New 1,2,3-triazole linked flavonoid conjugates: Microwave-assisted synthesis, cytotoxic activity and molecular docking studies

Diastereoselective Anomeric C(sp3)-H Cyclization Towards the Design of New Cyclophane-Braced Glycopeptides

Here we report a macrocyclization route towards the synthesis of glycophane peptides by a selective C-H arylation of the anomeric bond. This approach demonstrates the power of Pd-catalysis C-H activation to access unusual cyclic peptides.

Recent advances in microwave-assisted synthesis of triazoles and their derivatives: a green approach toward sustainable development methods

Triazole, a nitrogen-containing five-membered heterocycle with two isomeric forms, 1,2,3-triazole and 1,2,4-triazole, has proven to be a valuable component in the pharmaceutical domain. Owing to its widespread utility in drug development, pharmaceutical and medicinal chemistry, several synthetic methods have been explored, such as different catalytic systems, solvents, and heating methodologies in recent years. However, some methods were associated with several limitations, such as harsh reaction conditions, high temperatures, low atom economy, and long reaction times. Conversely, the ongoing demand from the chemical industry has led to increased attention on overcoming these limitations and developing sustainable laboratory methods. In recent years, the microwave heating method in organic synthesis has evolved as a new, environmentally friendly approach with benefits such as atom economy, reduced use of hazardous chemicals, safer chemical design, few derivatives and enhanced energy efficiency. This review summarizes recent progress in microwave-assisted synthesis of triazoles (1,2,3-triazole and 1,2,4-triazole), with a comparative analysis between conventional methods and microwave-assisted methods in terms of reaction time, yield, green synthesis, sustainability and other relevant factors.

Facile Synthesis and Applications of Flavonoid-Heterocyclic Derivatives

Flavonoids belong to the polyphenol group that naturally exists in fruits, vegetables, tea, and grains. Flavonoids, as secondary metabolites, show indispensable contributions to biological processes and the responses of plants to numerous environmental factors. The bioactivity of flavonoids depends on C6-C3-C6 ring substitution patterns that exhibit bioactive antioxidant, antimicrobial, antifungal, antitumor, and anti-inflammatory properties. The synthesis of flavonoids has been reported by various methodologies. Therefore, the present review systematically summarizes the synthesis of recent heterocyclic flavonoid derivatives via facile synthetic approaches since the research in flavonoids is useful for therapeutic and biotechnology fields.

Novel flavonoid derivatives containing 1,2,4-triazole Schiff bases as potential antifungal agents: design, synthesis, and biological evaluation

A series of flavonol derivatives containing 1,2,4-triazole Schiff base was designed, synthesized and tested for their biological activities. The results of the biological activity test showed that compounds exhibited the obvious antifungal activities against Sclerotinia sclerotiorum (S.s), Rhizoctonia solani (R.s), Botrytis cinerea (B.c) and Phomopsis sp (P.s). Among them, K14 showed excellent antimicrobial activity against B.c with the half maximal effective concentration (EC50) of 7.6 µg/mL as compared to azoxystrobin (18.0 µg/mL). Additionally, the in vivo protective and therapeutic activities of K14 on blueberry leaves were 94.1 and 88.7 % respectively, surpassing than that of the control drug azoxystrobin (91.6 and 74.4 %) at 200 µg/mL. The results of SEM showed that the mycelium appeared wrinkled, folded and changed in morphology after being treated with K14. In addition, fluorescence microscopy (FM) and cytoplasmic leakage assays showed that the cell membrane of B.c was disrupted. Further study of malondialdehyde (MDA) and relative conductivity measurements indicated that the normal function of cells is affected by K14 by increasing cell membrane permeability and promoting membrane lipid peroxidation. These results indicate that flavonol derivatives containing 1,2,4-triazole Schiff bases are expected to provide a new prospect for the development of novel fungicides.

