(Z)-2-[2-(4-Fluorophenyl)-4-oxo-4H,5H-pyrazolo[1,5-a]pyrazin-5-yl]-N'-hydroxyethenimidamide(Z)-2-[2-(4-Fluorophenyl)-4-oxo-4H,5H-pyrazolo[1,5-a]pyrazin-5-yl]-N'-hydroxyethenimidamide