Two Conformational Polymorphs of a Bioactive Pyrazolo[3,4-d]pyrimidine

Two monoclinic (P21/c; Z′ = 1) polymorphs, α (from methanol) and β ethanol, n-propanol iso-propanol), of a bioactive pyrazolo[3,4-d]pyrimidine derivative have been isolated characterised by X-ray crystallography as well range computational chemistry techniques. The different conformations observed for the molecules in crystals are due to dictates molecular packing revealed geometry-optimisation calculations. crucial difference pertains formation phenylamino-N–H···N(pyrazolyl) hydrogen bonding within supramolecular chains with either helical (α-form; 21-screw symmetry) or zigzag (β-form; glide symmetry). As consequence, is quite distinct polymorphs. Lattice energy calculations indicate β-form more stable 11 kJ/mol than α-form.