New stereodivergent approach to 3-amino-2,3,6-trideoxysugars. Enantioselective synthesis of daunosamine, ristosamine, acosamine, and epi-daunosamine.
[reaction: see text] An enantioselective preparation of the four diastereomeric 3-amino-2,3,6-trideoxy-hexoses, key components of anthracycline antibiotics, has been developed. Sharpless catalytic asymmetric epoxidation of the (2E)-2,5-hexadien-1-ol, regioselective ring opening with azide, followed by convenient functional group transformations, afforded the key aldehydes cis- or trans-6 in any configuration. The diastereoselective addition of methylmetal reagents to these aldehydes followed by ozonolysis gives access in a completely stereocontrolled manner to the four isomeric trideoxyaminosugars.
Ginesta
Xavier
X
Unitat de Recerca en Síntesi Asimètrica (URSA-PCB), Departament de Química Orgànica/Parc Científic de Barcelona, Universitat de Barcelona, C/Josep Samitier 1-5, 08028 Barcelona, Spain.
Pastó
Mireia
M
Pericàs
Miquel A
MA
Riera
Antoni
A
D000447:Aldehydes / Q000737:chemistry; D001386:Azides / Q000737:chemistry; D002236:Carbohydrate Conformation; D006595:Hexosamines / Q000138:chemical synthesis* / Q000737:chemistry; D008745:Methylation; D010126:Ozone / Q000737:chemistry; D013237:Stereoisomerism
D000447:Aldehydes; D001386:Azides; D006595:Hexosamines; C007217:daunosamine; C010783:ristosamine; C010669:acosamine; D010126:Ozone