Six aromatic acid esters of heptaacetyl maltosyl were synthesized by reaction of hepta-O-acetyl-α-maltosyl bromide with corresponding aromatic acids, using triethyl benzyl ammonium chloride as a phase -transfer catal...Six aromatic acid esters of heptaacetyl maltosyl were synthesized by reaction of hepta-O-acetyl-α-maltosyl bromide with corresponding aromatic acids, using triethyl benzyl ammonium chloride as a phase -transfer catalyst. In the 1 H NMR spectra of these compounds, the che mical shift of C 1 -H in glycosyl-ring appears at downfield, the coupling constant J 1-2 =8 0~8 3. In the IR spectra of the products, the abso r ption of bending vibration of C 1 -H bond in glycosyl-ring appears at abou t 900 cm -1 . The IR, 1 H NMR spectra confirmed their β-anome r configuration. The greater relative abundances of the molecular ion peak were recorded in the mass spectra of the products. The method has advantages of mild reaction conditions, easy separation and high stereospecifi- city of the pro ducts.展开更多
文摘Six aromatic acid esters of heptaacetyl maltosyl were synthesized by reaction of hepta-O-acetyl-α-maltosyl bromide with corresponding aromatic acids, using triethyl benzyl ammonium chloride as a phase -transfer catalyst. In the 1 H NMR spectra of these compounds, the che mical shift of C 1 -H in glycosyl-ring appears at downfield, the coupling constant J 1-2 =8 0~8 3. In the IR spectra of the products, the abso r ption of bending vibration of C 1 -H bond in glycosyl-ring appears at abou t 900 cm -1 . The IR, 1 H NMR spectra confirmed their β-anome r configuration. The greater relative abundances of the molecular ion peak were recorded in the mass spectra of the products. The method has advantages of mild reaction conditions, easy separation and high stereospecifi- city of the pro ducts.