Variable strategy toward carbasugars and relatives. 6. Diastereoselective synthesis of 2-deoxy-2-amino-5a-carba-beta-L-mannopyranuronic acid and 2-deoxy-2-amino-5a-carba-beta-L-mannopyranose.
Efficient, total syntheses of novel 2-deoxy-2-amino-5a-carba-beta-L-mannopyranuronic acid (1) and 2-deoxy-2-amino-5a-carba-beta-L-mannopyranose (2), a positional stereoisomer of validamine, have been achieved in 28% and 24% overall yields and in 12 steps and 13 steps, respectively, from 2-[(tert-butyldimethylsilyl)oxy]furan (3) and (2S)-2,3-O-isopropylideneglyceraldehyde N-benzyl imine (4) via two highly diastereoselective Mukaiyama aldol-related chemical maneuvers. The strategy, which furnishes the targeted carbasugars in enantiopure forms, allows for complete control of the configuration at all five contiguous stereocenters of the targets by utilizing the sole element of chirality present in the aldimine progenitor 4.
Rassu
Gloria
G
Istituto di Chimica Biomolecolare del CNR, Sezione di Sassari, Traversa La Crucca 3, I-07040 Li Punti, Sassari, Italy. giovanni.casiraghi@unipr.it
Auzzas
Luciana
L
Zambrano
Vincenzo
V
Burreddu
Paola
P
Pinna
Luigi
L
Battistini
Lucia
L
Zanardi
Franca
F
Casiraghi
Giovanni
G
D007294:Inositol / Q000031:analogs & derivatives* / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009005:Monosaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D014574:Uronic Acids / Q000138:chemical synthesis* / Q000737:chemistry
C484619:2-deoxy-2-amino-5a-carba-beta-L-mannopyranose; C484618:2-deoxy-2-amino-5a-carba-beta-L-mannopyranuronic acid; D009005:Monosaccharides; D014574:Uronic Acids; C042908:validamine; D007294:Inositol