Chemical Synthesis of Two Fucosylated Human Milk Oligosaccharides: 3‐Fucosyllactose and Lacto‐<i>N</i>‐fucopentaose V

Glycans present in human milk have been the focus of many studies due to challenges associated with their synthesis. The development of new methods for obtaining individual glycans found in human milk has been a vibrant area of research in glycosciences. This study reports the synthesis of two fucosylated glycans found in human milk, 3-fucosyllactose, which was previously synthesized by both chemical and enzymatic methods, and the first chemical synthesis of lacto-N-fucopentaose V. Screening different protecting and leaving groups, as well as optimizing the glycosylation reaction conditions helped us to achieve efficient assembly and deprotection of these two fucosylated human milk oligosaccharides in good yields.