Triazolyl glycoconjugates

Scheme 6.3 Click-inspired synthesis of morpholine-fused triazolyl glycoconjugates.

Similar click protocol was employed for synthesis of ferrocene-based triazolyl glycoconjugates 23 by reacting ferrocenyl azide 22 and terminal sugar-based acetylenic compound 21 under click condition. Resultant ferrocenyl glycoconjugate 23 is supposed to be applicable for the study of protein-carbohydrate interaction using electrochemical biosensing techniques (Scheme 6.7) [23]. 

Scheme 6.7 Synthesis of ferrocene-containing triazolyl glycoconjugates.

The triazolyl glycoconjugates displayed an impressive effect for inhibiting PTPs enzymes and are considered as potential therapeutic agents. A AfW"-accelerated CuAAC of sugar alkyne 53 with azide 54 followed by demethylation afforded triazolyl glycoconjugate 56 (Scheme 6.15). The molecule 56 (IC50 = 5.1 pM) was identified as a selective and potent inhibitor of PTPIB [33]. 

Scheme 6.15 Triazolyl glycoconjugates as selective PTP1B inhibitors.

D-Mannose-based alkyne, on similar clicking with 0-, m-, and / -substituted azido benzoic acid esters, afforded triazolyl glycoconjugates 65-67 (Scheme 6.17). These molecules were evaluated for their in vitro cytotoxic activity against seven cancer cell lines, where compound 65 showed increased activity (IC50 = 23.8 pM) than precursor 63 (ICgg = 93.2 pM) for CEM lymphoblasts. Also, deacetylation of compound 65 results in dramatic loss of activity [39]. 

Figure 6.2 Diverse triazolyl glycoconjugates as glycogen phosphorylase inhibitors.

Scheme 6.16 Synthesis of triazolyl glycoconjugate as antiproliferative activity.

Figure 6.6 Triazolyl glycoconjugates as antifungal and antibacterial agents.

Scheme 6.23 Synthesis of a-tocopherol-based triazolyl glycoconjugate.

Scheme 6.24 Click-inspired synthesis of rapamycin triazolyl glycoconjugate.

Scheme 6.30 Synthesis of triazolyl glycoconjugate 119 as suitable ligand.

A fluorescent glycosyl azide 127 was clicked with alkyne 128 and afforded fluorescent triazolyl glycoconjugate 129 (Scheme 6.34). The developed fluorescent-labeled biomolecules 129 are likely to be an important tool for investigating various biological events. The fluorescent glycosyl conjugates were used to trace the translocation route of glycosyl pesticides within plants [75]. 

Iglesias-Guerra and coworkers, prepared aziridine galactopyranoside derivatives and studied their anticancer activity. Guo et al. presented efficient one-pot synthesis of tigogenin saponin. Tiwari et al used click chemistry to synthesize triazolyl ethisterone glycoconjugates. D Andrea et al. presented stereoselective synthesis of p-D-GlcNAc-(l 4)-D-Glc disaccharide starting from lactose. Martin and coworkers, presented synthesis of L-sorbose derivatives. Authors made a critical review of the spectral data available in literature. 

Three different series of diverse triazolyl 0-benzylquercetin glycoconjugates were synthesized using CuAAC for investigating them against leishmaniasis. After incorporation of propargyl group at three different positions (C-3 or C-5 or both C-3 and C-5) of benzylated quercetin, resultant 0-benzylquercetin alkynes... 

Scheme 6.9 Synthesis of antileishmanial triazolyl 0-benzylquercetin glycoconjugates.

Interestingly, the triazolyl azobenzene glycoconjugate could be switched between two geometrical isomeric states to change the spatial orientation of the... 

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