Glycosyl donors have been experimentally shown to have a high tendency for acyl transfer to the alcohol nucleophile as a major side product during glycosylation reactions. Therefore, a neighbouring group participatory mechanism of glycosylation is explored using D-galactopyranose based donor having 2-O-acyl functionality by employing density functional theory. The reaction proceeds via galactopyranosyl dioxolenium ion as a stable intermediate, which leads to the formation of α-glycoside 4, orthoester (5 or 6) and acyl transfer 7 as side products. The mechanism of the stereoselective formation of β-glycoside is investigated. Moreover, all the possible intermediates and transition states have been explored.

实验表明，糖基供体在糖基化反应过程中具有作为主要副产物的酰基转移至醇亲核体的高度趋势。因此，通过使用密度泛函理论，使用具有2-O-酰基官能团的基于D-吡喃半乳糖的供体来探索糖基化的邻近基团参与机制。该反应通过作为稳定中间体的吡喃半乳糖基二恶唑鎓离子进行，这导致形成α-糖苷4，原酸酯（5或6）和酰基转移7作为副产物。研究了β-糖苷立体选择性形成的机理。而且，已经研究了所有可能的中间体和过渡态。