Novel rearranged acetophenone derivatives possessing diverse architectures from the leaves of Melicope ptelefolia

• Published in: Tetrahedron Vol. 75; no. 52; pp. 130784 - 130790
• Main Authors: Xu, Jin-Fang, Han, Chao, Xue, Gui-Min, Wang, Xiao-Bing, Luo, Jun, Yang, Ming-Hua, Luo, Jian-Guang, Kong, Ling-Yi
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 27.12.2019; Elsevier
• Subjects: Acetophenone derivatives; Chemistry; Chemistry, Organic; Melicope ptelefolia; Multidrug resistance; Natural products; Physical Sciences; Rearrangement; Science & Technology; Natural products; Acetophenone derivatives; Multidrug resistance; Melicope ptelefolia; Rearrangement; CORE; STEREOISOMERS; CHROMENES; CONSTITUENTS
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/j.tet.2019.130784

Melicolones C–K (1–9), nine acetophenone derivatives with three unprecedented architectures, were characterized from the leaves of Melicope ptelefolia. Among them, melicolone C (1) was a novel acetophenone analogue possessing a highly rearranged spiro skeleton. Melicolones D-F (2–4) were three novel acetophenone congeners bearing unusual octalactone ring. Melicolones G-K (5–9) were five new prenylated acetophenone derivatives featuring a 9-oxatricyclo [3.2.1.13, 8]nonane core. Their structures were established by extensive spectroscopic analysis and ECD spectra. These different structures were presumably derived from the same precursor via three major biosynthetic pathways. Compounds 5–9 exerted moderate effects to reverse multidrug-resistance in MCF-7/ADR cells with reversal fold values ranging from 6.2 to 13.3. [Display omitted] •Nine acetophenone derivatives represented three different carbon skeletons were isolated from Melicope ptelefolia.•1 possessed a rearranged spiro skeleton. 2–4 had an octalactone ring. 5–9 featured a 9-oxatricyclo [3.2.1.13,8]nonane core.•Compounds 5–9 exhibited moderate effects to reverse multidrug-resistance with MCF-7/ADR cells.