Amino acids, XV: Synthesis of enantiopure DAVA-derivatives (5-amino-4-hydroxypentanoic acids) from (S)-glutamic acid

Article abstract of DOI:10.1002/ardp.19943270108

Starting from (S)-glutamic acid the readily available hydroxymethyl lactone 1 is protected as the TBDPS ether 2. Alkylation of the lithium enolate of 2 provides the lactones 3a,b with high diastereomeric excess. On the other hand 1,4 addition of Gilman cuprates to 10 furnishes the alcohols 12a,b after deprotection. Transformation of 4,12 via the mesylates 5,13 and the azides 6,14 affords the Boc protected amines 7,15 after catalytic hydrogenation in the presence of Boc₂O. After treatment of 7,15 with methanolic HCl the rings of the crystalline hydrochlorides 8,16 are opened to the DAVA-derivatives (δ-aminovaleric acid derivatives) 9,17.