organic compounds
Conformational analyses and structural comparison of the title spiropyrazolebarbiturate, C19H16N4O4·C3H6O·H2O, and the related structure 3-bromo-1,4-diphenyl-1,2,7,9-tetraazaspiro[5.4]dec-2-ene-6,8,10-trione acetone solvate [Bruno, Rotondo, Nicoló, Foti, Grassi & Risitano (2005). Acta Cryst. E61, o142-o144], are presented. Both compounds were synthesized by cycloaddition of C-H and C-Br nitrilimines, generated in situ, starting from the same substrate [Foti, Grassi & Risitano (2005). Synlett. Submitted]. However, different experimental conditions led to products with reverse regioselectivity.
organic compounds
Conformational analyses and structural comparison of the title compound, C18H13BrN4O3·C2H6O, and the related compound 4-(4-methoxyphenyl)-3-phenyl-2,4,8,10-tetraazaspiro[5.4]dec-1-ene-6,8,10-trione acetone solvate monohydrate [Bruno, Rotondo, Nicoló, Foti, Grassi & Risitano (2005). Acta Cryst. E61, o139-o141], co-crystallized with solvent molecules, are presented. Both compounds were synthesized by the cycloaddition of C-H and C-Br nitrilimines, generated in situ, starting from the same substrate [Foti, Grassi & Risitano (2005). Synlett. Submitted]. However, different experimental conditions led to products with reverse regioselectivity.