Stereoselective organocatalyzed glycosylations - thiouracil, thioureas and monothiophthalimide act as Bronsted acid catalysts at low loadings.

ABSTRACT: Thiouracil catalyzes stereoselective glycosylations with galactals in loadings as low as 0.1 mol%. It is proposed that in these glycosylations thiouracil, monothiophthalimide, and the previously reported catalyst, Schreiner's thiourea, do not operate via a double H-bonding mechanism but rather by Brønsted acid/base catalysis. In addition to the synthesis of 2-deoxyglycosides and glycoconjugates, we report the first organocatalytic synthesis of 1,1'-linked trehalose-type sugars.

SUBMITTER: Bradshaw GA 

PROVIDER: S-EPMC6334493 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature