Experimental and theoretical study of racemization, stability and tautomerism of vitamin C stereoisomers

Stability, racemization and isomerization of RS-stereoisomers of ascorbic acids (AA) were investigated experimentally (specific rotation, FT-IR and 1H NMR) and theoretically (at B3LYP/6-311++G(d,p) and MP2/6-311++G(d,p) levels of theory). The activity of VC was reduced about 25% in less than 24 h at 80-90 °C.