Effect of the structure and substituents on the proton affinity of immunoactive azasteroid molecules
Annotatsiya
The effect of the structure and substitution on the proton affinity of immunoactive 8-azasteroid molecules was studied by semi-empirical methods of the quantum chemistry. It was shown that the proton affinity of these molecules is determined by the carbonyl oxygen atoms. The methoxy substitutents on the aromatic ring of the steroid have a weak effect on the proton affinity of the molecules in the ground state, whereas the direction of the effect for excited molecules depends on the orbital nature of the excited state. The substitution of the NH group or oxygen in the 16-position causes a substantial increase in the proton-acceptor power. The reasons for these changes are discussed.