[摘要]：A systematic phytochemical investigation on Abies forrestii afforded two new and 20 known compounds. Abieseconordines A and B (1 and 2) are the first two examples of norditerpenes with a novel 18-nor-5,10?:?9,10-disecoabietane skeleton. Their structures were established mainly by analysis of 1D- and 2D-NMR spectroscopic data. In addition, electronic circular-dichroism calculations and molecular-orbital analysis were utilized to confirm the absolute configuration of 1. Both compounds exhibited a potent effect in a bioassay inhibiting LPS-stimulated NO production in RAW264.7 macrophages.
