Calculation of the structure and evaluation of the reactivity of N-methyl-N-(β-d-xylopyranosyl)-N-nitrosourea under acid-base catalysis conditions

An investigation of N-methyl-N-(-D-xyloxyl)urea (I) and its nitroso derivative (II) has been carried out in the MINDO/3 approximation by the MO-LCAO method. It has been shown that the very significant difference between the energies of molecule I in the free state and in a crystal is due to the potential energy of the crystal field and intermolecular hydrogen bonds. An analysis of the distribution of the charges on the atoms showed that the most probable site for protonation and nucleophilic attack in I and II is the carbonyl group. A picture of the changes in the electronic structure and properties of the reaction centers in I and II under model acid-base catalysis conditions has been obtained.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 21, No. 5, pp. 596–599, September–October, 1985.