- One-pot α-amidosulfone-mediated variation of the pictet-Spengler tetrahydroisoquinoline synthesis, suitable for amide-type substrates
-
The development of Pictet-Spengler reactions from amide substrates is a challenging problem. We report here that the reaction between amide-type compounds (including carbamates, amides, ureas and diketopiperazines), aldehydes and p-toluenesulfinic acid constitutes an efficient method for the preparation of tetrahydroisoquinolines or pyrazino-[2,1-b]isoquinolines. Unlike previously known methods, this one-pot Pictet-Spengler protocol avoids the need for strong Lewis or Br?nsted acid catalysts.
- Arroyo, Francisco J.,López-Alvarado, Pilar,Ganesan,Menéndez, J. Carlos
-
supporting information
p. 5720 - 5727
(2014/11/07)
-
- Synthesis of 1,3-disubstituted symmetrical/unsymmetrical ureas via Cs2CO3-catalyzed transamination of ethylene carbonate and primary amines
-
Cs2CO3-catalyzed transamination of primary amines and ethylene carbonate proceeds to form 1,3-disubstituted symmetrical/unsymmetrical ureas in excellent yields. The effect of different reaction parameters such as influences of bases, temperature, and reaction time were investigated for the title reaction.
- Jagtap, Sachin R.,Patil, Yogesh P.,Panda, Anil G.,Bhanage, Bhalchandra M.
-
experimental part
p. 2093 - 2100
(2009/10/17)
-
- Azotized emetine analogues: synthesis and evaluation of the anti-amebic and anti-tumoral action of aza-3 emetine and attempted synthesis of aza-2 emetine
-
The synthesis of the N,N-bis-(acetylhomoveratrylamido)-1-hydroxymethyl and 1-carboxypropylamines (III a) and (III b) is described. Until now, these molecules could not been cyclized to the corresponding isoquinoline compounds. An attempted synthesis of 3-azaemetine by condensing homoveratrylamine with acetonedicarboxylic acid or its esters did not yield the expected diamide (XIV). However, by subjecting 1,3-bis-(1,2,3,4-tetrahydro-6,7-dimethoxy-1-isoquinolyl)acetone (XV) to a reducing aminoalkylation, one obtained the corresponding ethylamino derivative (XVI) which could be cyclized through Mannich reaction to give 3-azaemetine. The pharmacological screening showed 3-azaemetine to be less toxic than emetine in the mouse and without antiamebic and antitumor activity against P 388 Leukaemia in the mouse (25).
- Gilbert,Gansser,Viel,Cavier,Chenu,Hayat
-
p. 237 - 252
(2007/10/05)
-