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Sumi S, Matsumoto K, Tokuyama H, Fukuyama T. Enantioselective total synthesis of aspidophytine. Org Lett 2003; 5:1891-3. [PMID: 12762679 DOI: 10.1021/ol034445e] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[structure: see text] An enantioselective total synthesis of aspidophytine is described. The indole fragment bearing a cis-alkene substituent was efficiently prepared through radical cyclization of a 2-alkenylphenylisocyanide followed by Sonogashira coupling of the generated 2-iodoindole derivative with a functionalized acetylene unit. After formation of the 11-membered cyclic amine, the aspidosperma skeleton and lactone ring were constructed to complete the total synthesis.
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Takahashi Y, Hayashi I, Tominari Y, Rikimaru K, Morohashi Y, Kan T, Natsugari H, Fukuyama T, Tomita T, Iwatsubo T. Sulindac sulfide is a noncompetitive gamma-secretase inhibitor that preferentially reduces Abeta 42 generation. J Biol Chem 2003; 278:18664-70. [PMID: 12637581 DOI: 10.1074/jbc.m301619200] [Citation(s) in RCA: 159] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Nonsteroidal anti-inflammatory drugs (NSAIDs) have been known to reduce risk for Alzheimer's disease. In addition to the anti-inflammatory effects of NSAIDs to block cylooxygenase, it has been shown recently that a subset of NSAIDs selectively inhibits the secretion of highly amyloidogenic Abeta42 from cultured cells, although the molecular target(s) of NSAIDs in reducing the activity of gamma-secretase for Abeta42 generation (gamma(42)-secretase) still remain unknown. Here we show that sulindac sulfide (SSide) directly acts on gamma-secretase and preferentially inhibits the gamma(42)-secretase activity derived from the 3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propanesulfonate-solubilized membrane fractions of HeLa cells, in an in vitro gamma-secretase assay using recombinant amyloid beta precursor protein C100 as a substrate. SSide also inhibits activities for the generation of Abeta40 as well as for Notch intracellular domain at higher concentrations. Notably, SSide displayed linear noncompetitive inhibition profiles for gamma(42)-secretase in vitro. Our data suggest that SSide is a direct inhibitor of gamma-secretase that preferentially affects the gamma(42)-secretase activity.
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Abstract
A convergent total synthesis of leustroducsin B (1), which is known to exhibit a variety of biological activities, was successfully carried out. Notable features of our synthesis include construction of the C8 stereocenter by lipase-mediated desymmetrization of meso-diol 4 (90.2% ee) and preparation of the C9-C11 anti-diol moiety by the addition of alkynylzinc reagent 20 to the aldehyde 19. Furthermore, a new diol protecting group, p-silyloxybenzylidene, was developed for the deprotection from densely functionalized substrates under weakly acidic conditions. The protecting group was easily removed in a two-step procedure ((HF)3.Et3N; AcOH-THF-H2O).
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229
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Fukuyama T, Kurosawa W, Kan T. An Efficient Synthesis of OpticallyActivetrans-2-Aryl-2,3-dihydrobenzofuran-3-carboxylicAcid Esters via C-H Insertion Reaction. Synlett 2003. [DOI: 10.1055/s-2003-39316] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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230
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Fukuyama T, Yamashita T, Tokuyama H. Stereoselective Formation ofa β-Lactam Fused Oxathiazepin: A Synthetic Approachto Eudistomins. Synlett 2003. [DOI: 10.1055/s-2003-38378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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231
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Yokoshima S, Ueda T, Kobayashi S, Sato A, Kuboyama T, Tokuyama H, Fukuyama T. Stereocontrolled total synthesis of (+)-vinblastine. PURE APPL CHEM 2003. [DOI: 10.1351/pac200375010029] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Stereocontrolled total synthesis of (+)-vinblastine (1) has been achieved using a novel radical-mediated indole synthesis developed in our laboratories. The isothiocyanate 18, prepared readily from quinoline 17, underwent a facile addition of the malonate anion to give 19. The o-alkenylthioanilide 19 was then converted to indole 20 by radical cyclization and protection. (−)-Vindoline (2) was prepared from this key intermediate 20 in a highly efficient manner. The indole core of the 11-membered intermediate 3 was constructed similarly from quinoline. The critical coupling reaction between 2 and the chloroindolenine derived from 3 proceeded with complete control of stereochemistry to give the desired product 66 in 97 % yield, which could be successfully converted to (+)-vinblastine (1).
