The synthesis of L (-) and D (+) lupinic acid

Update 1 of: α,β-Diamino Acids: Biological Significance and Synthetic Approaches

“…A different approach takes advantage of the Michael-acceptor character of α,β-unsaturated acid derivatives to nitrogen nucleophiles. Within this context, α,β-dehydroalanine derivatives have been extremely useful starting materials containing the α-nitrogen for the Michael addition of amines. , In an interesting example of the above methodology (Scheme ) from the group of Belokon, the asymmetric synthesis of α,β-diamino acids is performed via a chiral complex of Ni(II) with a dehydroalanine derivative, 357 . The presence of chiral ligand 359 in the complex provides a high facial discrimination for the attack of an amine, affording the Re adduct 358 in diastereomeric ratios ranging from 90:10 to 97:3 depending on the nature of the reacting amine.…”

Hydrolysis of Amides

“…At DSM, already over 100 different a-H-a-amino acid amides have been successfully resolved, furnishing both the L-amino acid and D-amino acid amide in high enantiomeric excess. The size of the side chain may range from the small methyl group in alanine amide to the very bulky group in b-naphthylglycine amide or lupinic acid amide [166,168,216]. Furthermore, heteroatoms like sulfur, nitrogen, and oxygen are accepted in alkyl or (hetero)aryl side chains.…”

Use of Enzymes in the Synthesis of Amino Acids

“…So far over 100 different a-H-a-amino acid amides have been successfully resolved. The size of the side-chain may range from the small methyl group in alanine to the very bulky group of lupinic acid [46]. Furthermore, the alkyl or aryl side-chains may contain heteroatoms like sulfur, nitrogen, and oxygen.…”