This work addresses the issues of the synthesis and study the chemical properties of the 4H,8H-pyrano[2,3-f]chromene-4,8-diones with heterocycles incorporated at C-3 and C-9. An efficient synthesis of 4H,8H-pyrano[2,3-f]chromene-4,8-diones has been undertaken starting from 8-formyl-7-hydroxychromones. 8-Formyl-7-hydroxychromones have been prepared via Duff reaction in good yields. Reaction of 8-formyl-7-hydroxychromones with nucleophiles has been studied and a series of functional derivatives obtained. Knoevenagel reaction was applied to provide 4H,8H-pyrano[2,3-f]chromene-4,8-diones. It proceeded smoothly and gave 4H,8H-pyrano[2,3-f]chromene-4,8-diones in 70-90% yields. The advantage of our approach is centered around using mild conditions that enable isolation of the 8-imino-4H-pyrano[2,3-f]chromene-4-ones which then subjected to hydrolysis with the mixture of the hydrochloric and acetic acid in high yields. The cleavage with binucleophiles has been employed to 4H,8H-pyrano[2,3-f]chromene-4,8-diones. It was found that ?-pyrone cycle proved to be unreactive under treatment of 4H,8H-pyrano[2,3-f]chromene-4,8-diones with hydroxylamine. Reaction proceeded exclusively with the recyclisation of the gamma-pyrone cycle to afford 6-(1,2-oxazol-5-yl)-2H-chromene-2-ones. On the contrary, 4H,8H-pyrano[2,3-f]chromene-4,8-diones undermine recyclisation both alpha-and gamma-pyrone cycles under treatment with hydrazine producing hydrazone which then was converted into azine. Using the 2-aminocrotonate ester in reaction with 7-hydroxy-8-formyl-chromones allows obtaining 5Н,9Н-pyrano[2,3:5,6]chromeno[4,3-b]pyridine-5,9-diones, which then subjected to the cleavage with hydrazine and hydroxylamine to furnish 9-[4-(4-chlorophenyl)-3-methyl-1,2-oxazole-5-yl] and 9-[4-(4-chlorophenyl)-3-methyl-1H-pyrazole-5-yl] derivatives of the 5H-chromeno[4,3-b]pyridin-5-one system. It was shown that 8-[3-(dimethylamino)prop-2-enoyl]-7-hydroxy-4H-chromen-4-one is versatile compound for the 4H,10H-pyrano[2,3-f]chromene-4,10-dione synthesis. All structures were proven by 1H,13C NMR, IR-, Mass-spectrae and X-ray
