Premium
Improved Synthesis and Reaction of 11‐Chloroneocryptolepines, Strategic Scaffold for Antimalaria Agent, and Their 6‐Methyl Congener from Indole‐3‐carboxylate
Author(s) -
Wang Li,
Lu WenJie,
Odawara Tomohito,
Misumi Ryuhei,
Mei ZhenWu,
Peng Wei,
ElSayed Ibrahim ElTantawy,
Inokuchi Tsutomu
Publication year - 2014
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.1617
Subject(s) - chemistry , indole test , moiety , carboxylate , quinoline , ring (chemistry) , stereochemistry , congener , methylation , nucleophile , medicinal chemistry , combinatorial chemistry , organic chemistry , catalysis , biochemistry , gene
Various 11‐chloro‐5‐methyl‐5 H ‐indolo[2,3‐ b ]quinolines (neocryptolepines) with different substituents on the quinoline ring, key intermediates for antimalaria agents, are prepared from the substituted N ‐methylanilines, easily accessible by the N ‐methylation of anilines, and indole‐3‐carboxylate as a counterpart. This protocol is benign in terms of the reduced number of steps to reach the target, compared with the known method using anilines, and easy product purification . Alternatively, their 6‐methyl congener is prepared by N ‐methylation of the indole moiety of 2‐arylaminoindole‐3‐carboxylate followed by successive cyclization and chlorination . 11‐Chloroneocryptolepines are found more reactive than their 6‐methyl congener in the nucleophilic substitution at the C11 position.