DUGi

Aproximacions a la síntesi estereoselectiva de noves heteroarilglicines

http://dugi.udg.edu/item/http:@@@@hdl.handle.net@@10256@@4701

L’objectiu principal de la present tesi doctoral ha consistit fonamentalment en la síntesi de noves heteroarilglicines òpticament pures. Amb aquesta idea s’han desenvolupat dues estratègies diferents: síntesi estereoselectiva utilitzant auxiliars quirals i síntesi estereocontrolada utilitzant aldehids quirals derivats d’ L-serina com a "building-blocks". Així doncs, per a la primera estratègia s’han dissenyat i sintetitzat els dos nous auxiliars quirals del tipus imidazolidin-2-ona 111 i 135 utilitzant L-fenilalanina i L-serina respectivament com a materials de partida òpticament purs. Davant els problemes detectats en la síntesi d’a-aminoàdics mitjançant síntesi asimètric, s’ha canviat d’estratègia i s’ha utilitzat una síntesi estereocontrolada utilitzant aldehids quirals obtinguts a partir d’L-serina.

The main target of the present PHD work was the synthesis of optically pure novel heteroarylglycines. With this aim, two different strategies were developed: stereoselective synthesis using chiral auxiliaries, and stereocontrolled synthesis using chiral aldehydes derived from L-serine as "building-blocks". For the first strategy, two novel imidazolidine-2-one chiral auxiliaries of type 111 and 135 were designed and prepared. As optically pure starting materials, L-phenylalanine and L-serine were used respectively. Unfortunately, the stereoselective synthesis of a-aminoacids using these chiral auxiliaries did not afford the desired results, and, in almost all cases, unreacted starting material was recovered. In a second approach, an stereocontrolled synthesis using chiral aldehydes derived fom L-serine was developed.

Universitat de Girona