New 1,2,3-Triazole-genipin Analogues and Their Anti-Alzheimer's Activity

Genipin, a natural blue colorant precursor: Source, extraction, properties, and applications

Natural cross-linkers are extensively employed due to their low toxicity and biocompatibility benefits. Genipin acts as a precursor for producing blue colorants. The formation of these colorants involves the cross-linking reaction between genipin and primary amines present in amino acids, peptides, and proteins. Genipin is extracted from Gardenia jasminoides and Genipa americana. This article explains the cross-linking mechanism of genipin with proteins/polysaccharides to provide an overall understanding of its properties. Furthermore, it explores new sources of genipin and innovative methodologies to make the genipin recovery process efficient. Genipin increases food products' texture, gel strength, stability, and shelf life. The antibacterial, anti-inflammatory, and antioxidant properties of chitosan, gelatin, alginate, and hyaluronic acid increased after genipin cross-linking. Lastly, drawbacks, toxicity, and directions regarding the genipin cross-linking have also been addressed. The review article covers how to recover and cross-link genipin with biopolymers for industrial applications.

Synthesis and evaluation of photophysical, electrochemical, and ROS generation properties of new chalcogen-naphthoquinones-1,2,3-triazole hybrids

This study presents a comprehensive analysis encompassing the synthesis, structural elucidation, photophysical behavior, and electrochemical properties of a novel series of chalcogen-naphthoquinone-1,2,3-triazole hybrids. Employing a meticulously designed protocol, the synthesis of these hybrids, denoted as 11a-j, was achieved with remarkable efficiency (yielding up to 81%). This synthesis used a regioselective copper-catalyzed azide-alkyne cycloaddition reaction (CuAAC). Furthermore, a detailed investigation into the photophysical characteristics, TDDFT calculations, electrochemical profiles, and photobiological attributes of compounds 11a-j was conducted. This exploration aimed to unravel insights into the excited state behaviors of these molecules, as well as their redox properties. Such insights are crucial for future applications of these derivatives in diverse biological assays.

Pathogenesis of Alzheimer's Disease and Diversity of 1,2,3-Triazole Scaffold in Drug Development: Design Strategies, Structural Insights, and Therapeutic Potential

Alzheimer's disease is a most prevalent form of dementia all around the globe and currently poses a significant challenge to the healthcare system. Currently available drugs only slow the progression of this disease rather than provide proper containment. Identification of multiple targets responsible for this disease in the last three decades established it as a multifactorial neurodegenerative disorder that needs novel multifunctional agents for its management and the possible reason for the failure of currently available single target clinical drugs. 1,2,3-Triazole is a miraculous nucleus in medicinal chemistry and the first choice for development of multifunctional hybrid molecules. Apart from that, it is an integral component of various drugs in clinical trials as well as in clinical practice. This review is focused on the pathogenesis of Alzheimer's disease and 1,2,3-triazole containing derivatives developed in recent decades as potential anti-Alzheimer's agents. The review will provide (A) precise insight of various established targets of Alzheimer's disease including cholinergic, amyloid, tau, monoamine oxidases, glutamate, calcium, and reactive oxygen species hypothesis and (B) design hypothesis, structure-activity relationships, and pharmacological outcomes of 1,2,3-triazole containing multifunctional anti-Alzheimer's agents. This review will provide a baseline for various research groups working on Alzheimer's drug development in designing potent, safer, and effective multifunctional anti-Alzheimer's candidates of the future.

Review of triazole scaffolds for treatment and diagnosis of Alzheimer's disease

Triazole scaffolds, a series of 5-membered heterocycles, are well known for their high efficacy, low toxicity, and superior pharmacokinetics. Alzheimer's disease (AD) is the first neurodegenerative disorder with complex pathological mechanisms. Triazole, as an aromatic group with three nitrogen atoms, forms polar and non-polar interactions with diverse key residues in the receptor-ligand binding procedure, and has been widely used in the molecular design in the development of anti-AD agents. Moreover, considering the simple synthesis approaches, triazole scaffolds are commonly used to link two pharmacodynamic groups in one chemical molecule, forming multi-target directed ligands (MTDLs). Furthermore, the click reaction between azide- and cyano-modified enzyme and ligand provides feasibility for the new modulator discovery, compound tissue distribution evaluation, enzyme localization, and pharmacological mechanism study, promoting the diagnosis of AD course.

