摘要:
Synthesized from D-xylose, methyl 5-deoxy-alpha-D-xylofuranoside (1) and methyl 5-deoxy-beta-D-xylofuranoside (2) were obtained in overall yields of 24 and 26 %, respectively. The key step in the synthesis was the separation of an anomeric mixture on a strong anion exchanger in OH- form. NMR data and mass spectra of title compounds 1, 2, methyl 2,3-di-O-acetyl-5-deoxy-alpha-D-xylofuranoside (3), and methyl 2,3-di-O-acetyl-5-deoxy-beta-D-xylofuranoside (4) are discussed. The conformations of 1 and 2 were established from the best fit between calculated and experimental coupling constants using Karplus equation.