Phenolic compounds from tournefortia sarmentosa

Three new isoprenylbenzenes, tournefolins A (1), B (2), and C (3), and two new 2-ethoxy-4,5-dihydroxybenzoyl compounds, 4 and 5, together with the known compounds, salicylic acid and allantoin, were isolated from the stems of Tournefortia sarmentosa. The structures of new compounds were elucidated as 2-(4beta-methyltetrahydrofuran-2alpha-yl)-5-(4beta-methyltetrahydrofu ran-2beta-yl)-1,4-dihydroxybenzene (1), methyl 5-(5-hydroxy-2-methoxyphenyl)-3-furoate (2), methyl 5-(2, 5-dihydroxyphenyl)-3-furoate (3), 2-ethoxy-4,5-dihydroxybenzaldehyde (4), and 2-ethoxy-4,5-dihydroxybenzoic acid (5), on the basis of spectral and chemical methods. The relative configuration of 1 was determined by single-crystal X-ray crystallography.