Enrique Barrero Rodríguez

Stereoselective synthesis of pyrazoline derivatives by 1,3-dipolar cycloaddition of diazoalkanes to α,β-unsaturated carbonyl derivatives of sugars

New pyrazoline acyclonucleosides have been prepared by 1,3-dipolar cycloaddition reactions of diazoalkanes to derivatives of d-galacto-oct-2-enonate and d-galacto-non-3-enulose. The reactions were highly regio- and stereo-selective, and single isomers were obtained in good yields. A tautomeric equilibrium between the 1- and 2-pyrazoline structures was observed for some of the isomers in solution.