ISSN:
1572-8927
Keywords:
Enthalpies of solution
;
thymine
;
uracil
;
nucleic acid bases
;
calorimetry
;
water
;
dimethylsulfoxide
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Enthalpies of solution of thymine and uracil in water and in dimethylsulfoxide (DMSO) were measured calorimetrically in the temperature range 25–40°C. ΔH s o at 25°C for thymine and uracil in water were found to be 23.1±0.5 and 29.5±0.3 kJ-mol−1, respectively. In DMSO, ΔH s o were 7.9±0.1 and 10.2±0.1 kJ-mol−1, respectively. In aqueous solution ΔC p o for the two nucleic acid bases were relatively large and positive with ΔC p o of thymine being larger. Both transfer quantities ΔH t o and ΔC p,t o for the proceses H2O→DMSO for the two nucleic acid bases were negative. It is proposed that, the differences in the values obtained for the two bases is due principally to increased order in the water adjacent to the methyl group in thymine.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00647039
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