Visible Spectrophotometric Methods for Estimation of Zopiclone from Bulk Drug and Formulation

Abstract

Two simple extractive colorimetric methods for estimation
of zopiclone, 6-(5-chloro-2-pyridyl)-6,7-dihydro-7-oxo-5H-pyrrolo-
[3,4-b ]-pyrazin-5-yl-4-methyl piperazine-1-carboxylate, a
non- benwdiazepine derivative which is mainly used as a hypnotic
for short term management of insomnia, have been developed.
The developed methods involve formation of coloured chloroform
extractable complexes of drug wth bromocresol purple and
bromocresol green in neutral and acidic medium. Extracted
complexes showed absorption maxima at 410 om and 420 nm
respectively. Results were validated statistically and were found to
be reproducible.