129812-35-7Relevant articles and documents
Furocoumarin-, Naphthofuran-, and Furoquinoline-Annulated 1,2-Dioxetanes: Synthesis, Thermolysis. and Mutagenicity
Adam, Waldemar,Hauer, Hermann,Mosandl, Thomas,Saha-Moeller, Chantu R.,Wagner, Willi,Wild, Dieter
, p. 1227 - 1236 (2007/10/02)
The low temperature photooxygenation of the furocoumarins 1a-e, the naphthofurans 1f-h, and the furoquinoline 1i afforded the corresponding dioxetanes 2 in good yields, except the linearly annulated napthofuran 1f, which led exclusively to the allylic hydroperoxide 5f by ene reaction with singlet oxygen.The dioxetanes 2 were rigorously purified by means of low temperature silicagel chromatography and fully characterized.Thermolysis of the furocoumarin dioxetanes 2a-e led to the expected cleavage products 3a-e (acetyloxy- and acetyl-substituted coumarins), while the naphtho- and quinolinofuran dioxetanes 2g-i gave in addition to the cleavage products 3g-i also the spiroepoxides 4g-i.Intramolecular electron transfer from the aromatic moiety to the dioxetane ring, with subsequent cyclization of the radical-ion species and fragmentation is postulated as mechanism for the formation of this novel rearrangement product of dioxetanes.On heating in chloroform the spiroepoxides 4g,h rearranged into the 1,4-dioxole 6g, but heating of 4g in methanol gave the dioxine 7g by trapping of the dipolar intermeadiate. - The furocoumarin dioxetanes 2a,c,d showed high mutagenic activity in the Salmonella typhimurium strain TA 100 but not in the strain TA 2638.The naphtho- and quinolinofuran dioxetanes 2h,i and the spiroepoxides 4g,h were nonmutagenic in the TA 100 strain.Epoxide-like DNA damage appears to be responsible for mutagenicity of the furocoumarin dioxetanes 2a,c,d.
