title: Diastereo- and enantioselective construction of a bispirooxindole scaffold containing a tetrahydro-β-carboline moiety through an organocatalytic asymmetric cascade reaction.
abstract: The first catalytic asymmetric construction of a new class of bispirooxindole scaffold-containing tetrahydro-β-carboline moiety has been established through chiral phosphoric acid-catalyzed three-component cascade Michael/Pictet-Spengler reactions of isatin-derived 3-indolylmethanols, isatins, and amino-ester, which afforded structurally complex and diverse bispirooxindoles with one quaternary and one tetrasubstituted stereogenic centers in excellent stereoselectivities (all >95:5 diastereomeric ratio (d.r.), up to 98:2 enantiomeric ratio (e.r.)). This intriguing class of chiral bispirooxindoles integrated the two important structures of tetrahydro-β-carboline and bispirooxindole, both of them possessing significant bioactivities. This approach also combined the merits of asymmetric organocatalysis and multicomponent tandem reaction, which provided a unique strategy for the preparation of structurally rigid bispiro-architectures with concomitant creation of multiple quaternary stereogenic centers.
authors: School of Chemistry and Chemical Engineering, Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, Jiangsu Normal University, Xuzhou, 221116 (P.R. China), Fax: (+86) 516-83500065.
authors: Wei
authors: W
authors: Dai
authors: Han
authors: H
authors: Lu
authors: Xin
authors: X
authors: Li
authors: Feng
authors: F
authors: Shi
authors: Shu-Jiang
authors: SJ
authors: Tu
mesh_terms: D002243:Carbolines / Q000737:chemistry*; D002384:Catalysis; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D008958:Models, Molecular; D000078183:Oxindoles; D010756:Phosphoric Acids / Q000737:chemistry; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D002243:Carbolines; D007211:Indoles; D000078183:Oxindoles; D010756:Phosphoric Acids; D013141:Spiro Compounds; C022960:2-oxindole; C009804:tryptoline; C030242:phosphoric acid
keywords: asymmetric synthesis; bispirooxindoles; enantioselectivity; multicomponent reactions; organocatalysis