1,2,3-Triazoles and their metal chelates with antimicrobial activity

The emergence of drug-resistant bacterial and fungal pathogens has highlighted the urgent need of innovative antimicrobial therapeutics. Transition metal complexes with biologically active ligands (coumarins, terpyridines, triazoles, uracils, etc.) have long been investigated for antimicrobial activity. 1,2,3-Triazoles and their molecular derivatives are well known for a plethora of physiological activities, including antibacterial and antifungal. The aim of the present mini-review is to inform the reader about research conducted on potential antimicrobial 1,2,3-triazole complexes with transition metals. What the authors find surprising is how little such research and experimentation has actually been performed and reported in scientific literature. The goal is to highlight research efforts up to now and impress upon the reader the vast perspectives for novel, effective medicinal substances hidden in this yet unexplored field.

Design, synthesis, and cytotoxic evaluation of quinazoline derivatives bearing triazole-acetamides

A novel series of quinazoline-based agents bearing triazole-acetamides 8a-l were designed and synthesized. All the obtained compounds were tested for in vitro cytotoxic activities against three human cancer cell lines named HCT-116, MCF-7, and HepG2, as well as a normal cell line WRL-68 after 48 and 72 h. The results implied that quinazoline-oxymethyltriazole compounds exhibited moderate to good anticancer potential. The most potent derivative against HCT-116 was 8a (X = 4-OCH₃ and R = H) with IC₅₀ values of 10.72 and 5.33 μM after 48 and 72 h compared with doxorubicin with IC₅₀ values of 1.66 and 1.21 μM, respectively. The same trend was seen in the HepG2 cancerous cell line in which 8a recorded the best results with IC₅₀ values of 17.48 and 7.94 after 48 and 72 h, respectively. The cytotoxic analysis against MCF-7 showed that 8f with IC₅₀ = 21.29 μM (48 h) exhibited the best activity, while compounds 8k (IC₅₀ = 11.32 μM) and 8a (IC₅₀ = 12.96 μM), known as the most effective cytotoxic agents after 72 h. Doxorubicin as positive control exhibited IC₅₀ values of 1.15 and 0.82 μM after 48 and 72 h, respectively. Noteworthy, all derivatives showed limited toxicity against the normal cell line. Moreover, docking studies were also presented to understand the interactions between these novel derivatives and possible targets.

An Overview of 1,2,3-triazole-Containing Hybrids and Their Potential Anticholinesterase Activities

Acetylcholine (ACh) neurotransmitter of the cholinergic system in the brain is involved in learning, memory, stress responses, and cognitive functioning. It is hydrolyzed into choline and acetic acid by two key cholinesterase enzymes, viz., acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). A loss or degeneration of cholinergic neurons that leads to a reduction in ACh levels is considered a significant contributing factor in the development of neurodegenerative diseases (NDs) such as Alzheimer's disease (AD). Numerous studies have shown that cholinesterase inhibitors can raise the level of ACh and, therefore, enhance people's quality of life, and, at the very least, it can temporarily lessen the symptoms of NDs. 1,2,3-triazole, a five-membered heterocyclic ring, is a privileged moiety, that is, a central scaffold, and is capable of interacting with a variety of receptors and enzymes to exhibit a broad range of important biological activities. Recently, it has been clubbed with other pharmacophoric fragments/molecules in hope of obtaining potent and selective AChE and/or BuChE inhibitors. The present updated review succinctly summarizes the different synthetic strategies used to synthesize the 1,2,3-triazole moiety. It also highlights the anticholinesterase potential of various 1,2,3-triazole di/trihybrids reported in the past seven years (2015-2022), including a rationale for hybridization and with an emphasis on their structural features for the development and optimization of cholinesterase inhibitors to treat NDs.