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A s y m m e t r i c S y n t h e s i s o f ( + ) -P o l y o x a m i c A c i dAbstract: A short and efficient stereoselective synthesis of (+)-polyoxamic acid is described using an organocatalytic asymmetric Mannich reaction as the key step. The reaction proceeded in high yield and with excellent selectivity to establish two out of the three stereocenters present in (+)-polyoxamic acid. Additional steps include a diastereoselective reduction and ozonolysis of the furyl ring to generate the corresponding carboxylic acid.

A m i n o S u g a r s v i a A s y m m e t r i c O r g a n o c a t a l y t i c M a n n i c h R e a c t i o n s Abstract: An efficient biomimetic C 3 +C n entry to amino sugars and derivatives via a direct asymmetric organocatalytic Mannich methodology employing 2,2-dimethyl-1,3-dioxan-5-one as a dihydroxyacetone phosphate equivalent and N-PMP or N-Boc protected imines has been developed. The Mannich bases were obtained in high diastereo-and enantiomeric excesses (78% to >99% de, 81-98% ee) and were further elaborated using diastereoselective reduction protocols, as well as via diastereoselective direct reductive amination reactions.

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