2-pyridone and 3-oxo-1,2,6-thiadiazine-1,1-dioxide derivatives: a new class of hydrogen bond equivalents of uracil
Hydrogen bond complex stability between adenine ( A) and hydrogen bond equivalents of uracil: 2-pyridone derivatives (U-X2O(X)) and 3-oxo-1,2,6-thiadiazine-1,1-dioxide derivatives (U-SO2(X)) was studied, and as the result, the hydrogen bond energy of U-X2O(X)-A and a complex of UXSO2X-A, was about 1.5 kcal/mol more stable than that of the corresponding adenine-uracil derivatives complex, respectively. The energy difference between the imide tautomer and enol tautomer was smaller than those of uracil derivatives. U-SO2(F) can form a stable complex with A, and its imide tautomer is stable.
hydrogen bonding molecular orbital substitution effect