Kinetics and mechanism of oxidation of glutathione (reduced) (γ-L-glutamyl-L-cysteinylglycine) by pyridinium chlorochromate in acid medium

The electron transfer reaction between glutathione (reduced) (GSH) and pyridinium chlorochromate (PCC) has been studied spectrophotometrically over the range 3.00 <= 10(3)[GSH] <= 6.00 mol dm(-3), 0.01 <= [H+] <= 0.03 mol dm(-3) and 293 <= T <= 313 K. The rate of reaction is found to increase with the increase in [GSH](T) and [H+](T). The reaction is found to exhibit first order dependence in [GSH](T), [H+](T) and [PCC](T). The Delta H-not equal (kJ mol(-1)) and Delta S-not equal (JK(-1) mol(-1)) for the electron transfer reaction are found to be 5.90 and -177.00. The product of the reaction was found to be GSSG [((28)-2-amino-5-[[(2R)-3-[(2R)-2-[[(4S)-4-amino-5-hydroxy-5-oxopentanoyl]amino]-3-(carboxymethylamino)-3-oxopropyl]disulfanyl-1-(carboxymethylamino)-1-oxopropan-2-yl]amino]-5-oxopentanoic acid].