Find in Library

Two new compounds named 4,4′-bis(<i>β</i>-D-glucopyranosyloxy)biphenyl (<b>1</b>) and spirostane-25(27)-en-2<i>α</i>,3<i>β</i>-diol-3-<i>O</i>-<i>β</i>-D-xylopyranosyl(1→3)-<i>β</i>-D-glucopyranosyl(1→4)-<i>β</i>-D-galactopyranoside (<b>2</b>) were isolated from n-butanol extraction part of 80% ethanol extract of Allii Macrostemonis Bulbus. Alongside these, ten known compounds (<b>3–12</b>) were also identified, including a flavonoid glycoside (<b>3</b>), seven steroids (<b>4</b>–<b>10</b>), a nucleoside (<b>11</b>), and a phenylpropanoid glycoside (<b>12</b>) were found. Notably, compounds <b>3</b>–<b>6</b> were isolated from this plant for the first time. The structures of all compounds were confirmed using high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), 1D, and 2D NMR spectroscopy. Some of these compounds showed strong antioxidant activity, and compound <b>1</b> demonstrated the most potent reduction of ferric ions (Fe³⁺) with an IC₅₀ value of 0.59 ± 0.18 mg/mL. Compounds <b>2</b> and <b>3</b> exhibited the highest scavenging activity against superoxide anion radicals (O₂⁻·) with an IC₅₀ value of 0.02 ± 0.01 mg/mL. Additionally, compound <b>3</b> displayed substantial scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) with IC₅₀ values of 0.21 ± 0.17 mg/mL and 0.02 ± 0.01 mg/mL, respectively. The discovery of these two new compounds is a reference for identifying Allii Macrostemonis Bulbus quality markers. Moreover, their exceptional antioxidant activity offers a promising avenue for uncovering novel natural antioxidants.