The color developing reaction between ambrisentan and 2,3-dichloro-5,6-dicyano-1,4- benzoquinone (DDQ) or 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (CLA) was successfully employed in the development of two simple and sensitive spectrophotometric methods (M1 and M2) for the determination of ambrisentan in its pharmaceutical dosage forms.The methods are based on the charge transfer reaction of ...

The interaction of the perimidone drug in solution state with the σ-acceptor iodine, the aliphatic π-acceptor tetracyanoethylene (TCNE) and the aromatic π-acceptor 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) have been studied through the initial formation of ionic intermediate to charge transfer (CT) complex in methanol at room temperature. The spectral studies of the complexes were determi...

the purpose of this investigation was directed to propose sensitive, accurate and reproducible methods of analysis that can be applied to determine distigmine bromide (dtb), cyclopentolate hydrochloride (cphc), diaveridine hydrochloride (dvhc) and tetrahydrozoline hydrochloride (thhc) drugs in pure form and pharmaceutical preparations via charge-transfer complex formation with 7,7,8,8-tetracyan...

the interaction between benzo-15-crown-5 (b15c5), dibenzo-18-crown-6 (db18c6), dibenzyl-daza-18crown-6 (dbzda18c6), n-phenyl-aza-15-crown-5 (npha15c5) and dibenzopyridine-18-crown-6 (dbpy18c6) with π-acceptor 2,3-dichloro-5,6-dicyanobenzoquinone (ddq) in chloroform solution was studied spectrophotometrically. the interaction of b15c5-ddq and db18c6-ddq caused the formation of 1:1 charge transfe...

We report on the steady-state, picosecond and femtosecond time-resolved studies of a charge and proton transfer dye 6-amino-2-(2'-hydroxyphenyl)benzoxazole (6A-HBO) and its methylated derivative 6-amino-2-(2'-methoxyphenyl)benzoxazole (6A-MBO), in different solvents. With femtosecond resolution and comparison with the photobehaviour of 6A-MBO, we demonstrate for 6A-HBO in solution, the photopro...

Photosynthesis is one of the most essential biological processes in which specialized pigment-protein complexes absorb solar photons, and with a remarkably high efficiency, guide the photo-induced excitation energy toward the reaction center to subsequently trigger its conversion to chemical energy. In this work, we review the principles of optimal energy transfer in various natural and artific...

the complex formation reaction between iodine with tetrabutylammonium halides (tbax) has been studied spectrophotometrically in chloroform solution at 25ºc. various aspects of the spectra of iodine in the presence of various concentration of different tetrabutylammonium halides have been discussed in terms of electronic specifications of iodine and halides. in the case of tetrabutylammonium iod...

1. Electrocatalysis: This is one of the direct examples of the homogeneous reaction diffusion regime. This involves multiple steps, i.e. diffusion, adsorption and a possible charge transfer at the surface (x = 0). As shown in the schematic of Fig(1), species will adsorb on the catalyst surface, then diffuse along the surface to the right/left surfaces where a charge transfer reaction can occur....