7-hydroxy-3-oxo-3H-phenoxazine-4-carboxylic acid
Chemical Formula: C13H7NO5
Molecular Weight: 257.2010
m/z: 257.0324 (100.0%), 258.0358 (14.1%), 259.0367 (1.0%)
Elemental Analysis: C, 60.71; H, 2.74; N, 5.45; O, 31.10

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