Hetarylazopyrazolone Dyes Based on Benzothiazole and Benzimidazole Ring Systems: Synthesis, Spectroscopic Investigation, and Computational Study

Table 5

Absorption maxima of dyes in acidic and basic solutions.

Dye number	Methanol			CHCl3			DMF		DMSO
3a	457	440	459	418	418	469	469	469	469	469
3b	462	440	463	422	420	469	469	469	469	469
3c	467	479	466	450	452	469	469	469	472	472
3d	465	477	465	450	449	469	469	469	469	469
3e	, 442	453	, 442	452	451	457	457	457	461	461
3f	460	462	449	464	464	464	462	462	469	469

TFAA: trifluoroacetic acid.
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