OBJECTIVES Aminocoumarin antibiotics are potent inhibitors of bacterial DNA gyrase. We investigated the inhibitory and antibacterial activity of naturally occurring aminocoumarin antibiotics and six structural analogues (novclobiocins) against DNA gyrase and DNA topoisomerase IV from Escherichia coli and Staphylococcus aureus as well as the effect of potassium and sodium glutamate on the activi...

We present a hybrid Time-Dependent Density Functional /Molecular Mechanics (TDDFT/MM) simulation study on the optical properties of aminocoumarins in gas phase and solution. As solvation is described through a molecular approach, the effects due to the inhomogeneities of the electric field of the solvent molecules are fully included. We focus on the ground state and first excited singlet state ...

a Biochemistry and Molecular Biology Division, Department of Biology, University of Isfahan, Iran b Biomimetic Materials and Tissue Engineering Laboratories, Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208, USA c Faculty of Pharmacy, Medical University of Sofia, Bulgaria d Department of Toxicology, Faculty of Pharmacy, University of Belgrade, Serbia e Depart...

A novel and metal-free procedure has been developed for the construction of 3-sulfonated coumarins via the direct difunctionalization of alkynoates with sulfonylhydrazides. The present protocol, which simply utilizes TBAI as the catalyst and TBHP as the oxidant, provides a convenient and highly efficient approach to construct a series of sulfonated coumarins with high regioselectivity and good ...

A series of pentacyclic heterocyclic systems (15 examples, 69-89%) have been synthesized using intramolecular Povarov reactions involving 3-aminocoumarins and O-cinnamylsalicylaldehydes. The Povarov adducts are formed with high selectivity for the trans,trans relative stereochemistry in the newly-formed [6,6] fused ring system. One example of a Povarov adduct featuring a new [6,5] fused ring sy...

The biosynthesis of aminocoumarin antibiotics involves the action of amide synthetases which construct amide bonds between aminocoumarins and various acyl moieties. Libraries of aminocoumarin analogues have been generated by in vivo fermentation, via feeding known amide synthetase substrates into producing microbial strains. Critically, such feeding studies rely on the inherent or engineered su...

Natural products, many of which are decorated with essential sugar residues, continue to serve as a key platform for drug development. Adding or changing sugars attached to such natural products can improve the parent compound's pharmacological properties, specificity at multiple levels, and/or even the molecular mechanism of action. Though some natural-product glycosyltransferases (GTs) are su...