4H-1-benzopyran-4-one, 6-chloro-2-[(E)-2-(dimethylamino)ethenyl]- 6-chloro-2-[(E)-2-(dimethylamino)vinyl]-4H-chromen-4-one InChI=1/C13H12ClNO2/c1-15(2)6-5-10-8-12(16)11-7-9(14)3-4-13(11)17-10/h3-8H,1-2H3/b6-5