Cytosporones W and X: Two Mutually Converting Epimers from a Mangrove Endophytic Fungus Diaporthe sp. ZJHJYZ-1

Yihao Yin; Wencong Yang; Tao Chen; Qi Tan; Ge Zou; Zhenming Zang; Jiehui Li; Bo Wang; Zhigang She

doi:10.1021/acsomega.3c03862

Cytosporones W and X: Two Mutually Converting Epimers from a Mangrove Endophytic Fungus Diaporthe sp. ZJHJYZ-1

ACS Omega. 2023 Jul 10;8(29):26628-26634. doi: 10.1021/acsomega.3c03862. eCollection 2023 Jul 25.

Authors

Yihao Yin¹, Wencong Yang¹, Tao Chen¹, Qi Tan¹, Ge Zou¹, Zhenming Zang¹, Jiehui Li¹, Bo Wang¹, Zhigang She¹

Affiliation

¹ School of Chemistry, Sun Yat-sen University, Guangzhou 510006, China.

Abstract

Two new octaketides, cytosporones W (1) and X (2), along with eight known cytosporone derivatives [(±)-3-9], were isolated from mangrove endophytic fungus Diaporthe sp. ZJHJYZ-1. Compounds 1 and 2 were a pair of epimers, whose configuration of C-1 could mutually convert, causing racemization of the lactone ring. The planar structures of compounds were elucidated through detailed 1D, 2D NMR, and HR-ESI-MS analysis. ECD spectra comparison and modified Mosher ester method were applied to determine the absolute configuration of 1 and 2. In bioassays, (±)-3 exhibited promising inhibitory activities against Bacillus subtilis, Pseudomonas aeruginosa, and Penicillium italicum with MIC, respectively, for 12.5, 12.5, and 3.13 μM.