Design, synthesis and immunological evaluation of 1,2,3-triazole-tethered carbohydrate-Pam3Cys conjugates as TLR2 agonists.

Novel triazolyl Pam3Cys conjugates encompassing various carbohydrate entities have been synthesized by copper mediated azide-alkyne click chemistry protocol with a view to probe the SAR pertaining to their adjuvant activity in conjunction with OVA as antigen. The preliminary ex vivo cytokine profiling revealed optimal Th1 activation and the in vivo adjuvant studies of ribose derived hybrid (6 e) revealed a marked improvement in the OVA specific antibody IgG response and Th1 cytokine expressions. The triazolyl Pam3Cys carbohydrate conjugates were found to be the hTLR2 agonists as revealed by their SEAP activity due to NFKB activation. The described protocol is the first successful attempt of the amalgamation of carbohydrate-Pam3Cys motifs tethered to a triazole linker as a peptide free adjuvant.

Synthesis and Biological evaluation of novel 4ß-[(5-substituted)-1,2,3,4-tetrazolyl] podophyllotoxins as anticancer compounds.

A series of novel 4ß-[(5-substituted)-1,2,3,4-tetrazolyl] podophyllotoxin derivatives were synthesized by employing azide-nitrile click chemistry approach. All the derivatives were evaluated for their cytotoxicity against a panel of four human cancer cell lines and their IC50 values were found to be in the range of 2.4-29.06 µM. The cytotoxicity exhibited by the majority of test compounds were found to comparable and often more effective than doxorubicin and all compounds exhibited higher cytotoxicity on A-549 cell lines. Cell cycle analysis showed that the novel 4ß-[(5-substituted)-1,2,3,4-tetrazolyl] podophyllotoxins resulted in cell cycle arrest at G2/M phase and were also found to be the potent inhibitors of tubulin polymerization in vitro.

Design and synthesis of novel 1,2,3-triazole derivatives of coronopilin as anti-cancer compounds.

A series of 1,2,3-triazole coronopilin congeners have been designed and synthesized by employing click chemistry approach starting from parthenin and evaluated for their cytotoxicity against a panel of six human cancer cell lines (PC-3, THP-1, HCT-15, HeLa, A-549 and MCF-7). While many compounds exhibited significant anticancer activity, compound 3a, was found to be the most promising analogue in this series with IC50 values of 3.1 µM on PC-3 cell line. Flow-cytometric studies showed that 1,2,3-triazole derivative-3a induce dose dependent apoptosis in the sub G1 phase. This lead molecule-3a was further studied for NF-κB (p65) transcription factor inhibitory activity using Elisa and western blotting analysis which confirmed concentration dependent inhibitory activity against NF-κB, p65 with 80% inhibition in 24 h at 100 µM.