Citrifurans A–D, Four Dimeric Aromatic Polyketides with New Carbon Skeletons from the Fungus Aspergillus sp.

• DOI: 10.1021/acs.orglett.7b01823
• Publication Date: 2017-07-20T15:39:18Z
• Authors: Guo-Ping Yin; Ya-Rong Wu; Ming-Hua Yang; Tian-Xiao Li; Xiao-Bing Wang; Miao-Miao Zhou; Jian-Li Lei; Ling-Yi Kong
• Keywords: Carbon fibers

Citrifurans A-D (1-4), metabolized by an Aspergillus sp., are unusual dimers of azaphilone and furanone derivatives. Michael addition was thought to be the pivotal procedure in their biosynthesis, different sites generated two new carbon skeletons. Their structures were elucidated on basis spectroscopic methods, single-crystal X-ray diffraction, chemical conversion, electronic circular dichroism analyses. Compounds 1-3 showed moderate inhibitory activities against LPS-induced NO production RAW 264.7 macrophages with IC50 values 18.3, 22.6, 25.3 μM, respectively.