Synthesis of triazolylmethyl-linked nucleoside analogs via combination of azidofuranoses with propargylated nucleobases and study on their cytotoxicity

Construction of 5-Fluorouracil and Gallium Corrole Conjugates for Enhanced Photodynamic Therapy

Molecular hybridization is a well-established strategy for developing new drugs. In the pursuit of promising photosensitizers (PSs) with enhanced photodynamic therapy (PDT) efficiency, a series of novel 5-fluorouracil (5FU) gallium corrole conjugates (1-Ga-4-Ga) were designed and synthesized by hybridizing a chemotherapeutic drug and PSs. Their photodynamic antitumor activity was also evaluated. The most active complex (2-Ga) possesses a low IC50 value of 0.185 μM and a phototoxic index of 541 against HepG2 cells. Additionally, the 5FU-gallium corrole conjugate (2-Ga) exhibited a synergistic increase in cytotoxicity under irradiation. Excitedly, treatment of HepG2 tumor-bearing mice with 2-Ga under irradiation could completely ablate tumors without harming normal tissues. 2-Ga-mediated PDT could disrupt mitochondrial function, cause cell cycle arrest in the sub-G1 phase, and activate the cell apoptosis pathway by upregulating the cleaved PARP expression and the Bax/Bcl-2 ratios. This work provides a useful strategy for the design of new corrole-based chemo-photodynamic therapy drugs.

Synthesis of new 1,2,3-triazolo-nucleoside analogues with 2-propargylamino pyrimidines via click reactions

In this study, it was reported that twelve nucleoside analogues were synthesized by click reactions. The reactions were carried out between the azide derivatives of D-glucopyranose, D-galactopyranose, D-ribofuranose and 2-propargylamino pyrimidine derivatives (5 and 7) that are synthesized via a different route for the first time. In the first step, N-propargyl guanidine was obtained with the reaction of 1H-pyrazole-1-carboxamidine hydrochloride and propargyl amine, then condensation of N-propargyl guanidine and β-diketone (4 and 6) resulted in 2-propargylamino pyrimidines (5 and 7) for the first time in good yields (85%). Finally, click reactions were performed with azidosugars (8a-8f) and 2-propargylamino pyrimidine derivatives and produced twelve new nucleoside analogues in good yields. (9a-9f, 10a-10f, 65-73% yields). The chemical structures of the new derivatives were elucidated spectroscopic techniques, such as FT-IR, ¹H NMR, ¹⁹F NMR, ¹³C NMR and TOF-ESI-MS.

Cu(I)-Catalyzed Click Chemistry in Glycoscience and Their Diverse Applications

Copper(I)-catalyzed 1,3-dipolar cycloaddition between organic azides and terminal alkynes, commonly known as CuAAC or click chemistry, has been identified as one of the most successful, versatile, reliable, and modular strategies for the rapid and regioselective construction of 1,4-disubstituted 1,2,3-triazoles as diversely functionalized molecules. Carbohydrates, an integral part of living cells, have several fascinating features, including their structural diversity, biocompatibility, bioavailability, hydrophilicity, and superior ADME properties with minimal toxicity, which support increased demand to explore them as versatile scaffolds for easy access to diverse glycohybrids and well-defined glycoconjugates for complete chemical, biochemical, and pharmacological investigations. This review highlights the successful development of CuAAC or click chemistry in emerging areas of glycoscience, including the synthesis of triazole appended carbohydrate-containing molecular architectures (mainly glycohybrids, glycoconjugates, glycopolymers, glycopeptides, glycoproteins, glycolipids, glycoclusters, and glycodendrimers through regioselective triazole forming modular and bio-orthogonal coupling protocols). It discusses the widespread applications of these glycoproducts as enzyme inhibitors in drug discovery and development, sensing, gelation, chelation, glycosylation, and catalysis. This review also covers the impact of click chemistry and provides future perspectives on its role in various emerging disciplines of science and technology.

1,2,3-Triazole-containing hybrids as potential anticancer agents: Current developments, action mechanisms and structure-activity relationships

Anticancer agents are critical for the cancer treatment, but side effects and the drug resistance associated with the currently used anticancer agents create an urgent need to explore novel drugs with low side effects and high efficacy. 1,2,3-Triazole is privileged building block in the discovery of new anticancer agents, and some of its derivatives have already been applied in clinics or under clinical trials for fighting against cancers. Hybrid molecules occupy an important position in cancer control, and hybridization of 1,2,3-triazole framework with other anticancer pharmacophores may provide valuable therapeutic intervention for the treatment of cancer, especially drug-resistant cancer. This review emphasizes the recent advances in 1,2,3-triazole-containing hybrids with anticancer potential, covering articles published between 2015 and 2019, and the structure-activity relationships, together with mechanisms of action are also discussed.