Meroterpenoids from the Fungus Ganoderma sinensis and First Absolute Configuration Clarification of Zizhine H

Five new meroterpenoids, zizhines P-S and U (1-4,7), together with two known meroterpenoids (5 and 6) were isolated from Ganoderma sinensis. Their structures including absolute configurations were assigned by using spectroscopic, computational, and chemical methods. Racemics zizhines P and Q were purified by HPLC on chiral phase. Biological evaluation found that 4, 5 and 6 are cytotoxic toward human cancer cells (A549, BGC-823, Kyse30) with IC50 values in the range of 63.43-80.83 mu M towards A549, 59.2 +/- 2.73 mu M and 64.25 +/- 0.37 mu M towards BGC-823, 76.28 +/- 1.93 mu M and 85.42 +/- 2.82 mu M towards Kyse30.