A simple approach to multifunctionalized N1-alkylated 7-amino-6-azaoxindole derivatives using their in situ stabilized tautomer form

被引：4

作者：

Tzvetkov, Nikolay T. ^{[1
]}

Neumann, Beate ^{[2
]}

Stammler, Hans-Georg ^{[2
]}

Antonov, Liudmil ^{[3
]}

机构：

[1] Univ Bonn, Inst Pharmaceut, Immenburg 4, D-53121 Bonn, Germany

[2] Univ Bielefeld, Dept Chem, Univ Str 25, D-33615 Bielefeld, Germany

[3] Bulgarian Acad Sci, Ctr Phytochem, Inst Organ Chem, Acad G Bonchev Str,Bl 9, BU-1113 Sofia, Bulgaria

来源：

TETRAHEDRON | 2016年 / 72卷 / 41期

基金：

瑞士国家科学基金会;

关键词：

Amino-azaindole; Reductive cyclization; N-Alkylation; Synthesis; Tautomers; SPONGE KIRKPATRICKIA-VARIALOSA; DENSITY FUNCTIONALS; DESIGN; ALKALOIDS; 5-AZAINDOLES; 7-AZAINDOLES; REACTIVITY; INHIBITORS;

D O I：

10.1016/j.tet.2016.08.055

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

A simple approach for the synthesis of multifunctionalized N1-alkyl 7-amino-6-azaoxindole derivatives was developed and investigated. Formation of 5-amino- and 7-amino-6-aza-2-oxindoles 12a and 13a, respectively, was achieved using an intramolecular reductive cyclization as a key step. Subsequent alkylation of the pyrrole N1 atom in 12a led to the desired N1-alkylated compounds 22a-24 comprising different functionalities. Alkylation of 5-amino-substituted regioisomer 13a under the same conditions as used for 12a did not resulted in N1-alkylated products. To find a plausible explanation for the observed differences in reactivity, we investigated the possible tautomers of 12a and 13a and the distribution of their neutral and ionized forms in a gas phase. The relevant physicochemical properties of compounds 12a and 23 were determined. (C) 2016 Elsevier Ltd. All rights reserved.

引用

页码：6455 / 6466

页数：12