<i>N</i>-Isopropylsulfinylimines as Useful Intermediates in the Synthesis of Chiral Amines: Expeditive Asymmetric Synthesis of the Calcimimetic (+)-NPS R-568
An efficient and high-yielding approach for the asymmetricsynthesis of calcimimetic (+)-NPS R-568 (1) has been developed. The key step of the synthesis is the highly diastereoselective addition of methyl Grignard to the (SS,E)-N-(3-methoxybenzylidene)-2-propanesulfinamide [5(S)], which afforded a single diastereoisomer in high yield in short reaction time
Reported herein is a straightforward and enantiodivergent synthesis of both enantiomers of trifluoromethylatedanalogues of calcimimeticNPS R-569 in a highly estereoselective manner. The synthesis features a diastereoselective synthesis of the N-(isopropylsulfinyl)imine unit by the "DAG methodology" and a diastereoselective addition of Ruppert-Prakash's reagent to the imine as the key steps. No protecting