AUTHOR=Li Huiting , Mao Hongzhao , Chen Chao , Xu Ying , Meng Shuai , Sun Tiantian , Zong Chengli 

TITLE=Efficient synthesis of α-galactosylceramide and its C-6 modified analogs

JOURNAL=Frontiers in Chemistry

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2022.1039731

DOI=10.3389/fchem.2022.1039731

ISSN=2296-2646

ABSTRACT=<p>The synthesis of α-galactosylceramide (KRN7000) and its C-6 modified analogs remains a challenge due to the difficult α-1,2-<italic>cis</italic>-glycosidic bond. A non-participating benzyl (Bn) protecting group has been commonly used to favor the α-glycosylation product. Here, we report the α-selective glycosylation by using a bulky 4,6-O-di-<italic>tert</italic>-butylsilylene (DTBS) galactosyl donor, regardless of the 2-benzoyl (Bz) participating group. Compared with Bn, Bz groups can be selectively removed in basic conditions without impacting the C-6 azide modification. The azide has the potential for clicking with alkyne or being easily transformed to other functional groups.</p>