Hunt Kaarel Erik, Miller Annette, Liias Kristin, Jarg Tatsiana, Kriis Kadri, Kanger Tõnis
Department of Chemistry and Biotechnology, Tallinn University of Technology, Akadeemia tee 15, 12618 Tallinn, Estonia.
J Org Chem. 2025 Jan 10;90(1):663-671. doi: 10.1021/acs.joc.4c02582. Epub 2024 Dec 29.
Configurational differences in monosaccharides determine the products and selectivity of the transesterification reaction with lipase-B (CAL-B). The β-anomers of peresterified pyranose monosaccharides tend to yield anomeric deprotection products, while the α-anomers preferentially react at the sixth or fourth position. CAL-B differentiates between enantiomers, either reacting more rapidly with d-enantiomers of monosaccharides or having a different selectivity based on the enantiomer. Pivaloylated and benzoylated saccharides are the limits of the CAL-B transesterification reaction, while lower boiling point alcohols such as MeOH and EtOH can replace -BuOH as the nucleophilic reagent. Finally, CAL-B can be successfully recycled in both long and short reaction time reactions.
单糖的构型差异决定了与脂肪酶B(CAL-B)进行酯交换反应的产物和选择性。全酯化吡喃糖单糖的β-异头物倾向于生成异头物脱保护产物,而α-异头物则优先在第六或第四位发生反应。CAL-B能够区分对映体,要么与单糖的d-对映体反应更快,要么基于对映体具有不同的选择性。新戊酰化和苯甲酰化的糖类是CAL-B酯交换反应的极限,而沸点较低的醇类,如甲醇和乙醇,可以替代叔丁醇作为亲核试剂。最后,CAL-B在长反应时间和短反应时间的反应中都能成功循环使用。