Novel formazan derivatives containing phenylsulfanyl and carbonyl units: synthesis, optical and electrochemical properties

Abstract

New phenylsulfanyl and aryl carbonyl containing formazan derivatives 4a–4h and 5a–5h have been developed, and investigated the effect of substituents on their photophysical and electrochemical properties.

Substituent‐Dependent Absorption Spectra, Electrochemical and Antiproliferative Activity Studies of Some 3‐(4‐(Benzyloxy)phenyl)‐5‐(4‐methoxyphenyl)‐1‐(substitutedphenyl)formazans

“…Nonexistence of N À H frequency bands among 3100 and 3500 cm À 1 supports the pseudo aromatic chelate structure by an intramolecular hydrogen bonding (Ph 1 À NH ⋅⋅⋅ N À Ph 5 ) of formazans in FTIR spectra. [3][4][5]29] Observation weak bands of N À H characteristic stretching bands at 3062 and 3066 cm À 1 for compounds F2 and F4 indicates the existing of intramolecular hydrogen bonding. [3][4][5] At the same time, the sharp characteristic C=N tension vibration bands were observed around 1599 and 1600 cm À 1 for F2 and F4, respectively, pointing out the presence of chelate form.…”

“…[3][4][5]29] Observation weak bands of N À H characteristic stretching bands at 3062 and 3066 cm À 1 for compounds F2 and F4 indicates the existing of intramolecular hydrogen bonding. [3][4][5] At the same time, the sharp characteristic C=N tension vibration bands were observed around 1599 and 1600 cm À 1 for F2 and F4, respectively, pointing out the presence of chelate form. [3][4][5] The observation of intense bands at 1463 and 1454 cm À 1 of F2 and F4 indicates the À N=N À group, which is well in agreement with the reported IR values.…”

“…These compounds were prepared via the coupling of the phenylhydrazone derivatives with 4-methoxy diazonium cation in a basic medium at 0°C in moderate yields of 64 % by recrystallization in methanol. [3][4][5] Reaction conditions are important for formazan synthesis. Thus, enhancement of the reaction condition is achieved by addition of a solution of NaOH with pyridine having a characteristic of a strong catalyst which abstracts proton.…”

“…For formazan derivatives, the study of intramolecular hydrogen bonding, tautomer properties, infrared spectra, absorption spectra and the X-ray diffraction structures as well as DFT calculation were commonly reported in the literature. [1][2][3][4][5] As well, formazans bearing electron rich/deficient subunits in characteristic 1,3,5-phenyl ring were synthesized, and the effects of solvents and substituents on absorption spectra were investigated. [3][4][5][6][7] At the same time, formazan derivatives are be descript with their prominent π-π* transitions on absorption spectra which are sensitive to character substituents in the phenyl rings and nature of the solvent, compared to Schiff bases having n-π* transitions in visible region.…”

“…[1][2][3][4][5] As well, formazans bearing electron rich/deficient subunits in characteristic 1,3,5-phenyl ring were synthesized, and the effects of solvents and substituents on absorption spectra were investigated. [3][4][5][6][7] At the same time, formazan derivatives are be descript with their prominent π-π* transitions on absorption spectra which are sensitive to character substituents in the phenyl rings and nature of the solvent, compared to Schiff bases having n-π* transitions in visible region. [8][9][10][11] Moreover, formazans derivatives have fascinated the interest due to their diverse chemical reactivities and broad spectrum of biological activities such as antimicrobial, antiviral, anti-oxidant, analgesic, anti-inflammatory, anticonvulsant, antiparkinsonian, antiproliferative, anthelmintic, antitubercular, and cardiovascular.…”