Sesquiterpenoids and triterpenoids from Abies holophylla and their bioactivities.

Six previously unreported and 11 known terpenoids were isolated from Abies holophylla. The structures of the six compounds were established as two unusual bisabolane sesquiterpenoids, three nortriterpenoids, and one 3,4-seco-triterpenoid based on the detailed analysis of their 1D and 2D NMR spectroscopic data. In addition, electronic circular dichroism (ECD) calculations and molecular orbital (MO) analysis were used to assign the absolute configuration of one bisabolane sesquiterpenoid, abiesesquine A. Abiesesquine A showed the strongest inhibitory effects against LPS-induced nitric oxide (NO) production in RAW264.7 macrophages with an IC(50) value of 113.1 μM. Lanosta-7,9(11),24-trien-26-oic acid showed potent cytotoxic activity against COLO-205, LOVO, and QGY-7703 tumor cells with IC(50) values of 0.9, 4.2, and 2.0 μM, respectively. (23R,25R)-3,4-seco-9βH-Lanosta-4(28),7-dien-26,23-olid-3-oic acid, exhibited a significant antiproliferation effect against A549 cells (IC(50)=14.7 μM).