Cuauthemone sesquiterpenes and flavones from Laggera tomentosa endemic to Ethiopia

Abstract

Three sesquiterpenes, 3-O-(3’-acetoxy-2’-hydroxy-2’-methylbutyryl)cuauthemone (1), 4-O-acetylcuauthemone-3-O-angelate (2), 4-O-acetylcuauthemone 3-O-(2’-hydroxy-2’-methyl-3’-acetoxybutyrate) (3) and two flavones, 3’,4’,5,7-tetrahydroxy-3,6-dimethoxyflavone (4), 3’,5,6-trihydroxy-3,4’,7-trimethoxyflavone (5) were isolated from the aerial parts of Laggera tomentosa. The compounds were characterized using spectroscopic techniques. Complete ¹H and ¹³C NMR assignment of compound 1 was done for the first time. This is the first report on the occurrence of cuauthemone sesquiterpenes in the genus Laggera.

KEY WORDS: Laggera tomentosa, Asteraceae, Cuauthemone sesquiterpenes, 3-O-(3’-acetoxy-2’-hydroxy-2’-methylbutyryl)cuauthemone

Bull. Chem. Soc. Ethiop. 2010, 24(2), 267-271.