Regio- and stereocontrolled selective debenzylation and substitution reactions of C-2 formyl glycals. Application in the synthesis of constrained beta-sugar amino acids.
O-Benzyl-protected C-2 formyl glycals are regioselectively deprotected and acetylated first at C-3 and then at C-6 upon treatment with a ZnCl2-Ac2O-AcOH reagent combination. Treatment of the thus-obtained C-3 acetate with various nucleophiles leads to substitution at C-3 with retention of stereochemistry in the galactal series, whereas mixed results were obtained with glucal-derived compounds. Two of the azido-substituted products were converted into the corresponding beta-sugar amino acids.
Rawal
Girish K
GK
Department of Chemistry, Indian Institute of Technology, Kanpur 208016, India.
Rani
Shikha
S
Kumari
Nitee
N
Vankar
Yashwant D
YD
D000596:Amino Acids / Q000138:chemical synthesis* / Q000737:chemistry; D002241:Carbohydrates / Q000138:chemical synthesis* / Q000737:chemistry; D006027:Glycosides / Q000737:chemistry*; D008968:Molecular Conformation; D013237:Stereoisomerism
D000596:Amino Acids; D002241:Carbohydrates; D006027:Glycosides