Seven new aminoacyl sugars in Ipomoea batatas

An analysis of the polar extracts from sweet potato Ipomoea batatas (Convolvulaceae) led to the isolation of seven unknown aminoacyl sugars. On the basis of 1 D, 2D NMR, and mass spectrometry data, the structures of the compounds were elucidated as: β-D-fructofuranosyl-(2 → 1)-α-D-[2-O-valyl]-glucopyranoside (1), β-D-fructofuranosyl-(2 - 1)-a-D-[2-O-tyrosyl]-glucopyranoside (2), β-D-fructofuranosyl-(2 → 1)-α-D-[2-O-threonyl]-glucopyranoside (3), β-D-fructofuranosyl-(2 → 1)-α-D-[2-O-hystidyl]-glucopyranoside (4), 2-β-D-fructofuranosyl-(2 - 1)-a-D-[2-O-alanyl]-glucopyranoside (5), β-D-fructofuranosyl-(2 → 1)-α-D-[2-O-tryptophanyl]-glucopyranoside (6), and β-D-fructofuranosyl-(2 → 1)-α-D-[2-O-glycyl]-glucopyranoside (7).