Rhodomentosones A and B: Two Pairs of Enantiomeric Phloroglucinol Trimers from <i>Rhodomyrtus tomentosa</i> and Their Asymmetric Biomimetic Synthesis
Lu-Ming Deng, Lijun Hu, Yang-Ting-Zhi Bai, Jie Wang, Guan‐Qiu Qin, Qiao‐Yun Song, Jun‐Cheng Su, Xiao‐Jun Huang, Ren‐Wang Jiang, Wei Tang, Yao-Lan Li, Chuang‐Chuang Li, Wen‐Cai Ye, Ying Wang
Abstract
Rhodomentosones A and B (1 and 2), two pairs of novel enantiomeric phloroglucinol trimers featuring a unique 6/5/5/6/5/5/6-fused ring system were isolated from Rhodomyrtus tomentosa. Their structures with absolute configurations were elucidated by NMR spectroscopy, X-ray crystallography, and ECD calculation. The bioinspired syntheses of 1 and 2 were achieved in six steps featuring an organocatalytic asymmetric dehydroxylation/Michael addition/Kornblum–DeLaMare rearrangement/ketalization cascade reaction. Compounds 1 and 2 exhibited promising antiviral activities against respiratory syncytial virus (RSV).