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organic compounds
The title compound, C9H12N4O5, adopts a distinct ring-twisted conformation defined by nearly orthogonal bridgehead torsion angles [C16-C15-C14-N19 of -90.1 (2) and C26-C25-C24-N29 of -87.8 (2)°]. The antiperiplanar array [C17-O14-C14-N19 of -158.0 (2) and C27-O24-C24-N29 of -158.3 (2)°] does not allow stereoelectronically controlled ring-opening at the C4-N9 bond.