{Reference Type}: Journal Article {Title}: Dereplication of bioactive constituents of the genus hypericum using LC-(+,-)-ESI-MS and LC-PDA techniques: Hypericum triquterifolium as a case study. {Author}: Alali FQ;Tawaha K; {Journal}: Saudi Pharm J {Volume}: 17 {Issue}: 4 {Year}: Oct 2009 {Factor}: 4.562 {DOI}: 10.1016/j.jsps.2009.10.002 {Abstract}: Utilizing liquid chromatography-electro spray ionization-mass spectrometry (LC-(+,-)-ESI-MS) and liquid chromatography-photodiode array detection (LC-PDA) techniques, a dereplication strategy for the analysis of the secondary metabolites constituents of the genus Hypericum has been developed. From the crude methanolic extract of the aerial parts of H. triquetrifolium (leaves, stems, and flowers) and on the basis of their UV-profiles, chromatographic retention times and (+,-)-ESI-MS (TIC and SIM) mass spectral data, seven known (1-7) compounds were dereplicated fairly rapidly. The compounds were classified into three structural classes: phloroglucinols: hyperfirin and adhyperfirin; naphthodianthrones: hypericin, pseudo-hypericin, proto-hypericin, and protopseudo-hypericin; and the flavonoid rutin.