A new selaginellin derivative and a new triarylbenzophenone analog from the whole plant of Selaginella pulvinata

Five selaginellin derivatives (1 and 3–6) including a new one, selaginellin T (1), and a new triarylbenzophenone analog, selagibenzophenone A (2), were isolated from the whole plants of Selaginella pulvinata. Their structures were determined by 1D- and 2D-NMR and HR-ESI-MS data. Selagibenzophenone A (2) is the first example of naturally occurring triarylbenzophenone. The results of the phosphodiesterase-4 (PDE4) inhibitory screening assays showed that compounds 1−6 exhibited potent activities with the IC₅₀ values in the range of 1.04−9.35 μM.