ChemInform Abstract: Studies on the Constituents of Brazilian Propolis.

Seven new p-coumaric acid derivatives along with seventeen known compounds, including four flavonoids, one prenylated phenolic acid, four diterpenoic acids, one lignan, two p-coumaric acid esters and five cinnamic acid derivatives, were isolated from the ethyl acetate soluble fraction of 75% ethanol extract of Brazilian propolis. New compounds were elucidated as (E)-2, 3-dihydroconiferyl p-coumarate, (E)-3-{2, 3-dihydro-2-[2-[(E)-p-coumaroyloxy]-1-methylethyl]-5-benzofuranyl}-2-propenoic acid, (E)-4-(2, 3-dihydrocinnamoyloxy)cinnamic acid, (E)-3-(2, 2-dimethyl-3, 4-dihydro-3-hydroxy-2H-1-benzopyran-6-yl)-2-propenoic acid, (E)-3-[2, 3-dihydro-2-(1-methylethenyl)-5-benzofuranyl]-2-propenoic acid, (E)-3-[2, 3-dihydro-2-(1-methylethenyl)-7-prenyl-5-benzofuranyl]-2-propenoic acid and (E)-3-{3-[(E)-4-(2, 3-dihydrocinnamoyloxy)-3-methyl-2-butenyl]-4-hydroxy-5-prenylphenyl}-2-propenoic acid, on the basis of spectral evidence and chemical reaction. Five compounds : dihydrokaempferol (aromadendrin), 6-methoxykaempferol, 4-hydroxy-3-prenylbenzoic acid, plicatin B and capillartemisin A, were isolated from propolis for the first time.