Selaginpulvilins A–D, New Phosphodiesterase-4Inhibitors with an Unprecedented Skeleton from Selaginellapulvinata.

SelaginpulvilinsA–D (1–4), four new phenolswith an unprecedented 9,9-diphenyl-1-(phenylethynyl)-9H-fluorene skeleton, together with four known selaginellins(5–8) were isolated from Selaginella pulvinata. Their structures were elucidatedby spectroscopic analysis and chemical correlation. The structureof 1was confirmed by single-crystal X-ray diffraction.Compounds 1–8exhibited remarkableinhibitory activities (IC50values in the range of 0.11–5.13μM) against phosphodiesterase-4 (PDE4), a drug target for thetreatment of asthma and chronic obstructive pulmonary disease. [ABSTRACT FROM AUTHOR]