Structural analysis of chlorogenic acid from red clover (Trifolium pratense) extract

Abstract

This paper presents the results of a structural analysis of chlorogenic acid isolated from a 70% ethanol extract of red clover (Trifolium pratense) callus culture. X-ray phase analysis showed that the sample was crystalline and single-phase and crystallized in an orthorhombic unit cell with the following parameters: a = 36.7548(5) [A], b = 11.0770(3) [A], c = 7.7947(2) [A], V = 3173.46(11) [A]3, R-Bragg = 0.347 %, Rexp = 4.75 %, Rwp = 5.83 %, Rp = 4.39 %, GOF = 1.23 %. NMR spectroscopy data (1H, 13C{1H}, 2D 1H1H-COSY, 1H13C-HSQC, 1H13C-HMBC) confirmed that the chemical structure and purity of the sample fully corresponded to chlorogenic acid, with no chemical impurities detected. Complete proton and carbon atom assignments are provided.