Triculata A, a novel compound from Tricyrtis maculata (D. Don) J. F. Macbr. with biological properties

A novel compound, triculata A (1), and seven known compounds were obtained from the Tricyrtis maculata (D. Don) J. F. Macbr.. The structure of the new compound was determined by extensive spectroscopic methods, and its absolute configuration was assigned by single-crystal X-ray diffraction analysis. Compound 1 features a rare naphtho[b,c]pyran carbon skeleton that was found in nature for the first time. Compounds 2-4, 6 and 7 showed potential vasodilatory effects with EC₅₀ values ranging from 7.3 to 111.3 μM. Compounds 1, 3-5 and 7 possessed remarkable antioxidant capacity evaluated by DPPH and ABTS assays.