Structural investigation of interactions between halogenated flavonoids and the lipid membrane along with their role as cytotoxic agents

This study focuses on understanding the structural and molecular changes in lipid membranes under the influence of six halogenated flavonoid derivatives differing in the number and position of substitution of chlorine and bromine atoms (D1-D6). Utilizing various analytical techniques, including fluorometric methods, dynamic light scattering (DLS), attenuated Fourier transform infrared spectroscopy (ATR- FTIR), and FT-Raman spectroscopy, the research aims to elucidate the mechanisms underlying the interaction of flavonoids with cell membranes. Additionally, the study includes in silico analyses to explore the physicochemical properties of these compounds and their potential pharmaceutical applications, along with toxicity studies to assess their effects on cancer, normal, and red blood cells. Our study showed the ability of halogenated derivatives to interact mostly with the outer part of the membrane, especially in the lipid heads region however, some of them were able to penetrate deeper into the membrane and affect the fluidity of hydrocarbon chains. The potential to reduce cancer cell viability, the lack of toxicity towards erythrocytes, and the favourable physicochemical and pharmacokinetic properties suggest these halogenated flavonoids potential candidates for exploring their potential for medical use.

The anti-breast cancer therapeutic potential of 1,2,3-triazole-containing hybrids

Breast cancer, as one of the most common invasive malignancies and the leading cause of cancer-related deaths in women globally, poses a significant challenge in the world health system. Substantial advances in diagnosis and treatment have significantly improved the survival rate of breast cancer patients, but the number of incidences and deaths of breast cancer are projected to increase by 40% and 50%, respectively, by 2040. Chemotherapy is one of the principal treatments for breast cancer therapy, but multidrug resistance and severe side effects remain the major obstacles to the success of treatment. Hence, there is a vital need to develop novel chemotherapeutic agents to combat this deadly disease. 1,2,3-Triazole, which can be effectively constructed by click chemistry, not only can serve as a linker to connect different anti-breast cancer pharmacophores but also is a valuable pharmacophore with anti-breast cancer potential and favorable properties such as hydrogen bonding, moderate dipole moment, and enhanced water solubility. Particularly, 1,2,3-triazole-containing hybrids have demonstrated promising in vitro and in vivo anti-breast cancer potential against both drug-sensitive and drug-resistant forms and possessed excellent selectivity by targeting different biological pathways associated with breast cancer, representing privileged scaffolds for the discovery of novel anti-breast cancer candidates. This review concentrates on the latest advancements of 1,2,3-triazole-containing hybrids with anti-breast cancer potential, including work published between 2020 and the present. The structure-activity relationships (SARs) and mechanisms of action are also reviewed to shed light on the development of more effective and multitargeted candidates.

Site-Selective Palladium(II)-Catalyzed Methylene C(sp3)-H Diarylation of a Tropane Scaffold

A series of 2,4-di-arylated tropane derivatives was synthesized through a site-selective palladium-catalyzed β-C(sp³)-H di-arylation process. This type of structure has been scarcely reported in literature. They nevertheless represent an interesting class of biologically relevant molecules as illustrated by the observed activity at the micromolecular level of eight derivatives toward human colorectal cancer cell line HCT116.

Recent Advances in Bioactive Flavonoid Hybrids Linked by 1,2,3-Triazole Ring Obtained by Click Chemistry

As a result of the biological activities of natural flavonoids, several synthetic strategies aiming to obtain analogues with improved potency and/or pharmacokinetic profile have been developed. Since the triazole ring has been associated with several biological activities and metabolic stability, hybridization with a 1,2,3-triazole ring has been increasingly reported over the last years. The feasible synthesis through copper (I) catalyzed azide-alkyne cycloaddition (CuAAC) has allowed the accomplishment of several hybrids. Since 2017, almost 700 flavonoid hybrids conjugated with 1,2,3-triazole, including chalcones, flavones, flavanones and flavonols, among others, with antitumor, antimicrobial, antidiabetic, neuroprotective, anti-inflammatory, antioxidant, and antifouling activity have been reported. This review compiles the biological activities recently described for these hybrids, highlighting the mechanism of action and structure-activity relationship (SAR) studies.