Synthesis and antibiotic activity of a small molecules library of 1,2,3-triazole derivatives

Selective Synthesis of 2-(1,2,3-Triazoyl) Quinazolinones through Copper-Catalyzed Multicomponent Reaction

We describe here our results from the copper-catalyzed three component reaction of 2-azidobenzaldehyde, anthranilamide and terminal alkynes, using Et3N as base, and DMSO as solvent. Depending on the temperature and amount of Et3N used in the reactions, 1,2,3-triazolyl-quinazolinones or 1,2,3-triazolyl-dihydroquinazolinone could be obtained. When the reactions were performed at 100 °C using 2 equivalents of Et3N, 1,2,3-triazolyl-dihydroquinazolinone was formed in 82% yield, whereas reactions carried out at 120 °C using 1 equivalent of Et3N provided 1,2,3-triazolyl-quinazolinones in moderate-to-good yields.

Bioactive 1,2,3-Triazoles: An Account on their Synthesis, Structural Diversity and Biological Applications

The triazole heterocycle is a privileged scaffold in medicinal chemistry, since its structure is present in a large number of biologically active molecules, including several drugs currently in the market. Due to their vast applications, a wide variety of methods are described for their preparation, such as the 1,3-dipolar cycloaddition and processes involving diazo compounds and diazo transfer reactions. Considering the significant number of contributions from our research group to this chemistry in recent decades, in this account we discuss both the development of new methods for the synthesis of 1,2,3-triazoles and the preparation of new triazole-functionalized biologically active molecules using classical approaches.

Synthesis and structural characterization of novel O-substituted phenolic and chalcone derivatives with antioxidant activity

A series of novel 4- O-alkyltriazolylphenolic derivatives is first synthesized with good to excellent yields via the click reaction of 3-methoxy-4- O-propargylbenzaldehyde or 3-allyl-4- O-propargylacetophenone and aromatic azide derivatives. Next, the chalcones are prepared via the Claisen-Schmidt method from 4- O-alkylphenylketone derivatives in the presence of the corresponding (hetero)aromatic aldehydes as electrophiles. The structures of the newly synthesized compounds are confirmed from their infrared, nuclear magnetic resonance spectral data, and by elemental analysis. The main advantages of this procedure are the simplicity of the reaction conditions, easily available starting materials, and simple work-up. The antioxidant activity of several of the products is determined using the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) radical scavenging assay. 4- O-propargylvanillin (IC50 = 14.54 µg/mL) had moderate antioxidant activity.

Design and synthesis of 4,5-diphenyl-imidazol-1,2,3-triazole hybrids as new anti-diabetic agents: in vitro α-glucosidase inhibition, kinetic and docking studies

Fourteen novel 4,5-diphenyl-imidazol-1,2,3-triazole hybrids 8a-n were synthesized with good yields by performing click reaction between the 4,5-diphenyl-2-(prop-2-yn-1-ylthio)-1H-imidazole and various benzyl azides. The synthesized compounds 8a-n were evaluated against yeast α-glucosidase, and all these compounds exhibited excellent inhibitory activity (IC₅₀ values in the range of 85.6 ± 0.4-231.4 ± 1.0 μM), even much more potent than standard drug acarbose (IC₅₀ = 750.0 μM). Among them, 4,5-diphenyl-imidazol-1,2,3-triazoles possessing 2-chloro and 2-bromo-benzyl moieties (compounds 8g and 8i) demonstrated the most potent inhibitory activities toward α-glucosidase. The kinetic study of the compound 8g revealed that this compound inhibited α-glucosidase in a competitive mode. Furthermore, docking calculations of these compounds were performed to predict the interaction mode of the synthesized compounds in the active site of α-glucosidase. A novel series of 4,5-diphenyl-imidazol-1,2,3-triazole hybrids 8a-n was synthesized with good yields by performing click reaction between the 4,5-diphenyl-2-(prop-2-yn-1-ylthio)-1Himidazole and various benzyl azides. The synthesized compounds 8a-n were evaluated against yeast α-glucosidase and all these compounds exhibited excellent inhibitory activity (IC50 values in the range of 85.6 ± 0.4-231.4 ± 1.0 μM), even much more potent than standard drug acarbose (IC50 = 750.0 μM).

