(5'R)-5'-hydroxy-2',5',7'-trimethylspiro[cyclopropane-1,6'-indene]-4'-one (5'R)-5'-hydroxy-2',5',7'-trimethyl-spiro[cyclopropane-1,6'-indene]-4'-one (5'R)-5'-hydroxy-2',5',7'-trimethyl-4'-spiro[cyclopropane-1,6'-indene]one Acylfulvene NSC633555 NCI60_011189