Quantitative Analysis of Caffeoylquinic Acids and Styrylpyrones in Sweetia panamensis Bark by UPLC

Six secondary metabolites from the methanolic extract of Sweetia panamensis (Fabaceae) bark were isolated and characterised. Along with the pyrones desmethylangonine β-d-O-glucopyranoside and desmethylangonine β-d-O-glucopyranosyl-(1→6)-O-β-d-glucopyranoside, already reported in this species, 5-O-caffeoylquinic acid (chlorogenic acid), 4-O-caffeoylquinic acid, 3-O-caffeoylquinic acid and the isoflavonoid 5-O-methylgenistein 7-O-β-d-glucopyranoside were isolated for the first time from S. panamensis. Additionally, an LC-ESI-MS qualitative analysis was performed and an ultra performance liquid chromatography (UPLC) method was developed and validated for the determination of these compounds. The UPLC method was applied to the quantitative analysis of plant samples. Pyrones and caffeoylquinic acids resulted to be the main compounds in the extract; in particular desmethylangonine β-d-O-glucopyranosyl-(1→6)-O-β-d-glucopyranoside was the most abundant compound.