Synthesis, Molecular Docking, and Preliminary Evaluation of 2-(1,2,3-Triazoyl)benzaldehydes As Multifunctional Agents for the Treatment of Alzheimer's Disease

We described here our results on the use of thiourea as a ligand in the copper catalysed azide-alkyne cycloaddition (CuAAC) of 2-azidobenzaldehyde with alkynes. Reactions were performed reacting 2-azidobenzaldehyde with a range of terminal alkynes using 10 mol % of copper iodide as a catalyst, 20 mol % of thiourea as a ligand, triethylamine as base, DMSO as solvent at 100 °C under nitrogen atmosphere. The corresponding 2-(1H-1,2,3-triazoyl)-benzaldehydes (2-TBH) were obtained in moderated to excellent yields and according our experiments, the use of thiourea decreases the formation of side products. The obtained compounds were screened for their binding affinity with multiple therapeutic targets of AD by molecular docking: β-secretase (BACE), glycogen synthase kinase (GSK-3β) and acetylcholinesterase (AChE). The three compounds with highest affinity, 5 a (2-(4-phenyl-1H-1,2,3-triazol-1-yl)benzaldehyde), 5 b (2-(4-(p-tolyl)-1H-1,2,3-triazol-1-yl)benzaldehyde), and 5 d (2-(4-(4-(tert-butyl)phenyl)-1H-1,2,3-triazol-1-yl)benzaldehyde) were selected and evaluated on its antioxidant effect, in view of select the most promising one to perform the in vivo validation. Due the antioxidant potential ally to the affinity with BACE, GSK-3β and AChE, compound 5 b was evaluated in a mouse model of AD induced by intracerebroventricular injection of streptozotocin (STZ). Our results indicate that 5 b (1 mg/kg) treatment during 20 days is able to reverse the cognitive and memory impairment induced by STZ trough the modulation of AChE activity, amyloid cascade and GSK-3β expression.

Exploring the Chemistry and Therapeutic Potential of Triazoles: A Comprehensive Literature Review

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Triazole is a valuable platform in medicinal chemistry, possessing assorted pharmacological properties, which could play a major role in the common mechanisms associated with various disorders like cancer, infections, inflammation, convulsions, oxidative stress and neurodegeneration. Structural modification of this scaffold could be helpful in the generation of new therapeutically useful agents. Although research endeavors are moving towards the growth of synthetic analogs of triazole, there is still a lot of scope to achieve drug discovery break-through in this area. Upcoming therapeutic prospective of this moiety has captured the attention of medicinal chemists to synthesize novel triazole derivatives. The authors amalgamated the chemistry, synthetic strategies and detailed pharmacological activities of the triazole nucleus in the present review. Information regarding the marketed triazole derivatives has also been incorporated. The objective of the review is to provide insights to designing and synthesizing novel triazole derivatives with advanced and unexplored pharmacological implications.

Design, Synthesis and Cytotoxicity of Novel Coumarin-1,2,3-triazole-1,2,4- Oxadiazole Hybrids as Potent Anti-breast Cancer Agents

Background:

This work reports design, synthesis, and in vitro cytotoxicity of novel coumarin-1,2,3-triazole-1,2,4-oxadiazole hybrids against three breast cancer cell lines MCF-7, MDA-MB-231, and T-47D.

Methods:

Synthetic procedure for the preparation of desired compounds was started from the reaction of coumarins or with propargyl bromide to give O-propargylated coumarins or 5. Then, click reaction between the later compounds and 3-aryl-5-(chloromethyl)-1,2,4-oxadiazoles afforded the desired products in good yields.

Results:

Among the synthesized compounds, 4-((1-((3-(4-chlorophenyl)-1,2,4-oxadiazol-5- yl)methyl)-1H-1,2,3-triazol-4-yl)methoxy)-2H-chromen-2-one (9a) showed the best cytotoxicity against breast cancer cell lines.

Conclusion:

Compound 9a depicted the most activity toward MDA-MB-231 and T-47D cells while compounds 8a and 8c were the most potent compounds against MCF-7.

Click-tailed benzenesulfonamides as potent bacterial carbonic anhydrase inhibitors for targeting Mycobacterium tuberculosis and Vibrio cholerae

A series of 1,2,3-triazole-bearing benzenesulfonamides was assessed for the inhibition of carbonic anhydrases (CA, EC 4.2.1.1) from bacteria Vibrio cholerae (VchCAα and VchCAβ) and Mycobacterium tuberculosis (β-mtCA3). Growing resistance phenomena against existing antimicrobial drugs are globally spreading and highlight a urgent need of agents endowed with alternative mechanisms of action. Two global WHO strategies aim to reduce cholera deaths by 90% and eradicate the tuberculosis epidemic by 2030. The derivatives here reported represent interesting leads towards the optimization of new antibiotic agents showing excellent inhibitory efficiency and selectivity for the target CAs over the human (h) off-target isoform hCA I. In detail, the first subset of derivatives potently inhibits VchCAα in a low nanomolar range (KIs between 0.72 and 22.6 nM). Compounds of a second subset, differing from the first one for the position of the spacer between benzenesulfonamide and triazole, preferentially inhibit VchCAβ (KIs in the range 54.8-102.4 nM) and β-mtCA3 (KIs in the range 28.2-192.5 nM) even more than the clinically used AAZ, used as the standard.

