(±)-Peniorthoesters A and B Two Pairs of Novel Spiro-Orthoester en-antiomers With an Unusual 146-Trioxaspi-ro4.5decane-7-One Unit From Penicillium minioluteum

摘要

(±)-Peniorthoesters A and B (±>1 and ±>2), two pairs of unprecedented spiro-orthoester enantiomers with a 1,4,6-trioxaspiro[4. 5]decane-7-one unit, were obtained from Penicillium minioluteum. Their structures were determined by spectroscopic methods, X-ray diffraction analyses, and ECD calculations. (±)-Peniorthoesters A and B are the first examples of spiro-orthoester enantiomers, and they represent the first spiro-orthoesters originating from fungi. All compounds showed potential inhibitory activities comparable to dexamethasone against NO production with IC50 values ranging from 14.2 to 34.5 μM.