3',6'-Bis-diaethylamino-2-phenyl-spiro[isoindolin-1,9'-xanthen]-3-on, 3',6'-bis-diethylamino-2-phenyl-spiro[isoindole-1,9'-xanthen]-3-one, Spiro[1H-isoindole-1,9'-[9H]xanthen]-3(2H)-one,3',6'-bis(diethylamino)-2-phenyl, 3,6-Bis(diethylamino)-2'-phenylspiro[9H-xanthene-9,1'-[1H]isoindol]-3'(2'H)-one, 3',6'-bis(diethylamino)-2-phenylspiro(1H-isoindole-1,9'-[9H]xanthene)-3(2H)-one, 3',6'-bis-diethylamino-2-phenyl-spiro[isoindoline-1,9'-xanthen]-3-one, 3',6'-bis(diethylamino)-2-phenyl-2,3-dihydrospiro[isoindole-1,9'-xanthene]-3-one