Identification of isomeric dicaffeoylquinic acids from Eleutherococcus senticosus using HPLC‐ESI/TOF/MS and ¹H‐NMR methods

Abstract

Liquid chromatography-electrospray time-of-flight mass spectrometry (HPLC-ESI/TOF/MS) and a novel NMR technique, developed to maximise the sensitivity obtained from the standard NMR spectrometer, have been applied to the identification of the phenolic constituents of Eleutherococcus senticosus. In addition, molecular modelling and dihedral bond angle calculations based on the vicinal 3JHH-coupling constants have been used in the unambiguous assignment of signals in the 1H-NMR spectra. 5'-O-Caffeoylquinic acid and three isomeric compounds, 1',5'-O-dicaffeoylquinic acid, 3',5'-O-dicaffeoylquinic acid and 4',5'-O-dicaffeoylquinic acid, have been isolated and identified from a sample. The isolation and structure determination of the latter two compounds are reported for the first time from this plant.

Phenolics and antifungal activities analysis in industrial crop Jerusalem artichoke (Helianthus tuberosus L.) leaves

“…The structures of compounds 1-6 were determined by Mass Spectrometer (MS) and Nuclear magnetic resonance spectroscopy (NMR). The spectral data of the compounds were in agreement with those previously published (Lee et al, 2010;Peng et al, 2000;Tolonen et al, 2002).…”

“…These were identified as 3-o-caffeoylquinic acid (3-CQA), caffeic acid, 3,4-dicaffeoylquinic acid (3,4-DiCQA), 3,5-dicaffeoylquinic acid (3,5-DiCQA), 1,5-dicaffeoylquinic acid (1,5-DiCQA) and 4,5-dicaffeoylquinic acid (4,5-DiCQA) by comparing their UV, MS and 1 H and 13 C NMR spectral data with the data reported in previous studies (Peng et al, 2000;Tolonen et al, 2002;Lee et al, 2010). ).…”

Free radical scavenging activities and bioactive substances of Jerusalem artichoke (Helianthus tuberosus L.) leaves

“…With the aid of preparative HPLC described in Section 2.2, six compounds were isolated from the EA fraction. Among them, compound 1 was identified as 3-O-caffeoylquinic acid (3-CQA) by comparison of UV and retention time with reference compound; while compounds 2-6 were identified as caffeic acid (2), 3,5-dicaffeoylquinic acid (3,5-DiCQA, 3), 1,5-dicaffeoylquinic acid (1,5-DiCQA, 4), 4,5-dicaffeoylquinic acid (4,5-DiCQA, 5) and 3,5-dicaffeoylquinic acid methyl ether (3,5-DiCQAME, 6), respectively, by comparing their UV, MS, 1 H and 13 C NMR spectral data with the data reported in previous studies (Lee, Kim, Kim, Lee, & Kang, 2010;Peng, Mei, Jiang, Zhou, & Sun, 2000;Tolonen, Joutsamo, Mattlla, Kämäräinen, & Jalonen, 2002). Their structures are shown in Fig.…”

Mate Tea (Ilex paraguariensis) Promotes Satiety and Body Weight Lowering in Mice: Involvement of Glucagon-Like Peptide-1

“…6) The administered dose was calculated based on the amount of the aqueous powdered extract dissolved or sus- 13 C-NMR, and MS) previously reported [11][12][13][14][15] and those of standard compounds [chlorogenic acid (2), matesaponin 2 (3), caffeine (4), and rutin]. Of the major constituents isolated, we tested 3,5-O-dicaffeoyl-D-quinic acid (1), chlorogenic acid (2), matesaponin 2 (3), and caffeine (4).…”