Publications by authors named "Subhendu Bhowmik"

In this study, 1,4-benzothiazine-based bisamide derivatives, a new class of antibacterial agents targeting bacterial peptide deformylase (PDF), were designed and synthesized to combat infection. Molecular modeling of the designed molecules showed better docking scores compared to the natural product actinonin. Bioactivity assessment identified two derivatives with promising antibacterial activity .

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Background: Multicomponent reactions are highly useful in synthesizing natural products and bioactive molecules. Out of several MCRs, although utilized widely, some remain neglected in review articles. The Gewald and Groebke-Blackburn-Bienaymé (GBB) reactions are two such reactions.

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A one-pot, regioselective decarboxylative alkynylation of tetrahydro-β-carboline-1-carboxylic acid under peroxide-free condition is reported. The reaction is highly selective for the 1-position over the 3-position of tetrahydro-β-carboline. The reaction can afford alkynylated or enaminone products depending on the reagent.

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Hypotheses of the origins of RNA and DNA are generally centred on the prebiotic synthesis of a pristine system (pre-RNA or RNA), which gives rise to its descendent. However, a lack of specificity in the synthesis of genetic polymers would probably result in chimeric sequences; the roles and fate of such sequences are unknown. Here, we show that chimeras, exemplified by mixed threose nucleic acid (TNA)-RNA and RNA-DNA oligonucleotides, preferentially bind to, and act as templates for, homogeneous TNA, RNA and DNA ligands.

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Prebiotic phosphorylation of (pre)biological substrates under aqueous conditions is a critical step in the origins of life. Previous investigations have had limited success and/or require unique environments that are incompatible with subsequent generation of the corresponding oligomers or higher-order structures. Here, we demonstrate that diamidophosphate (DAP)-a plausible prebiotic agent produced from trimetaphosphate-efficiently (amido)phosphorylates a wide variety of (pre)biological building blocks (nucleosides/tides, amino acids and lipid precursors) under aqueous (solution/paste) conditions, without the need for a condensing agent.

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Phosphorylation under plausible prebiotic conditions continues to be one of the defining issues for the role of phosphorus in the origins of life processes. In this review, we cover the reactions of alternative forms of phosphate, specifically the nitrogenous versions of phosphate (and other forms of reduced phosphorus species) from a prebiotic, synthetic organic and biochemistry perspective. The ease with which such amidophosphates or phosphoramidate derivatives phosphorylate a wide variety of substrates suggests that alternative forms of phosphate could have played a role in overcoming the "phosphorylation in water problem".

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A general approach for the synthesis of 3H-pyrazolo[3,4-c]isoquinolines and thieno[3,2-c]isoquinolines is described involving the implementation of a cascade imination/intramolecular decarboxylative coupling between potassium 2-amino(hetero)benzoates and 2-haloarylaldehydes. The reactions of pyrazole-based substrates require a Pd-Cu bimetallic system for superior yields whereas the thienyl-based substrates afford the products in excellent yields with a Pd-catalyst only.

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A controlled cascade: A divergent, diastereoselective and efficient one-pot synthesis of allocolchicinoids via a cascade Suzuki-Michael addition-Carbocyclization sequence is described. The utility of the compounds as possible inhibitors of insulin aggregation is also presented.

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