed DOX localization in the nucleus and MUC1 inhibitor in the mitochondria. Further, DM-PEG-PCL NPs treated breast cancer cells showed increased mitochondrial damage with enhancement in caspase-3 expression and reduction in Bcl-2 expression.In vivo evaluation using Ehrlich Ascites Carcinoma bearing mice explicitly stated that DM-PEG-PCL NPs therapy minimized tumor growth relative to control treatment. Further, acute toxicity studies did not reveal any adverse effects on organs and their functions, as no mortalities were observed. The current research reports for the first time the synergistic approach of combination entrapment of a clinical chemotherapeutic (DOX) and an anticancer peptide (MUC1 inhibitor) encased in a diblock PEG-PCL copolymer. Incorporating both DOX and MUC1 inhibitors in PEG-PCL NPs in the designed nanoformulation has provided chances and insights for treating triple-negative breast tumors. Our controlled delivery technology is biodegradable, non-toxic, and anti-multidrug-resistant. In addition, this tailored smart nanoformulation has been particularly effective in the therapy of triple-negative breast cancer. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10924-022-02654-4

Antioxidant, antiinflammatory and antiinvasive activities of biopolyphenolics

A large number of polyphenolic and heterocyclic compounds, i.e. 4-methylcoumarins, 4-methylthionocoumarins, xanthones, pyrazoles, pyrazolylacrylonitriles, flavones and isoflavones have been tested for their antioxidant activity towards NADPH-catalysed liver-microsomal lipid peroxidation with a view to establish their structure-activity relationship. Inhibition of microsomal lipid peroxidation by 7,8-dihydroxy-4-methylcoumarin (DHMC, 2) and 7,8-diacetoxy-4-methylcoumarin (DAMC, 3) was intriguing. We also found that dihydroxy and diacetoxy derivatives of 4-methylthionocoumarin were more potent in comparison to the corresponding coumarin derivatives in inhibiting TNF-α induced expression of ICAM-1. The effect of nine different xanthones has been examined on the modulation of cytokine-induced expression of ICAM-1 in human endothelial cells. 1,4-Dihydroxyxanthone (10) showed enhanced antioxidant activity as well as the inhibition of the expression of cell adhesion molecules, such as ICAM-1, VCAM-1 and E-selectin on endothelial cells in a concentration and time dependent manner. Antioxidant activity of different pyrazoles and pyrazolylacrylonitriles and antiinvasive activity of flavones and isoflavones against solid tumors have also been studied

Synthesis of macromolecular systems via lipase catalyzed biocatalytic reactions: applications and future perspectives

Enzymes, being remarkable catalysts, are capable of accepting a wide range of complex molecules as substrates and catalyze a variety of reactions with a high degree of chemo-, stereo- and regioselectivity in most of the reactions. Biocatalysis can be used in both simple and complex chemical transformations without the need for tedious protection and deprotection chemistry that is very common in traditional organic synthesis. This current review highlights the applicability of one class of biocatalysts viz. ‘‘lipases’’ in synthetic transformations, the resolution of pharmaceutically important small molecules including polyphenols, amides, nucleosides and their precursors, the development of macromolecular systems (and their applications as drug/gene carriers), flame retardants, polymeric antioxidants and nanocrystalline solar cells, etc

Synthetic and mass spectral fragmentation studies on trisubstituted 2H-pyran- 2-ones and comparative EIMS behaviour of biologically active 3,5- disubstituted pyrazoles and isoxazoles

872-87

Chemoenzymatic synthesis, nanotization and anti- aspergillus activity of optically enriched fluconazole analogues

Despite recent advances in diagnostic and therapeutic advances in antifungal research, aspergillosis still remains a leading cause of morbidity and mortality. One strategy to address this problem is to enhance the activity spectrum of known antifungals, and we now report the first successful application of Candida antarctica lipase (CAL) for the preparation of optically enriched fluconazole analogs. Anti-Aspergillus activity was observed for an optically enriched derivative, (-)-S-2-(2’ ,4’ -difluorophenyl)-1-hexyl-amino-3-(1‴,2‴,4‴) triazol-1‴-yl-propan-2-ol, which exhibits MIC values of 15.6 μg/mL and 7.8 μg/disc in microbroth dilution and disc diffusion assays, respectively. This compound is tolerated by mammalian erythrocytes and cell lines (A549 and U87) at concentrations of up to 1000 μg/mL. When incorporated into dextran nanoparticles, the novel, optically enriched fluconazole analog exhibited improved antifungal activity against Aspergillus fumigatus (MIC = 1.63 μg/mL). These results not only demonstrate the ability of biocatalytic approaches to yield novel, optically enriched fluconazole derivatives but also suggest that enantiomerically pure fluconazole derivatives, and their nanotised counterparts, exhibiting anti-Aspergillus activity may have reduced toxicity

Novel Constituents of Gardenia Species — A Review

893-903The secondary metabolites from Gardenia species for the period 1907 to December 1999 have been reviewed. One hundred fifteen chemical constituents belonging to different classes of bioactive compounds e.g. flavonoids, iridoids, terpenoids, steroids, acids, esters, alcohols, etc. have been reported from different Gardenia species. A number of these compounds have been found to possess potent biological activities, i. e. anti-invasive, antiviral, anti-inflammatory, antifungal, estrogenic, neurosurgical, etc.</i