Synthesis, Absorptivity and Antimicrobial Activity of Chromophoric Chain β-substituted benzothiazolo-Hemicyanine Dyes

Abstract

A number of chromophoric chain β-substituted benzothiazolo-hemicyanine

(CCSBH) dyes have been synthesized by condensing

2-methyl benzothiazolo-methiodide and 2-methyl-6-substituted

benzothiazolo-methiodides with dimethylaminobenzophenone derivatives

using piperidine as basic catalyst and ethanolic DMF as

solvent. These dyes were synthesized with a view to study the effect

of the nature of the chain-β-substituents on their absorption spectra

and to investigate their antimicrobial efficacy. The dyes were found

to show bathochromic shifts irrespective of the functional additives

whether electron donating or withdrawing but hypsochromic shifts

with respect to butadienylene chain hemicyanines. Purified samples

were also subjected to in vitro antimicrobial screening to evaluate

their bactericidal activity and halo derivatives were found to be

highly active against Staphylococcus aureus and Escherichia coli.