60796-65-8Relevant articles and documents
HIGHLY OXYGENATED COUMARINS FROM PELARGONIUM SIDOIDES
Kayser, Oliver,Kolodziej, Herbert
, p. 1181 - 1186 (1995)
The sample of natural simple coumarins is extended by discovery of the highly oxygenated representatives 6,8-dihydroxy-7-methoxycoumarin, 6,7,8-trihydroxycoumarin, 6,8-dihydroxy-5,7-dimethoxycoumarin, and 7-acetoxy-5,6-dimethoxycoumarin.They are accompanied in the roots of Pelargonium sidoides by the widely occuring scopoletin, associated with the uncommon analoges 5,6,7-trimethoxycoumarin, 7-hydroxy-5,6-dimethoxycoumarin (umckalin), and 5,6,7,8-tetramethoxycoumarin (artelin), these being reported from a plant source for the second time.The structures of these compounds were established from chemical and spectroscopic studies.Differentiation between oxygenation patterns is discussed on the basis of chemical shift data.
Total synthesis of naturally occurring 5,6,7- and 5,7,8-trioxygenated coumarins
Maes, Dominick,Riveiro, Maria Eugenia,Shayo, Carina,Davio, Carlos,Debenedetti, Silvia,De Kimpe, Norbert
, p. 4438 - 4443 (2008/09/21)
The synthesis of five naturally occurring polyoxygenated coumarins is described. It concerns two 5,6,7-trioxygenated coumarins, i.e., 6-hydroxy-5,7-dimethoxycoumarin (fraxinol) 1 and 5,6,7-trimethoxycoumarin 2, and three 5,7,8-trioxygenated coumarins, i.e., 8-hydroxy-5,7-dimethoxycoumarin (leptodactylone) 3, 5,7,8-trimethoxycoumarin 4 and 8-(3-methyl-2-butenyloxy)-5,7-dimethoxycoumarin (artanin) 5. Key feature of the synthetic pathway is the synthesis of suitable tetraoxygenated benzaldehydes, which are then converted to the corresponding coumarins via a Wittig reaction.