New pyridocarbazole alkaloids from <i>Strychnos nitida</i>

<p>Phytochemical investigation of <i>Strychnos nitida</i> has led to the isolation of three new racemic pyridocarbazole alkaloids, (±)-stritidas A-C (<b>1</b>–<b>3</b>) and three known monoterpenoid indole alkaloids (<b>4</b>–<b>6</b>). Compounds <b>2</b> and <b>3</b> represent the first examples of pyridocarbazole alkaloids featuring an <i>N</i>-2-hydroxyethyl moiety. Their structures were determined by combined spectroscopic data (MS, UV, IR and NMR) and chemical methods.</p>