Jolanta Sokołowska

Synthesis and evaluation of organic pigments and intermediates. 1. Nonmutagenic benzidine analogs

Abstract The design, synthesis, characterization, and genotoxicity of 4,4′ diaminobiphenyl (benzidine) analogs with substituents in the 3,3′ and/or 2,2′ positions are reported. Analogs containing bulky substituents in the 3,3′ positions significantly reduce or eliminate mutagenic activity, while substituents in the 2,2′-positions increase the dihedral angle across the biphenyl linkage––a property that can be utilized in the design of novel nonmutagenic colorants. 2,2′-Dimethylbenzidine was found to be mutagenic in both the standard Salmonella mammalian mutagenicity assay (Ames test) with metabolic acitivation and the preincubation assay protocol. 2,2′-Dichloro-5,5′-dipropoxybenzidine, 2,2′-dimethoxy-5,5′-dipropoxybenzidine and 2,2′-dimethyl-5,5′-dipropoxybenzidine were nonmutagenic in both assays. The corresponding bis-acetoacetamido derivatives of the latter two compounds were also nonmutagenic. Good yields with minimal purification were obtained for certain diamines, providing potentially useful nongenotoxic intermediates in the synthesis of bisazo and bisazomethine dyes and pigments.

The photostability of some fluorescent disperse dyes derivatives of coumarin

The photochemical behaviour (in UV and visible light) of C.I. Disperse Yellow 232 and related heterocyclic compounds in ethanol, DMF and ethyl benzoate in the presence or absence of air was investigated. The lightfastness of the dyes on synthetic fibres was studied in relation to their photostability in the solvents.

Synthesis and evaluation of organic pigments.: 3. Studies based on nonmutagenic twisted benzidines

Abstract Bis-chromophoric pigments prepared using nonmutagenic benzidine analogs with high dihedral angle across the biphenyl linkage are reported. The mutagenic properties of twisted bisazomethine, disazoacetoacetanilide, disazopyrazolone, disazobenzimidazolone and disazonaphthol pigments were established using the standard Ames Salmonella mammalian mutagenicity assay and the Prival modification. Results from these tests and from the evaluation of hue, color strength and photostability of the pigments prepared are reported. Some of the new pigments are potential viable alternatives to those derived from 3,3′-dichlorobenzidine and other genotoxic analogs of benzidine.

Benzothiazine Dyes/2,4,6-Tris(trichloromethyl)-1,3,5-triazine as a New Visible Two-Component Photoinitiator System

Novel photoinitiator systems working under visible radiation were studied. The photoredox pair constructed with dye derivatives of 12H-quinoxalino-[2,3-b][1,4]-benzothiazine (1–3) and 2,4,6-tris(trichloromethyl)-1,3,5-triazine (Tz) were found to be effective initiators for free radical polymerization of trimethylolpropane triacrylate (TMPTA) using VIS light. Photosensitization occurred through electron transfer, which was confirmed by the observation of a radical cation of the studied dyes. The 1•