Studies on Some Thiazolylazo Compounds and Their Cobalt, Nickel, and Copper Complexes

Investigation of ground state tautomeric form of a heterocyclic disazo dye derived from barbituric acid by ab initio Hartree–Fock and density functional theory calculations

“…Therefore, several studies have been published on the synthesis and spectral properties of several azo barbituric acids, as well as on their transition metal complexes, [1][2][3][4][5][6][7]. The novel heterocyclic disazo dyes can be derived by diazotizing and coupling of 5-amino-4-arylazo-3-methyl-1H-pyrazole with barbituric acid.…”

1-naphthylazo derivatives of some 1,3-dicarbonyl compounds and their Cu (II), Ni(II) and Zn(II) complexes

“…1 These arylazo derivatives have gained considerable importance in recent years because of their application in the laboratory as acid-base, redox, metallochromic and other indicators, 2-4 as stains for bacteriological and histological investigations, [3][4][5][6] in the study of acid-base equilibrium and acidity constant values 3,7 and in the preparation of a large number of biologically important heterocyclic compounds. 8 Many variations in the dicarbonyls as well as the diazonium salt have been studied in attempts to improve the colour, solubility and stability of the resulting dyes.…”

Synthesis, Characterization, Absorption and Fastness Properties of Novel Monoazo Dyes Derived from 1-Phenyl-3-amino-4-(2-thiazolilazo)pyrazol-5-one

“…Among these azo dyes, heterocyclic moieties, e.g., pyrazolone, indole, pyrimidine, imidazole, pyridone, quinolone, coumarin, etc., provide higher tinctorial strength and brighter texture as compared to dyes based on phenylic components. [1][2][3][4][5] Hetarylazo dyes based on heterocyclic diazo and coupling components have been attracted the attention of scientists in recent years. [6][7][8][9][10][11][12] Among these, the hetarylazopyrazolone dyes have high fluorescence, high quantum yield, superior photostability in the visible region, excellent fastness properties, [13][14][15][16] tautomeric structures 6,7,10,17 in addition to their bathochromic effects in the absorption spectra.…”