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The ethyl acetate fraction of the methanolic extract of <i>Yucca schidigera</i> Roezl ex Ortgies bark exhibited moderate acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity (IC₅₀ 47.44 and 47.40 &#181;g mL^&#8722;1, respectively). Gel filtration on Sephadex LH-20 and further RP-C₁₈ preparative HPLC of EtOAc fraction afforded 15 known and 3 new compounds, stereoisomers of larixinol. The structures of the isolated spirobiflavonoids <b>15</b>, <b>26</b>, and <b>29</b> were elucidated using 1D and 2D NMR and MS spectroscopic techniques. The relative configuration of isolated compounds was assigned based on coupling constants and ROESY (rotating-frame Overhauser spectroscopy) correlations along with applying the DP4+ probability method in case of ambiguous chiral centers. Determination of absolute configuration was performed by comparing calculated electronic circular dichroism (ECD) spectra with experimental ones. Compounds <b>26</b> and <b>29</b>, obtained in sufficient amounts, were evaluated for activities against AChE and BChE, and they showed a weak inhibition only towards AChE (IC₅₀ 294.18 &#181;M for <b>26</b>, and 655.18 &#181;M for <b>29</b>). Furthermore, molecular docking simulations were performed to investigate the possible binding modes of <b>26</b> and <b>29</b> with AChE.