(E)-8-(3,4-dimethoxyphenyl)-4-methyl-7,8-dihydropyrano[3,2-g]chromene-2,6-dione

(E)-7-hydroxy-6-[3-(2-methoxyphenyl)acryloyl]-4-methyl-2H-chromen-2-one

(E)-8-(2-methoxyphenyl)-4-methyl-7,8-dihydropyrano[3,2-g]chromene-2,6-dione

4-methyl-2,8-dioxo-2H,8H-pyrano[2,3-f]chromene-9-carbonitrile

ethyl 8-imino-4-methyl-2-oxo-2H,8H-pyrano[2,3-f]chromene-9-carboxylate