C-Glycosides Synthesis

The majority of techniques benefit from the creation of the glycosidic C—C bond. The glycosyl donor precursors, which are often utilised in the synthesis of O-glycosides and are simple for non-specialists to obtain, are used here to group these C-glycosylation techniques. They consist of glycosyl halides, glycals, sugar acetates, lactols, lactones, 1,2-anhydro sugars, selenoglycosides/telluroglycosides, methyl glycosides, and glycosyl imidates/phosphates. Each form of sugar precursor is treated as a subcategory under the C-glycosylation processes, which can be mediated by glycosyl electrophilic/cationic species, anionic species, radical species, or transition-metal complexes. The Claisen, Ramberg-Backlund, and 1,2-Wittig rearrangements are only a few examples of intramolecular rearrangements, which often include coordinated processes and fall under the category of C-glycosylations. The development of pyranoside/furanoside rings following the creation of the C-glycosylations provides an alternative to the C-glycosylations.