A flash photolysis and stopped-flow spectroscopy study of 3',4'-dihydroxy-7-O-β-D-glucopyranosyloxyflavylium chloride, an anthocyanin analogue exhibiting efficient photochromic properties.

The complete determination of all rate and equilibrium constants of the network of reversible chemical reactions involving the anthocyanin analogue, 3',4'-dihydroxy-7-O-β-D-glucopyranosyloxyflavylium chloride, was achieved by means of UV-visible spectroscopy, flash photolysis and pH jumps monitored by stopped-flow. An energy level diagram containing all the data was obtained. A detailed step by step procedure illustrating all the calculations is reported.