35023-80-4Relevant articles and documents
Addition of organometallic reagents to N-glycosyl nitrones. Enantioselective syntheses of (+)-(R)- and (-)-(S)-zileuton
Basha,Henry,McLaughlin,Ratajczyk,Wittenberger
, p. 6103 - 6106 (1994)
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Reversal of Stereoselectivity in Cycloadditions of Five-Membered Cyclic Nitrones Derived from Hexoses
Malatinsky, Tomá?,Spi?áková, Mária,Babjak, Matej,Doháňo?ová, Jana,Marek, Jaromír,Moncol, Ján,Fischer, Róbert
, p. 1086 - 1098 (2017/02/23)
Two five-membered cyclic nitrones derived from hexoses, a newly synthesized d-allo-configured nitrone and an already known d-talo-configured nitrone, have been examined in 1,3-dipolar cycloaddition reactions with vinyl acetate, allyl benzoate, methyl acrylate, acrylonitrile, and vinylene carbonate. The reactions of the d-allo-configured nitrone proceeded preferentially through the expected exo-anti transition state, but all the cycloadditions of the d-talo-configured nitrone surprisingly showed high exo-syn selectivity. This reversal of stereoselectivity has been explained by 3D analysis of the preferred conformations of the nitrones, obtained from X-ray data. The structures were further inspected using CONFLEX, PM5, and DFT calculations. All these methods revealed that the dioxolane substituents attached to C-5 of both nitrones had opposite spatial locations.
Spirocyclopropyl pyrrolidines as a new series of α-l-fucosidase inhibitors
Laroche, Christophe,Behr, Jean-Bernard,Szymoniak, Jan,Bertus, Philippe,Schuetz, Catherine,Vogel, Pierre,Plantier-Royon, Richard
, p. 4047 - 4054 (2007/10/03)
Polyhydroxy 4-azaspiro[2.4]heptane derivatives (spirocyclopropyl iminosugars) were prepared in four to six steps from readily available protected aldoses. The key step of the reaction sequence involves a titanium-mediated aminocyclopropanation of glyconon