Antioxidant and Anti-inflammatory Active Dihydrobenzofuran Neolignans from the Seeds of Prunus tomentosa

Prunus tomentosa seeds were researched for antioxidant and anti-inflammatory constituents. By activity-guided fractionation of <i>P. tomentosa</i> seed extract, six new dihydrobenzofuran neolignans, prunustosanans AI-IV (<b>1</b>–<b>4</b>) and prunustosanansides AI and AII (<b>5</b> and <b>6</b>), together with 10 known compounds (<b>7</b>–<b>16</b>) were isolated from bioactive fraction. The structures were determined by spectroscopic analyses, especially NMR, HRESIMS, and CD spectra. The antioxidant activity was greatest for <b>5</b>, <b>10</b>, and <b>12</b> against DPPH radical and for <b>8</b>, <b>9</b>, and <b>13</b> against ABTS radical. Moreover, compounds <b>7</b> and <b>11</b> exhibited much stronger inhibitory activity on nitric oxide (NO) production in murine microglia BV-2 compared with positive control minocycline (IC₅₀ = 19.7 ± 1.5 μM). The results show that <i>P. tomentosa</i> seeds can be regarded as a potential source of antioxidants and inflammation inhibitors