Macrolactamas derivadas de carboidratos: síntese e análise conformacional por métodos quanto-mecânicos

Abstract

In the first chapter of this work, the synthesis of two macrolactams with 11 and 15 members derived from D-galactose is described from the tri-n-butyltin hydride mediated radical cyclization of 2-iodobenzamides and two 3-(iodoacetamido)benzamides. Two macrolactams, resulting from 11- and 15-endo mode ciclization, were isolated, plus the uncyclized reduction products. In the second chapter, it is described the conformational analysis by theoretical calculations with semi-empirical (PM3) and DFT (B3LYP/6-311+G(d,p)) methods for these substracts, which pointed to 11-endo over 10-exo cyclization mode preference for insaturated allylic derivatives, and 10-exo over 11-endo, for insaturated cinnamylic compounds. The calculations also showed that methylenichydrogens abstraction reaction competes strongly with cyclization reaction. It is also described the performing of theoretical studies with the same methods for still unpublished cinnamylic, cinnamoylic and cinnamamidic different substracts, which pointed to 10-exo above 11-endo cyclization mode preference.