Isolation and Identification of 3-(3,4-Dihydroxyphenyl)-2-propenoic acid fromMethyl acetate root bark extractof Cassia sieberiana
Magashi LA, Adamu HM, Kolo AM, Hassan UF
The Caffeic acid (3-(3,4-Dihydroxyphenyl)-2-propenoic acid) was isolated from Cassia sieberiana root bark using standard analytical methods and the main compound with [ M + H] mass of 360 m/z with retention time of 0.495 in positive mode and 0.392 in negative mode, by exhibiting the base peak ion at 359 m/z was identified. Dimer of Caffeic acid was isolated and fully characterized with concerted use of FTIR, LCMS, HNMR, 13CNMR spectroscopy and CHN analysis. The CHN calculations from the empirical formular C2H2O (42 g) and the actual mass of the compound was calculated to be 378 g/mol by comparing molecular weight obtained from MS (360 m/z). C18H18O9 (378 g/mol) with loss of water molecule (18 g/mol) gave a compound of mass 360 g/mol (C18H16O8) which is the dimer of caffeic acid 180 g (C9H8O4) (39) and subsequence loss of water gave the actual mass of dicaffeic acid (C18H14O7) (38) are in agreements with experimental results confirmed the identity of the isolated natural product.