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Substituted Imidazoline Synthesis: A Diastereo- and Enantioselective aza-Henry Route to a Human Proteasome Modulator.

ABSTRACT: The first enantio- and diastereoselective synthesis of Tepe's human proteasome modulator is described. Routes to this and other highly substituted chiral imidazolines generally produce racemic material. Key to the route disclosed here is a gram-scale anti-selective aza-Henry reaction of an α-alkyl α-nitro ester nucleophile, catalyzed by a Bis(Amidine) [BAM] chiral proton complex, delivering the key intermediate in high yield as a single stereoisomer. The adduct is reduced to the amino ester and converted to an imidazoline.

SUBMITTER: Sprague DJ

PROVIDER: S-EPMC8627105 | biostudies-literature |

REPOSITORIES: biostudies-literature

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