118(P-70) 血管新生阻害剤epoxyquinol AおよびBの合成(ポスター発表の部)
スポンサーリンク
概要
- 論文の詳細を見る
Epoxyquinols A (1) and B (2), heptacyclic pentaketide dimmers isolated from an uncharacterized fungus by Osada and co-workers, exhibit potent antiangiogenic activity. Its complicated molecular architecture as well as the intriguing biological activity has attracted considerable attention of synthetic chemists and several total syntheses of 1 and 2 through oxidative dimerization of pentaketide monomer 3 (a biosynthetic precursor of the epoxyquinols) have been reported so far. In this symposium, we report a new enantioselective synthesis of 3 using the Evans asymmetric aldol reaction and its conversion to epoxyquinols A and B. Evans' asymmetric syn-aldol reaction of (S)-4-benzyl-3-(4-pentenoyl)-2-oxazolidinone (4) with 3-methyl-2-butenal (5) was followed by reductive removal of the chiral auxiliary to give diol 13. After protection of the diol as bis-TBS ether, the monosubstituted double bond of the resulting diene 14 was selectively oxidized by the Wacker oxidation. Ozonolysis of the remaining double bond of the oxidation product gave keto aldehyde 16, which was then cyclized by intramolecular aldol condensation to afford a cyclohexenone intermediate (18). Stereoselective nucleophilic epoxidation of enone 18 was followed by double bond formation and bromination to give a vinyl bromide (21), which was subjected to the Stille coupling reaction with tributyl(1-propenyl)stannane (Pd_2dba_3, Ph_3As, toluene) to furnish the key intermediate (3) after removal of the TBS-protecting groups (HF・Py, THF). Finally, TEMPO-mediated oxidation of 3 followed by Diels-Alder dimerization of the resulting oxidation product mixture in 40% aq. methanol gave 1 and 2. Thus, the enantioselective total synthesis of 1 and 2 was accomplished in 13 steps from 4.
- 2004-10-01
著者
関連論文
- 88(P-12) タバコ野火病原因菌由来の非選択的植物毒素tabtoxinine-β-lactamの合成研究(ポスター発表の部)
- A309 非選択的植物病原菌毒素 tabtoxinine-β-lactam の合成研究
- A308 イネいもち病菌毒素 pyricuol の合成研究
- B223 植物ホルモンアブシジン酸、ジャスモン酸のシクロプロパン化アナログの調製
- P-53 オーキシン様発根促進物質Pteridic acid AおよびBの合成(ポスター発表の部)
- A106 ミカンヒメコナカイガラムシの性フェロモンの合成
- C213 コナカイガラムシ(Pseudococcus viburni)の性フェロモンの合成
- P-41 マクロテトラオリド抗生物質polynactin類のアナログ創製研究(ポスター発表の部)
- Rhizoglyphus setosusの性フェロモン(一般講演)(第11回日本ダニ学会大会講演要旨(福井大会))
- 118(P-70) 血管新生阻害剤epoxyquinol AおよびBの合成(ポスター発表の部)
- 12 Bacilosarcin AおよびBの全合成(口頭発表の部)
- P-22 抗ストレス性潰瘍物質Al-77-Bおよびその関連物質の合成研究(ポスター発表の部)
- 生態相関物質の合成研究 : 昆虫フェロモンを中心として
- 88(P-45) Pamamycin-607の合成研究(ポスター発表の部)
- P-47 Platensimycinの全合成研究(ポスター発表の部)
- A208 イネいもち病菌の生産する毒素ピリキュラリオールはラセミ体であった(天然物化学,一般講演要旨)
- 9C02 新規骨格植物成分echinopine類の合成研究(天然物化学,一般講演要旨)
- C307 イネいもち病菌の生産するサリチルアルデヒド型毒素類の合成研究(代謝,分析,動態,合成プロセス,グリーンケミストリー,一般講演要旨)
- B208 抗ガン物質JBIR-23の合成研究(生物活性 検定法,一般講演要旨)
- P-43 Thiersinine AおよびBの全合成研究(ポスター発表の部)