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 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...

Spectrophotometric micro determination of allopurinol (ALP) via charge-transfer formation is described. This includes the utility of some π-acceptors such as 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) and 3,6-dichloro-2,5-dihydroxy-p-benzoquinone (p-CLA) for estimation of ALP drug (act as è-donor). These reactions are applied for determination of ALP in its pharmaceutical preparations coming...

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 charge-transfer (CT) complexes of some N-arylcarbamates as donors with a number of 7r-acceptors have been studied spectrophotometrically. The Lewis basicities of the N-arylcarbamates as well as the types of interactions are discussed. The 'H-NMR spectra of some CT complexes with both 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) indicate a decrease o...

The charge-transfer (CT)-crystal naphthalene (N)-1,2,4,5-tetracyanobenzene (TCNB) was doped with various guest acceptors. CT-complexes of these acceptors with N are formed acting as a triplet energy trap in the crystal. This provides a method to investigate oriented CT-complexes ESR-spectroscopically. In favorable cases the hyperfine structure (Hfs) in the ESR-spectra can be resolved and interp...

Charge-transfer (CT) π-complexes are formed between planar porphyrins and 1,4,5,8,9,12-hexaazatriphenylene (HAT) derivatives with large formation constants (e.g., 104 M-1), exhibiting broad CT absorption bands. The unusually large formation constants result from close face-to-face contact between two planar π-planes of porphyrins and HAT derivatives. The redox potentials of porphyrins and HAT d...

Investigation of charge-transfer (CT) complexes of drugs has been recognized as an important phenomenon in understanding of the drug-receptor binding mechanism. Structural, thermal, morphological and biological behavior of CT complexes formed between drug quinidine (Qui) as a donor and quinol (QL), picric acid (PA) or dichlorodicyanobenzoquinone (DDQ) as acceptors were reported. The newly synth...

ABSTRACT. The solid charge transfer (CT) complexes of fluorescein (Flu) with definite acceptors (tetrafluoro para benzoquinone (Fla); 7,7,8,8-tetracyanoquinodimethane (TCNQ); 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) and iodine) were prepared. Several characteristic analytic procedures such as transmission (FT-IR), diffuse reflectance, UV-Vis absorption, cyclic voltammetry used to determine...

Asymmetric charge transfer (CT) spectra from combinations of carbazole derivatives and chloranil are shown to consist of two bands originating from the highest (HOMO) and second highest (HOMO 2) energy occupied molecular orbitals of carbazole. Symmetry arguments are used to indicate tha t of two possible (parallel plane) alignments of donor and acceptor, t h a t which is totally symmetric gives...