Stereoselective Synthesis of Protected (2R,3R,4S)-4,7-Diamino-2,3-dihydroxyheptanoic Acid: A Novel Amino Acid of Callipeltins A and D
摘要:
An orthogonally protected derivative 1 of (2R,3R,4S)-4,7diamino-2,3-dihydroxyheptanoic acid, the unusual amino acid residue of the biologically active marine peptides such as callipeltins A and D and neamphamide A, was efficiently prepared in 10 steps and 30% overall yield from a commercially available L-ornithine derivative 2. The key step includes the N-diphenyl methylene-control led diastereoselective dihydroxylation of (Z)-ester 3 with > 13:1 selectivity for the desired isomer.