2,7-Dimethyl-4,5-dihydro-pyrano(4,3-b)pyran-4,5-dione 2,7-Dimetil-4H,5H-pirano(4,3-b)piran-4,5-dione [Italian] 33176-11-3 4H,5H-Pyrano(4,3-b)pyran-4,5-dione, 2,7-dimethyl- 5-19-05-00100 (Beilstein Handbook Reference) BRN 1243698