Scheme 1. Synthetic scheme of A-MNGs using diethylmalonate as a starting material. Two different alkyl groups (R₁CH₂- and R₂CH₂-) were sequentially introduced into diethylmalonate to stepwise give mono-alkylated malonates (A) and di-alkylated propane-1,3-diol (B) in high yields (∼90% for each step). Two maltose units were attached to the resulting di-alkylated diol derivatives (B) via β-selective glycosylation and global deprotection with a high yield.