Summary: | 碩士 === 國立彰化師範大學 === 化學系 === 103 === Calanquinone A was isolated from the stems of Calanthe arisanensis, Calanquinone A showed potentcytotoxicity (EC50 &;lt; 0.5 lg/mL) against lung (A549), prostate (PC-3 and DU145), colon (HCT-8), breast(MCF7), nasopharyngeal (KB), and vincristine-resistant nasopharyngeal (KB-VIN) cancer cell. So we undertook the synthesis of Calanquinone A and optically pure Calanquinone A dimer 30.
Triflate compound 22 was prepared from the commercially available 3,4,5- Trimethoxybenzaldehyde by Baeyer-Villiger oxidation and triflation.Phenylacetylene compound 10 was synthesized from 2,4,5- Trimethoxybenzaldehyde by Corey-Fuchs reaction. In addition, the precursor 23 was prepared via Sonogashira coupling reaction of 22 and 10. Reduction of 23 was achieved by palladium catalyzed hydrogenation. Further, treated by AgO with HNO3 to afford benzoquinones 26. And use of Lewis acid cyclization.Selective demethylation with TMSI, and followed by oxidation to afford Calanquinone A.Finally, using radical oxidation of Calanquinone A with palladium metal provided (±)- Calanquinone A dimer 32. The resolution of the racemic Calanquinone A dimer 30 was performed with chiral agent, and then followed by deprotection to get optically pure Calanquinone A dimer 30.
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