To increase the targeting potential, circulation time, and the flexibility of surface-attached biomedically-relevant ligands on gold nanoparticles, hetero-bifunctional poly(ethylene glycol) (PEG, MW 1,500) was synthesized having a thiol group on one terminus and a reactive functional group on the other. Coumarin, a model fluorescent dye, was conjugated to the PEG spacer and gold nanoparticles w...

The 'guaco' lianous herb Mikania laevigata, which is widespread in Southern Brazil, is traditionally used to treat bronchitis, asthma and cough. This work investigates the influence of the extraction method, solvent:drug ratio, ethanol proportion, harvest season (summer or winter) and solvent heating on the physicochemical profile of the extracts (dry weight, density, pH) and the coumarin (1,2-...

The effect of three aromatic amines namely aniline (AN), dimethyl aniline (DMAN) and diethyl aniline (DEAN) on emission properties of a coumarin derivative 6-methyl-3azidoacetyl coumarin (6M3AAC) in acetonitrile was studied by means of steady state fluorescence spectroscopy. The quenching of fluorescence intensity was observed in the presence of amines. The quenching process was characterized b...

The immobilization of some coumarin derivatives on modified poly(ethylene glycol)s is reported and the influence of the polymeric support on the photoluminescence activity of the compounds is discussed. Upon ultraviolet excitation, the derivatives showed coumarin-related emission properties whose peak position and efficiency depended on the loading of the polymer and on the mesomeric effects of...

We have synthesized and evaluated two self-immobilizing, turn-on fluorescent probes carrying a coumarin molecular framework for imaging intracellular human steroid sulfatase (STS) activity. The 8-fluoromethyl coumarin derivative, which gives stronger fluorescence response in the incubation study with STS preparations, was successfully applied to visualize STS activity in cells.

The methanol extract of the dried aerial parts of Prangos tschimganica gave three new coumarin derivatives and 30 known coumarin derivatives. Their structures were established on the basis of chemical and spectroscopic evidence. Absolute configuration of the isolated compounds were determined by using a modified Mosher's method. Some of the isolated compounds showed anti-HIV activity.

The present article describes the evaluation of the in vitro activity against M. tuberculosis H37Rv of eight coumarin-derived aminoalcohols and amidoamines. Seven of the compounds display activity between 10 and 20 times higher than the classicall anti-TB drug ethambutol. The combination of coumarin scaffold with aminoalcohol fragments gave the most promising activities with MICs up to 0.32 μM.

During the last 2 decades, the study of the biological activities of Coumarin derivatives has been the aim of many researchers. Based on these findings, a series of Coumarin substituted benzothiazoles were synthesized by refluxing Coumarin-4-carboxaldehyde and oaminothiophenol in acetic acid. Compounds were characterized by IR, 1H NMR and mass spectroscopy. All the compounds were tested for the...

The present study evaluated the antioxidant potential of 28 coumarin derivatives, using three antioxidant assays: DPPH inhibition, total reducing power and NO inhibition. Out of the tested compounds, the most active DPPH free radicals scavengers were the coumarin hydrazide derivatives. These substances were also the only ones among the investigated derivatives that exhibited a moderate reducing...

The effect of three aromatic amines namely aniline (AN), dimethyl aniline (DMAN) and diethyl aniline (DEAN) on emission properties of a coumarin derivative 6-methyl-3azidoacetyl coumarin (6M3AAC) in acetonitrile was studied by means of steady state fluorescence spectroscopy. The quenching of fluorescence intensity was observed in the presence of amines. The quenching process was characterized b...