title: [Studies on hydroxyfluoran and its derivatives as organic reagents. VI. 2',3',6',7'-Hydroxyfluoran derivatives as metallochromic indicators].
mesh_terms: D006571:Heterocyclic Compounds; D007202:Indicators and Reagents; D008670:Metals; D011083:Polycyclic Compounds
chemical_list: D006571:Heterocyclic Compounds; D007202:Indicators and Reagents; D008670:Metals; D011083:Polycyclic Compounds