Totally stereoselective synthesis of 1,3-disaccharides through Diels-Alder reactions.
A nonclassical, totally stereoselective synthesis of orthogonally protected 1,3-disaccharides is reported. Enantiomerically pure beta-keto-delta-lactones, efficiently obtained from glucal and galactal, are transformed into electron-poor heterodienes and chemo-, regio-, and stereoselectively cycloadded to glycals as electron-rich dienophiles, to directly afford 2-thiodisaccharides. The reductive desulfurization of the latter smoothly gave the corresponding 2,2'-dideoxydisaccharides.
Dipartimento di Chimica Organica Ugo Schiff, Universita' di Firenze, and CNR-ICCOM, via della Lastruccia, 13 I-50019 Sesto Fiorentino (FI), Italy.
Alessandra
A
Bartolozzi
Stefania
S
Pacciani
Cecilia
C
Benvenuti
Martina
M
Cacciarini
Francesca
F
Liguori
Stefano
S
Menichetti
Cristina
C
Nativi
D002125:Calcium Gluconate / Q000737:chemistry; D002240:Carbohydrate Sequence; D014128:Chromomycin A3 / Q000737:chemistry; D003500:Cyclization; D004187:Disaccharides / Q000138:chemical synthesis*; D005690:Galactose / Q000031:analogs & derivatives* / Q000737:chemistry; D007659:Ketones / Q000737:chemistry; D007783:Lactones / Q000737:chemistry; D008969:Molecular Sequence Data; D011714:Pyrans / Q000737:chemistry; D011809:Quinones / Q000737:chemistry; D013237:Stereoisomerism; D013438:Sulfhydryl Compounds / Q000737:chemistry
D004187:Disaccharides; D007659:Ketones; D007783:Lactones; D011714:Pyrans; D011809:Quinones; D013438:Sulfhydryl Compounds; C002038:galactal; D014128:Chromomycin A3; D002125:Calcium Gluconate; D005690:Galactose