<jats:title>Abstract</jats:title><jats:p>Three new alkaloids, 2′‐<jats:italic>O</jats:italic>‐<jats:italic>β</jats:italic>‐<jats:sc>D</jats:sc>‐glucopyranosyl‐11‐hydroxyvincoside lactam (<jats:bold>1</jats:bold>), 22‐<jats:italic>O</jats:italic>‐demethyl‐22‐<jats:italic>O</jats:italic>‐<jats:italic>β</jats:italic>‐<jats:sc>D</jats:sc>‐glucopyranosylisocorynoxeine (<jats:bold>2</jats:bold>), and (4<jats:italic>S</jats:italic>)‐corynoxeine <jats:italic>N</jats:italic>‐oxide (<jats:bold>3</jats:bold>) were isolated from the leaves of <jats:italic>Uncaria rhynchophylla</jats:italic>, together with four known tetracyclic oxindole or indole alkaloids, isocorynoxeine <jats:italic>N</jats:italic>‐oxide (<jats:bold>4</jats:bold>), rhynchophylline <jats:italic>N</jats:italic>‐oxide (<jats:bold>5</jats:bold>), isorhynchophylline <jats:italic>N</jats:italic>‐oxide (<jats:bold>6</jats:bold>), and dihydrocorynantheine (<jats:bold>7</jats:bold>), and an indole alkaloid glycoside, strictosidine (<jats:bold>8</jats:bold>). The structures of <jats:bold>1</jats:bold>–<jats:bold>3</jats:bold> were elucidated by spectroscopic methods including UV, IR, ESI‐TOF‐MS, 1D‐ and 2D‐NMR, as well as CD experiments. The activity assay showed that <jats:bold>8</jats:bold> (<jats:italic>IC</jats:italic><jats:sub>50</jats:sub>=8.3 μ<jats:sc>M</jats:sc>) exhibited potent inhibitory activity on lipopolysaccharide(LPS)‐induced nitrogen monoxide (NO) release in N9 microglia cells. However, only weak inhibitory activities were observed for <jats:bold>1</jats:bold>–<jats:bold>7</jats:bold> (<jats:italic>IC</jats:italic><jats:sub>50</jats:sub>>100 μ<jats:sc>M</jats:sc> for <jats:bold>1</jats:bold>–<jats:bold>6</jats:bold> or >30 μ<jats:sc>M</jats:sc> for <jats:bold>7</jats:bold>).