Synthesis of new squaramide backbone peptidomimetics catalysts

Organocatalysis, i.e., the use of organic molecules for the construction of new chemical bonds in the absence of metals, is a ramification of asymmetric catalysis which has been rapidly developed in the last decade. 1 In order to have high enantioselectivity levels, the choose of the chiral catalyst should be planned very carefully. In the search for new organocatalyst for asymmetric addition, combinatorial chemistry has been applied and has shown to be very efficient. Due to high efficiency and versatility of amino acids and peptides as organocatalyst, the search for new synthetic methodologies to achieve them is of high importance. In particular, the study of Ugi multicomponent reaction is very interesting due to atom economy and high variety of chiral blocks which can be easily achieved through the use of this reaction. 2 Herein, we report the synthesis of new peptoid catalysts using Ugi 4-CR and their insertion on squaramide template, in order to be used as hydrogen bond activators in 1,6-Michael additions.