The crystal structure of the title compound, C7H7NO3, shows a strong q
uinoid character. The oximic function is anti with respect to the meth
oxy group so that no intramolecular hydrogen bonds involving the acidi
c H atom are formed, instead a strong intermolecular interaction is fa
voured. Two molecules an present in the asymmetric unit and they show
no significant differences in their bond lengths and angles, but they
do have different packing interactions.