Enthalpies of Combustion and Formation of Histidine Stereoisomers

Table 6

Ideal gas state enthalpies of formation of isomeric histidines.

Isomeric histidines	(kJ·mol^−1) [18–20]	(kJ·mol^−1) [21]	(kJ·mol^−1)^a	(kJ·mol^−1)^b	(kJ·mol^−1) (calculated)^c
L-histidine	148 ± 10	182	304 ± 14	270	284.60
D-histidine	148 ± 10	182	301 ± 14	267
DL-histidine	148 ± 10	182	304 ± 14	270

^aCalculated with enthalpy of sublimation from column 2. ^bCalculated with enthalpy of sublimation from column 3. ^cEstimated value by means of the group additivity method, with parameters recommended by Domalski and Hearing [14].