Two polycyclic polyprenylated acylphloroglucinols, garcimulins A and B ((+/-)-1 and 2), including a pair of enantiomers with the unique caged tetracyclo[18.104.22.168(1,5).0(9,13)]tridecane skeleton were isolated from Garcinia multiflora. Their structures and absolute configurations were determined by extensive analysis of spectroscopic data and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 exhibited cytotoxic activities against five human cancer cell lines in vitro (IC50 3.42-13.23 mu M). The acidification of lysosomes in HeLa cell was obviously affected by compound 2.
Scientific and Technological Planning Project of Guizhou [QKH-NZ (2011) 3002]
; Modernization of Traditional Chinese Medicine [QKH-NZ (2011) 5085]
; Talent Base Construction Funds (Starting Fund) 
1.Key Lab Chem Nat Prod Guizhou Prov, Guiyang 550002, Peoples R China 2.Chinese Acad Sci, Guiyang 550002, Peoples R China 3.Chinese Acad Sci, Inst Genet & Dev Biol, State Key Lab Mol Dev Biol, Beijing 100101, Peoples R China 4.Chinese Acad Sci, Kunming Inst Bot, State Key Lab Phytochem & Plant Resources West Ch, Kunming 650201, Peoples R China