Cytotoxic tetronic acid derivatives from the mangrove endophytic fungus Hypomontagnella monticulosa YX702

• DOI: 10.1016/j.fitote.2023.105656
• Publication Date: 2023-08-19T17:10:41Z
• Authors: Yuxi Huang; Zanhong Chen; Meiying Huang; Kaixin Chen; Haisheng Liu; Juewen Liang; Yuting Liao; Jiayi Li; Liping Zhu; Bo Ding; Hongbo Huang; Yiwen Tao
• Keywords: Molecular Structure; Ascomycota; Antineoplastic Agents; 3. Good health

Three new tetronic acid derivatives, nodulisporacid A ethyl ester (3), isosporothric acid methyl ester (4), and (R)-3-(methoxycarbonyl)-2-methyleneundecanoic acid (5) were isolated from mangrove endophytic fungus Hypomontagnella monticulosa YX702, together with three known analogues nodulisporacid A (1), nodulisporacid A methyl ester (2), and dihydrosporothriolide (6). The structures of these new compounds were elucidated by analysis of NMR and HR-ESI-MS spectroscopic data. In addition, the absolute configuration of nodulisporacid A (1) was confirmed by single-crystal X-ray diffraction for the first time. Subsequently, the absolute configuration of compounds 2 and 3 were determined by chemical derivatization of nodulisporacid A (1). The absolute configuration of compound 4 and 5 were established by TDDFT ECD calculations. Compounds 1 and 2 exhibited cytotoxic activities against A549 and Hela cancer cell lines with the IC50 values between 5.64 and 8.14 μM.