关环闭环的产物都可以

4-((3′,6′-dihydroxy-3-oxospiro[isoindoline-1,9′-xanthen]-2-yl)amino)benzoic acid
Chemical Formula: C27H18N2O6
Molecular Weight: 466.4490
m/z: 466.1165 (100.0%), 467.1198 (29.2%), 468.1232 (4.1%), 468.1207 (1.2%)
Elemental Analysis: C, 69.52; H, 3.89; N, 6.01; O, 20.58

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