Total synthesis and anticancer activities of (-)- and (+)-thespesone.
The natural p-naphthoquinone (-)-thespesone 1 and its (+)-enantiomer were synthesized for the first time by bisacylation of a 5-lithiodihydrobenzofuran 2' with 4-methyl-3-tert-butoxycyclobut-3-ene-1,2-dione 3. The racemate of the required 2-arylpropan-1-ol precursor 10 was kinetically resolved by an enzyme-catalyzed acetylation exclusively of the (S)-enantiomer. Saponification of this acetate mediated by the same enzyme, porcine pancreas lipase (PPL), afforded the (S)-2-arylpropan-1-ol in 96% ee. Its unreacted (R)-enantiomer could be obtained with 77% ee. (-)-(S)-thespesone was far more efficacious against a panel of six cancer cell lines including multiresistant ones than its (+)-enantiomer and also when compared to thymoquinone, an established natural antitumoral p-quinone from Nigella sativa. Unlike the latter, (-)-thespesone was well tolerated by nonmalignant fibroblasts.
Breyer
Sandra
S
Organic Chemistry Laboratory, University of Bayreuth, 95440 Bayreuth, Germany.
Effenberger-Neidnicht
Katharina
K
Schobert
Rainer
R
D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D006367:HeLa Cells; D006801:Humans; D015394:Molecular Structure; D009285:Naphthoquinones / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
D000970:Antineoplastic Agents; D009285:Naphthoquinones; C121004:thespesone