Volvalerenone A, a new type of mononorsesquiterpenoid with an unprecedented 3, 12-oxo bridge from Valeriana officinalis - Wang, P C; Ran, X H; Chen, R; Li, L C; Xiong, S S; Liu, Y Q; Luo, H R; Zhou, J; Zhao, Y X (Tetrahedron Lett, 2010)