- Anti-fertilization activity of a spirocyclic sesquiterpene isocyanide isolated from the marine sponge Geodia exigua and related compounds
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(-)-10-epi-Axisonitrile-3, a spirocyclic sesquiterpene isocyanide obtained from the marine sponge Geodia exigua, immobilized sperm of sea urchin and starfish to block fertilization at the minimum effective concentration of 0.4 μg/ml. On the other hand, fertilized eggs developed normally to the gastrula stage in the presence of a 250-times higher concentration of the isocyanide. Analysis by 31P NMR revealed an accumulation of phosphocreatine and a depletion of inorganic phosphate in the isocyanide-treated sperm, suggesting that (-)-10-epi-axisonitrile-3 inhibited the phosphocreatine shuttle participating in the high-energy phosphate metabolism, thereby immobilizing sperm to block fertilization. No analogs of (-)-10-epi-axisonitrile-3 containing different functionalities or isocyanides with different carbon skeleton exhibited such activity.
- Ohta, Emi,Uy, Mylene M.,Ohta, Shinji,Yanai, Mihoko,Hirata, Toshifumi,Ikegami, Susumu
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- Enantioselective Synthesis of Azetidines through [3 + 1]-Cycloaddition of Donor-Acceptor Aziridines with Isocyanides
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The enantioselective [3 + 1]-cycloaddition of racemic donor-acceptor (D-A) aziridines with isocyanides was first realized under mild reaction conditions using a chiral N,N′-dioxide/MgIIcomplex as catalyst, providing a facile route to enantioenriched exo-imido azetidines with good to excellent yield (up to 99%) and enantioselectivity (up to 94% ee). An obvious chiral amplification effect was observed in this system, and an explanation was elucidated based on the experimental investigation and X-ray crystal structure of the enantiomerically pure catalyst.
- Zhang, Fengcai,Sang, Xinpeng,Zhou, Yuqiao,Cao, Weidi,Feng, Xiaoming
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supporting information
p. 1513 - 1517
(2022/03/01)
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- Isocyanides as influenza A virus subtype H5N1 wild-type M2 channel inhibitors
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Basic bulky amines such as amantadine are well-characterized M2 channel blockers, useful for treating influenza. Herein we report our surprising findings that charge-neutral, bulky isocyanides exhibit activities similar to - or even higher than - that of amantadine. We also demonstrate that these isocyanides have potent growth inhibitory activity against the H5N1 virus. The -NH2 to -N≡C group replacement within current anti-influenza drugs was found to give compounds with high activities at low-micromolar concentrations. For example, a tenfold improvement in potency was observed for 1-isocyanoadamantane (27), with an EC50 value of 0.487 μm against amantadine-sensitive H5N1 virus as determined by both MTT and plaque-reduction assays, without showing cytotoxicity. Furthermore, the isocyanide analogues synthesized in this study did not inhibit the V27A or S31N mutant M2 ion channels, according to electrophysiology experiments, and did not exhibit activity against amantadine-resistant virus strains. Charge-neutral bulky isocyanides were found to exhibit antiviral activities similar to - or even higher than - that of amantadine. Moreover, we demonstrated that these isocyanides have potent growth inhibitory activity against the wild-type H5N1 virus. The NH2 to N≡C group replacement within current anti-influenza drugs was found to result in compounds with low-micromolar activities.
- Wu, Shuwen,Huang, Jing,Gazzarrini, Sabrina,He, Si,Chen, Lihua,Li, Jun,Xing, Li,Li, Chufang,Chen, Ling,Neochoritis, Constantinos G.,Liao, George P.,Zhou, Haibing,D?mling, Alexander,Moroni, Anna,Wang, Wei
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p. 1837 - 1845
(2015/11/10)
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- Multicomponent cascade cycloaddition involving tropone, allenoate, and isocyanide: A rapid access to a 7,6,5-fused tricyclic skeleton
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Multicomponent cascade cycloaddition of tropone, allenoate, and isocyanide has been disclosed. This method allows for the rapid construction of a highly unusual tricyclic skeleton in an efficient manner. The proposed transformation proceeds through [8 + 2 + 1] cycloaddition, [1,5]-H shift, and cyclization followed by an alkoxy group migration process.
- Jia, Shuanglong,Su, Shikuan,Li, Chunju,Jia, Xueshun,Li, Jian
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supporting information
p. 5604 - 5607
(2015/02/19)
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- Isocyanide-based multicomponent [2+2+1]-cycloaddition strategy to construct functionalized spirocyclic oxindoles
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Isocyanide-based three-component [2+2+1]-cycloaddition reactions from isocyanides, activated alkynes, and isatylidene malononitriles were investigated to provide a new access to spirocyclic oxindole with five-membered carbon rings. The displacement of isatylidene malononitrile with oxindolylideneacetate essentially results in opposite regioselectivity, which adds to its attractiveness. Georg Thieme Verlag Stuttgart ? New York.
- Jie, Haohua,Li, Jian,Li, Chunju,Jia, Xueshun
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supporting information
p. 2274 - 2278
(2012/10/29)
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- Syntheses of spirocyclic oxindole-butenolides by using three-component cycloadditions of isocyanides, allenoates, and isatins
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Spiro workflow! Efficient syntheses of spirocyclic oxindole-butenolides from readily available isocyanides, allenoates, and isatins are disclosed (see scheme; R1=alkyl, aryl; R2=halide, nitro, methoxy; PG=protecting group). This protocol also allows the insertion of carbon monoxide into organic molecules without the aid of a transition-metal catalyst after the hydrolysis process. Copyright
- Li, Jian,Liu, Yuejin,Li, Chunju,Jia, Xueshun
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supporting information; experimental part
p. 7409 - 7413
(2011/08/05)
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