PARADIGM AND ADVANTAGE OF CARBOHYDRATE CLICK CHEMISTRY STRATEGY FOR FUTURE DECOUPLING - Click Chemistry in Glycoscience: New Developments and Strategies - page 10

CO 2 H CO 2 H

H 2 N H 2 N

cysteine
alkylation

Peptide Peptide

H

OR

SH S

O

RO

N 3

Cu(I)

O

H 2 N CO 2 H

Peptide

OR

S

O

RO

N

O

N

N

FIGURE 1.4 Chapleur et al.'s synthetic strategy for neoglycopeptides construction.

Fiore, Marra, and Dondoni [21] took advantage of photoinduced coupling of
anomeric sugar thiols with sugar alkenes to synthesize 1,6-linked S -disaccharides
in good to excellent yields (76-92%) and high diastereoselectivities (up to 99%).
Figure 1.5 shows a typical example of the synthesized disaccharide.
Stenzel and coworkers [22] synthesized a block copolymer containing
di(ethylene glycol) methyl ether methacrylate (DEGMA) and 2-hydroxyethyl
methacrylate (HEMA) by reversible addition-fragmentation chain transfer (RAFT)
polymerization, which was subsequently modified with glucothiose. Glucothiose
was introduced via UV-promoted TEC process. The resulting glycosylated block
copolymer led to the formation of thermoresponsive micelles, a potential candidate
for targeted drug delivery. Figure 1.6 illustrates the methodology.

OMe

OAc

O

O

O

Ac AcO

+

SH

OMe OMe
h

OAc

O O

ν (365 nm)

CH 2 Cl 2

OAc

O

Ac AcO

S

OMe

OAc O

Isolated yield = 92%
dr > 99:1

O O

FIGURE 1.5 Example of Dondoni et al.'s [21] photoinduced TEC as a click ligation tool for
thiodisaccharide synthesis.