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232
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Fukuyama T, Tokuyama H, Miyazaki T, Yokoshima S. A Novel Palladium-CatalyzedCoupling of Thiol Esters with 1-Alkynes. Synlett 2003. [DOI: 10.1055/s-2003-40861] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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233
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Kan T, Tominari Y, Morohashi Y, Natsugari H, Tomita T, Iwatsubo T, Fukuyama T. Solid-phase synthesis of photoaffinity probes: highly efficient incorporation of biotin-tag and cross-linking groups. Chem Commun (Camb) 2003:2244-5. [PMID: 13678222 DOI: 10.1039/b306970b] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A benzophenone cross-linking group and a biotin-tag hybrid, resin 1a, attached to our novel resin 2 was readily converted to the photoaffnity probe 20 by condensation with the ligand carboxylic acid 19 and cleavage from the resin without purification.
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234
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Fukuyama T. Total Synthesis of Nitrogen-Containing Natural Products and Development of Synthetic Methodology. J SYN ORG CHEM JPN 2003. [DOI: 10.5059/yukigoseikyokaishi.61.620] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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235
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Hashinokuchi M, Che DC, Watanabe D, Fukuyama T, Koyano I, Shimizu Y, Woelke A, Kasai T. Single |JΩMJ〉 state-selection of OH radicals using an electrostatic hexapole field. Phys Chem Chem Phys 2003. [DOI: 10.1039/b305381d] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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236
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Suzuki M, Kambe M, Tokuyama H, Fukuyama T. Facile construction of N-hydroxybenzazocine: enantioselective total synthesis of (+)-FR900482. Angew Chem Int Ed Engl 2002; 41:4686-8. [PMID: 12481326 DOI: 10.1002/anie.200290016] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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237
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Kan T, Fujiwara A, Kobayashi H, Fukuyama T. Efficient macrocyclization by means of 2-nitrobenzenesulfonamide and total synthesis of lipogrammistin-A. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)00626-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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238
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Endo A, Yanagisawa A, Abe M, Tohma S, Kan T, Fukuyama T. Total synthesis of ecteinascidin 743. J Am Chem Soc 2002; 124:6552-4. [PMID: 12047173 DOI: 10.1021/ja026216d] [Citation(s) in RCA: 224] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The total synthesis of ecteinascidin 743 (1), an extremely potent antitumor agent, has been accomplished. The synthesis features Ugi's 4CC reaction, intramolecular Heck reaction, phenol-aldehyde cyclization, and acid-induced intramolecular sulfide formation.
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239
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Nishiura H, Matsuda K, Kikuchi T, Fukuyama T. Phenomenological analysis of lepton and quark mass matrices. Int J Clin Exp Med 2002. [DOI: 10.1103/physrevd.65.097301] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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240
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Gargiulo D, Musser SS, Yang L, Fukuyama T, Tomasz M. Alkylation and Crosslinking of DNA by the Unnatural Enantiomer of Mitomycin C: Mechanism of the DNA-Sequence Specificity of Mitomycins. J Am Chem Soc 2002. [DOI: 10.1021/ja00142a002] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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241
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Schmid G, Fukuyama T, Akasaka K, Kishi Y. Synthetic studies on polyether antibiotics. 4. Total synthesis of monensin. 1. Stereocontrolled synthesis of the left half of monensin. J Am Chem Soc 2002. [DOI: 10.1021/ja00495a064] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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242
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243
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Fukuyama T, Lin SC, Li L. Facile reduction of ethyl thiol esters to aldehydes: application to a total synthesis of (+)-neothramycin A methyl ether. J Am Chem Soc 2002. [DOI: 10.1021/ja00175a043] [Citation(s) in RCA: 257] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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244
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245
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246
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Nakatsubo F, Fukuyama T, Cocuzza AJ, Kishi Y. Synthetic studies toward mitomycins. 2. Total synthesis of dl-porfiromycin. J Am Chem Soc 2002. [DOI: 10.1021/ja00466a089] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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247
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248
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Fukuyama T, Akasaka K, Karanewsky DS, Wang CLJ, Schmid G, Kishi Y. Synthetic studies on polyether antibiotics. 6. Total synthesis of monensin. 3. Stereocontrolled total synthesis of monensin. J Am Chem Soc 2002. [DOI: 10.1021/ja00495a066] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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249
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250
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Fukuyama T, Wang CLJ, Kishi Y. Synthetic studies on polyether antibiotics. 5. Total synthesis of monensin. 2. Stereocontrolled synthesis of the right half of monensin. J Am Chem Soc 2002. [DOI: 10.1021/ja00495a065] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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