AUTHOR=Liu Xiaorui , Chen Chunmei , Zheng Yinyu , Zhang Mi , Tong Qingyi , Liu Junjun , Zhou Qun , Wang Jianping , Luo Zengwei , Zhu Hucheng , Zhang Yonghui 

TITLE=(±)-Peniorthoesters A and B, Two Pairs of Novel Spiro-Orthoester en-antiomers With an Unusual 1,4,6-Trioxaspi-ro[4.5]decane-7-One Unit From Penicillium minioluteum

JOURNAL=Frontiers in Chemistry

VOLUME=6

YEAR=2018

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2018.00605

DOI=10.3389/fchem.2018.00605

ISSN=2296-2646

ABSTRACT=<p>(±)-Peniorthoesters A and B (±<bold>1</bold> and ±<bold>2</bold>), two pairs of unprecedented spiro-orthoester enantiomers with a 1,4,6-trioxaspiro[4. 5]decane-7-one unit, were obtained from <italic>Penicillium minioluteum</italic>. 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 IC<sub>50</sub> values ranging from 14.2 to 34.5 μM.</p>