481656-21-7Relevant articles and documents
Enantioselective total synthesis of (+)-stachyflin: A potential anti-influenza a virus agent isolated from a microorganism
Sakurai, Junji,Kikuchi, Takuya,Takahashi, Ohgi,Watanabe, Kazuhiro,Katoh, Tadashi
, p. 2948 - 2957 (2011/06/26)
A novel and potent hemagglutinin inhibitor, (+)-stachyflin, was efficiently synthesized in an enantioselective manner starting from the (+)-5-methyl-Wieland-Miescher ketone. The synthetic method features a BF 3·Et2O-induced cascade epoxide-opening/ rearrangement/cyclization reaction tostereoselectively construct the requisite pentacyclic ring system in one step. In order to rationalize the mechanism of the cascade reaction, quantum chemical calculations of the possible intermediary carbocations and transition states in the model synthesis were carried out. An alternative approach to synthesize (+)-stachyflin by employing a similar cascade reaction was also described. A potential anti-influenza A virus agent, (+)-stachyflin, a novel hemagglutinin inhibitor, has been synthesized in an enantioselective manner for the first time starting from (+)-5-methyl-Wieland- Miescher ketone. The method features a BF3·Et 2O-induced cascade epoxide-opening/rearrangement/cyclization reaction to construct the requisite pentacyclic ring system in one step.
Highly efficient total synthesis of the marine natural products (+)-avarone, (+)-avarol, (-)-neoavarone, (-)-neoavarol and (+)-aureol
Sakurai, Junji,Oguchi, Takamasa,Watanabe, Kazuhiro,Abe, Hideki,Kanno, Syu-Ichi,Ishikawa, Masaaki,Katoh, Tadashi
, p. 829 - 837 (2008/12/23)
Biologically important and structurally unique marine natural products avarone (1), avarol (2), neoavarone (3), neoavarol (4) and aureol (5), were efficiently synthesized in a unified manner starting from (+)-5-methyl-Wieland- Miescher ketone 10. The synthesis involved the following crucial steps: i) Sequential BF3·Et2O-in-duced rearrangement/ cyclization reaction of 2 and 4 to produce 5 with complete stereoselectivity in high yield (2 → 5 and 4 → 5); ii) strategic salcomine oxidation of the phenolic compounds 6 and 8 to derive the corresponding quinones 1 and 3 (6 → 1 and 8 →3); and iii) Birch reductive alkylation of 10 with bromide 11 to construct the requisite carbon framework 12 (10 + 11 → 12). An in vitro cytotoxicity assay of compounds 1-5 against human histiocytic lymphoma cells U937 determined the order of cytotoxic potency (3 > 1 > 5 > 2 > 4) and some novel aspects of structure-activity relationships.
Highly Improved Synthesis of (+)-Aureol via (-)-Neoavarone and (-)-Neoavarol, by Employing Salcomine Oxidation and Acid-Induced Rearrangement/Cyclization Strategy
Suzuki, Akiyuki,Nakatani, Mari,Nakamura, Masahiko,Kawaguchi, Keiko,Inoue, Munenori,Katoh, Tadashi
, p. 329 - 332 (2007/10/03)
A short and efficient synthesis of (+)-aureol (1), a structurally novel and biologicaly important marine natural product, was achieved starting with readily available (+)-Wieland-Miescher ketone analogue 7 via (-)-neoavarone (10) and (-)-neoavarol (11). The method features salcomine oxidation of the phenol derivative 9 to deliver 10 and BF3*OEt2-induced rearrangement/cyclization reaction of 11 to produce 1 as the crucial steps. The improvement biomimetic synthesis required only 9 steps and proceeds in 31 percent overall yield.
A New Strategy toward the Total Synthesis of Stachyflin, A Potent Anti-Influenza A Virus Agent: Concise Route to the Tetracyclic Core Structure
Nakatani, Mari,Nakamura, Masahiko,Suzuki, Akiyuki,Inoue, Munenori,Katoh, Tadashi
, p. 4483 - 4486 (2007/10/03)
(Matrix Presented) A new strategy directed toward the total synthesis of stachyflin, a potent and novel anti-influenza A virus agent isolated from a microorganism, has been presented through the enantioselective synthesis of the tetracyclic core structure. The synthetic method features a BF3·Et2O-induced domino epoxide-opening/rearrangement/cyclization reaction as the key step.
