Structural modification strategies of triazoles in anticancer drug development

The triazole functional group plays a pivotal role in the composition of biomolecules with potent anticancer activities, including numerous clinically approved drugs. The strategic utilization of the triazole fragment in the rational modification of lead compounds has demonstrated its ability to improve anticancer activities, enhance selectivity, optimize pharmacokinetic properties, and overcome resistance. There has been significant interest in triazole-containing hybrids in recent years due to their remarkable anticancer potential. However, previous reviews on triazoles in cancer treatment have failed to provide tailored design strategies specific to these compounds. Herein, we present an overview of design strategies encompassing a structure-modification approach for incorporating triazoles into hybrid molecules. This review offers valuable references and briefly introduces the synthesis of triazole derivatives, thereby paving the way for further research and advancements in the field of effective and targeted anticancer therapies.

Synthesis of 3,4,5-Trisubstituted 1,2,4-Triazoles via I2-Catalyzed Cycloaddition of Amidines with Hydrazones

A general and practical method for the construction of various 3,4,5-trisubstituted 1,2,4-triazoles via I2-catalyzed cycloaddition of N-functionalized amidines with hydrazones is reported. This strategy features cheap and readily available catalyst and starting materials, broader substrate scope, and moderate-to-good yields. The mechanism study shows that the existence of hydrogen on the nitrogen of hydrazones is crucial for this transformation.

Dearomatization of Pyridines: Stereoselective Synthesis of Functionalized [1,2,4]Triazolo[4,3-a]pyridines

The stereoselective preparation of functionalized [1,2,4]triazolo[4,3-a]pyridines from N-tosylhydrazones and pyridines was developed through the dearomatization of pyridines. The current transformation features good step- and atom-economy, high diastereoselectivity, and the efficient formation of four new carbon-heteroatom bonds in the corresponding product tetrahydro pyridines.

Exploiting the umpolung reactivity of diazo groups: direct access to triazolyl-azaarenes from azaarenes

The present work documents electrophilic substitution of azaarenes, mainly isoquinolines, with hypervalent iodine diazo reagents (HIDR) followed by formal [3+2]-dipolar cycloaddition in a tandem fashion. Other azaarenes viz. pyridines and phenanthridines too could be successfully used in the reaction. The methodology capitalizes on the umpolung nature of α-aryliodonio diazo compounds for installing a nucleophile, i.e. azaarene, at their α-position. Subsequent ylide formation and intramolecular 1,5-cyclization furnished 4,3-fused 1,2,4-triazolyl-azaarenes in good yields. The reaction is notable for its mild conditions, operational simplicity and fairly general scope.

Diversity-Oriented Synthesis of 1,2,4-Triazols, 1,3,4-Thiadiazols, and 1,3,4-Selenadiazoles from N-Tosylhydrazones

The diversity-oriented synthesis of 1,2,4-triazols, 1,3,4-thiadiazols, and 1,3,4-selenadiazoles from N-tosylhydrazones was developed, and the reactions were general for a wide range of substrates, in which NH₂CN, KOCN, KSCN, and KSeCN were used as odorless sources. Two different pathways were proposed, and N-tosylhydrazonoyl chlorides were formed in situ in the presence of NCS.

An overview of the reactions involving azomethine imines over half a decade

Azomethine imines constitute a versatile class of 1,3-dipoles which was used extensively for biologically relevant N-heterocycle synthesis – a five-year recap.

KI/TBHP-promoted [3 + 2] cycloaddition of pyrrolo[1,2-a]quinoxalines and N-arylsulfonylhydrazones

A series of diverse fused [1,2,4]triazolo[3,4-c]quinoxalines was obtained by an efficient KI/TBHP-promoted [3 + 2] cycloaddition of pyrrolo[1,2-a]quinoxalines and N-arylsulfonylhydrazones.

KI-catalyzed oxidative cyclization of α-keto acids and 2-hydrazinopyridines: efficient one-pot synthesis of 1,2,4-triazolo[4,3-a]pyridines

A one-pot approach to 1,2,4-triazolo[4,3-a]pyridines via KI-catalyzed oxidative cyclization was developed with good economical and environmental advantages.

Trivalent Y3+ ionic sensor development based on (E)-Methyl-N'-nitrobenzylidene-benzenesulfonohydrazide (MNBBSH) derivatives modified with nafion matrix

(E)-Methyl-N'-nitrobenzylidene-benzenesulfonohydrazide (MNBBSH) compounds were synthesized using a condensation procedure from the derivatives of nitrobenzaldehyde and 4-Methyl-benzenesulfonylhydrazine, which crystallized in ethanol and methanol as well as characterized by FTIR, UV-Vis, 1H-NMR, and 13C-NMR. MNBBSH structure was confirmed using a single crystal X-ray diffraction technique and used for the detection of selective yttrium ion (Y3+) by I-V system. A thin layer of MNBBSH was deposited onto a glassy carbon electrode (GCE) with 5% nafion for the sensitive and selective Y3+ sensor. The modified MNBBSH/GCE sensor is exhibited the better electrochemical performances such as sensitivity, limit of detection (LOD), linear dynamic range (LDR), limit of quantification (LOQ), short response time, and long term storage ability towards the selective metal ion (Y3+). The calibration curve of 2-MNBBSH/GCE sensor was plotted at +1.1 V over a broad range of Y3+ concentration. Sensitivity, LOD, LDR and LOQ of the fabricated sensor towards Y3+ were calculated from the calibration curve and found as 1.90 pAμM-1 cm-2, 10.0 pM, 1.0 nM~1.0 mM and 338.33 mM respectively. The 2-MNBBSH/Nafion/GCE sensor was applied to the selective determination of Y3+ in spiked samples such as industrial effluent and real water samples from different sources, and found acceptable and reasonable results.