Comprehensive Summary Chemical investigation of Fritillaria verticillata Willd. led to the isolation of eight novel isosteroidal alkaloids (1-4, 6, 9-11) and four known alkaloids (5, 7-8, 12), including three unprecedented cis-fused D/E (13 alpha, 17 alpha) cevanine alkaloids (1-3), one rarely cis-fused E/F (22 alpha) cevanine alkaloid (6), and one uncommon 5 beta-jervine-type isosteroidal alkaloid featuring a cis-fused A/B ring moiety (11). In order to establish the structures of 1, the calculated NMR with DP4+ evaluation was applied from the plausible structure candidates. The characteristic proton signals for distinguishing D/E conjunction of cevanine alkaloids were summarized. In addition, some proton and carbon signals alpha to nitrogen in 6 and 7 are unobservable due to the N-14 nuclear quadrupolar relaxation, based on the NMR experiments in different solvents, calculated NMR method and X-ray technology, their structures were determined. The NMR characteristics of cevanine alkaloids to distinguish orientation of long-pair on nitrogen atom with beta-hydroxyl at C-20 were also concluded. The anti-inflammatory effects of compounds 1 and 4 were evaluated in LPS-activated RAW 264.7 macrophages. Compound 4 decreased LPS-induced releases of IL-1 beta and IL-17 alpha in RAW264.7 cells in a dose-dependent manner. Further mechanistic study revealed that 4 suppressed the phosphorylation of I kappa B alpha and p65 subunit to regulate the NF-kappa B signaling pathway.