Resumo: Em 2012, Nogawa e colaboradores isolaram as espirotoamidas A e B e em 2017,
Yang e colaboradores isolaram as espirotoamidas C e D, quatro novos policetideos
contendo aneis de 6,6-espirocetal com dois efeitos anomericos, alem de uma amida
terminal. Estes compostos foram isolados a partir de uma fracao do metabolito
microbiano de Streptomyces griseochromogenes JC82-1223. A estrutura da
espirotoamida A (44) consiste em um total de 9 centros estereogenicos, sendo que
para um deles, a estereoquimica e desconhecida. Para esta tese, demos inicio a
preparacao da espirotoamida A, visando sua obtencao alem da confirmacao do centro
estereogenico desconhecido. Ate o presente momento, nos sintetizamos o esqueleto
C(7)-C(20) de forma altamente regio-, diastereo- e enantiosseletiva, empregando
como etapas determinantes a reacao aldolica com inducao do tipo 1,5-anti e a inducao
de Mukaiyama, fazendo uso de ¿¿-metil-¿À-hidroxicetonas e aldeidos, alem da
preparacao do fosfonato que contem o esqueleto C(1)-C(5) Ver menos

Abstract: In 2012, Nogawa and coworkers isolated spirotoamides A and B and in 2017, Yang
and collaborators isolated spirotoamides C and D, four new polyketides containing 6,6-
spirocetal rings with two anomeric effects, in addition to a terminal amide. These
compounds were isolated from a fraction of the microbial metabolite of Streptomyces
griseochromogenes JC82-1223. The structure of spirotoamide A (44) consists of a total
of 9 stereogenic centers, and for one of them, stereochemistry is unknown. For this
thesis, we started the preparation of spirotoamide A, aiming to obtain it beyond the
confirmation of the unknown stereogenic center. Up to the present moment, we have
synthesized the C(7)-C(20) skeleton in a highly regal, diastereo- and enantioselective
way, employing the aldol reactions using á-methyl-â-hydroxy ketones and aldehydes,
in addition to the preparation of the phosphonate that contains the C(1)-C(5) skeleton Ver menos