Eudesmane-Type Sesquiterpenoid and Guaianolides from Kandelia candel in a Screening Program for Compounds to Overcome TRAIL Resistance

In a screening program for natural products that can overcome TRAIL resistance, a new eudesmane-type sesquiterpenoid (1), three new guaianolides, mehirugins A–C (24), and two known guaianolides (5 and 6) were isolated from a MeOH extract of Kandelia candel leaves. Compounds 1 and 36 in combination with TRAIL showed cytotoxic activity in sensitizing TRAIL-resistant human gastric adenocarcinoma cells.