Ku Y.-L.Rao G.V.Chen C.-H.Wu C.JIH-HWA GUHSHOEI-SHENG LEE2021-06-022021-06-0220030018019Xhttps://www.scopus.com/inward/record.uri?eid=2-s2.0-0037254839&doi=10.1002%2fhlca.200390068&partnerID=40&md5=b5c699db590aadd267d53617cc7afff4https://scholars.lib.ntu.edu.tw/handle/123456789/564883Bio-assay-guided fractionation of the CHCl3-soluble extract from the leaves of Viburnum aboricolum led to the isolation of a novel secobetulinic acid 3,4-lactone, viburolide (=(6β)-4,6-dihydroxy-3,4-secolup-20(29)-ene-3,28-dioic acid 3,4-lactone; 1). This is the first lupane-type compound possessing such a lactone skeleton from natural products. Its structure was elucidated by spectral analysis and comparison with 6-dehydroxy-20,29-dihydroviburolide (6) prepared from benzyl betulinate (2). Compound 6 was found to inhibit androgen-independent human prostate cancer cells (PC-3) with an 1C50 of 12.3 μM.[SDGs]SDG3Bioassay; Fractionation; Halogen compounds; Spectrum analysis; Synthesis (chemical); Tumors; Chloroform; Organic acids; 6 hydroxy 20,29 dihydroviburolide; benzyl derivative; betulic acid; lactone derivative; plant extract; unclassified drug; viburolide; article; bioassay; cancer cell; drug structure; drug synthesis; IC 50; priority journal; spectroscopy; structure analysis; Viburnum; Viburnum aboricolumjournal article10.1002/hlca.2003900682-s2.0-0037254839