| Summary: | 碩士 === 中國文化大學 === 應用化學研究所 === 94 === Pulveraven A and pulveraven B are two new compounds isolated form Pulveroboletus ravenelii and showed inhibitiory activity on carcinogen-induced preneoplastic lesion formation with mouse mammary organ culture. In this thesis, total synthesis of pulveraven A and pulveraven B were investigated.
1,4-Dioxaspiro[4,5]decan-2-one was chosen as the starting material, which reacted with N-bromosuccinimide and benzoyl peroxide by radical reaction to give a bromide (PA-1). The bromide reacted with triphenylphosphine by substitution reaction to give a salt (PA-2). The salt reacted with 1,4-diazabicyclo[2,2,2]octane (DABCO) to become a ylide, and the ylide reacted with benzaldehyde by Wittig reaction to give two isomers PA-3A and PA-3B. tert-Butyl benzoylacetate (PA-4) reacted with NaH to give a carbanion, which reacted with PA-3B by nucleophilic addition and cyclization to give PA-5. Treatment of this compound with TBDMSCl will give PA-6. After reacting with methyl phenylacetate by nucleophilic addition, compound PA-6 will give two diastereomers, PA-7A and PA-7B, which will be converted to PA-8A and PA-8B by reduction of NaBH3CN. Finally, treatment of compounds PA-8A and PA-8B with TBAF will give (±)-pulveraven A (PA-9A) and (±)-pulveraven B (PA-9B).
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