作者:Yu Cai、Zhiwei Ma、Jintao Jiang、Concordia C. L. Lo、Shi Luo、Ankur Jalan、Joseph M. Cardon、Alexander Ramos、Diego A. Moyá、Daniel Joaquin、Steven L. Castle
DOI:10.1002/anie.202014238
日期:2021.3
β‐tert‐hydroxy amino acids were prepared by regioselective aminohydroxylation involving a chiral mesyloxycarbamate reagent. Stereospecific construction of the E‐ and Z‐ΔIle residues was accomplished through a one‐pot reaction featuring anti dehydration, azide reduction, and O→N acyl transfer. Alkene isomerization was negligible during this process. These methods enabled a highly convergent and efficient synthetic
Asymmetric Synthesis of Four Diastereomers of 3-Hydroxy-2,4,6-trimethylheptanoic Acid: Proof of Configurational Assignment
作者:Jeffrey A. Turk、Gonzalo S. Visbal、Mark A. Lipton
DOI:10.1021/jo034738l
日期:2003.10.1
Four unique diastereomers of 3-hydroxy-2,4,6-trimethylheptanoic acid-(2R,3R,4R), (2S,3R,4R), (2S,3R,4S), and (2R,3R,4S)-the fatty acid component of callipeltin A and D, have been synthesized from commercially available (+)- and (-)-pseudoephedrine propionamide in 6 steps and 59% average overall yield. Comparison of the H-1 and C-13 NMR and optical rotation data of the resulting isomers with the natural fragment unambiguously verifies the configurational assignment of the natural isomer as (2R,3R,4R).