131613-94-0Relevant articles and documents
Total Synthesis of 6-Deoxy-6-aminoheptopyranuronic Acid Derivatives
Casiraghi, Giovanni,Colombo, Lino,Rassu, Gloria,Spanu, Pietro
, p. 6523 - 6527 (2007/10/02)
Two enantio couples of terminal C-glycoyranosyl α-amino acids, namely the aminopyranuronic acid, L-9, D-9 and L-10, D-10, hve been synthesized from serine-derived pair L-2, D-2 by exploiting enantiomerically pure butenolide intermediates 3 and 4.The key synthetic steps involved the sequential antiselective cis dihydroxylation of the butenolide double bond and the clean furaose-to-pyranose ring expansion to construct the sugar skeleton with the proper stereochemistry.In our best performance, homogeneous L-9 was prepared from L-2 in four steps and 10 reactions in 20percent overall yield.
THE FOUR-CARBON ELONGATION OF THREE-CARBON CHIRAL SYNTHONS USING 2-(TRIMETHYLSILOXY)FURAN: HIGHLY STEREOCONTROLLED ENTRY TO ENANTIOMERICALLY PURE SEVEN-CARBON α,β-UNSATURATED 2,3-DIDEOXYALDONOLACTONES
Casiraghi, Giovanni,Colombo, Lino,Rassu, Gloria,Spanu, Pietro,Fava, Giovanna Gasparri,Belicchi, Maria Ferrari
, p. 5807 - 5824 (2007/10/02)
The BF3-promoted addition of 2-(trimethylsiloxy)furan to three carbon synthons derived from D- and L-glyceraldehyde, D- and L-serinal, and imines thereof furnishes C7 α,β-unsaturated 2,3-dideoxy-aldonolactone derivatives in high yield, with very high level of diastereoselection.In all the cases, compounds having 4,5-threo:5,6-erythro relative stereodisposition preferentially emerge from the reactions, accompanied by only marginal amounts of 4,5-erythro:5,6-threo epimers.An empirical rule for the rapid assignment of the configuration at C-4 (γ-carbon) of γ-substituted unsaturated and saturated β-butyrolactones is given, based upon the sign of the optical rotation values.