Synthesis, Photophysical, and Antioxidant Properties of Rhodamine B Decorated Novel Dendrimers

Novel triazole bridged dendrimers with rhodamine B derivative as surface groups have been achieved using click chemistry by both divergent and convergent approaches. Rhodamine B decorated dendrimers 1, 2, and 3 were synthesised up to the second generation with spirolactam grafted at the terminal. The UV and fluorescence intensity increases with the increase in the dendritic generation. The synthesised rhodamine B decorated dendrimers show significant antioxidant behaviour compared with the standards butylated hydroxy toluene (BHT) and gallic acid when tested by 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging assay and hydroxyl radical scavenging assay methods, respectively. Rhodamine B decorated higher generation dendrimers exhibit better antioxidant activity than the lower generation dendrimers due to the presence of a greater number of triazole branching units and rhodamine B derivative surface units.

Synthesis and Reactivity of Propargylamines in Organic Chemistry

Propargylamines are a versatile class of compounds which find broad application in many fields of chemistry. This review aims to describe the different strategies developed so far for the synthesis of propargylamines and their derivatives as well as to highlight their reactivity and use as building blocks in the synthesis of chemically relevant organic compounds. In the first part of the review, the different synthetic approaches to synthesize propargylamines, such as A³ couplings and C-H functionalization of alkynes, have been described and organized on the basis of the catalysts employed in the syntheses. Both racemic and enantioselective approaches have been reported. In the second part, an overview of the transformations of propargylamines into heterocyclic compounds such as pyrroles, pyridines, thiazoles, and oxazoles, as well as other relevant organic derivatives, is presented.

Hetero-Diels-Alder reactions of novel 3-triazolyl-nitrosoalkenes as an approach to functionalized 1,2,3-triazoles with antibacterial profile

The generation and reactivity of 3-triazolyl-nitrosoalkenes are reported for the first time. The study showed that hetero-Diels-Alder reaction of these heterodienes is an interesting synthetic strategy to functionalized 1,2,3-triazoles, including 1,2,3-triazolyl-pyrroles, 1,2,3-triazolyl-dipyrromethanes and 1,2,3-triazolyl-indoles. The evaluation of the antibacterial profile against Gram-positive and Gram-negative strains revealed the new 5,5'-diethyldipyrromethane bearing a side chain incorporating a triazole and oxime moieties. The antibacterial profile detected was within the Clinical and Laboratory Standard Institute (CLSI) range and against important Staphylococcus species including Methicillin-resistant strain (S. aureus ATCC 25923, S. epidermidis ATCC 12228 and S. simulans ATCC 27851 and MRSA). Interestingly, this new 1,2,3-triazole presented hemocompatibility and low in silico toxicity profile similar to antibiotics current in use. It also has an usual antibiofilm activity against MRSA, which reinforced its potential as a new antibacterial prototype.

Dibenzyl({1-[(4-methyl-2-phenyl-4,5-dihydro-1,3-oxazol-4-yl)methyl]-1H-1,2,3-triazol-4-yl}methyl)amine

In the title compound, C28H29N5O, the molecule adopts an approximate U-shape, a conformation imposed at least in part by an intramolecular π–π contact between the two five-membered rings, which display a centroid-to-centroid separation of 3.6522 (7) Å. The planes of these rings are inclined to one another by 66.12 (5)°. A weak intramolecular C—H...·N hydrogen bond is also found. The planes of the phenyl rings of the amine unit are inclined at a dihedral angle of 81.10 (4)°, while that of the 4,5-dihydrooxazole ring makes an angle of 11.74 (8)° with its phenyl substituent. The crystal packing is stabilized by C—H...N hydrogen bonds that form chains parallel to thebaxis. Several C—H...π(ring) contacts are also present.

Synthesis and cytotoxicity evaluation of aryl triazolic derivatives and their hydroxymethine homologues against B16 melanoma cell line

In this manuscript we describe synthesis and cytotoxicity evaluation of some triazolic derivatives against B16 melanoma cell line. For this purpose, we transformed a set of aromatic aldehydes into terminal alkynes, using Besthmann-Ohira reagent, and we made the corresponding hydroxymethyl homologated alkynes by an acetylene Grignard reagent. These generated two sets of alkynes were then subjected to a copper(I)-catalyzed alkyne-azide cycloaddition reaction (CuAAC) using a solid-supported catalyst (Amberlyst A-21 CuI), with a third set composed of organic azides. Synthesized triazoles were then tested in vitro against B16 melanoma cell line. Amongst them, compounds a1b1 (R(1) = p-nitrophenyl, R(2) = benzyl), a4b1 (R(1) = naphthyl, R(2) = benzyl) and a4b5 (R(1) = naphthyl, R(2) = (R/S)- dioxolane) showed the best activity against B16 melanoma cells, with IC50 of 5.12, 3.89 and 6.60 μM respectively.

Synthesis and antitumor activity evaluation of lamiridosin A derivatives

A series of lamiridosin A derivatives were synthesized through simple procedures. Their antitumor activities were evaluated against EC9706, MGC803, and B16 cell lines in vitro. Several compounds showed potent antitumor activity, especially compound 10, with IC50 value of 2.36 μmol/L against MGC803 cell lines, is more potent than marketed positive drug 5-fluorouridine (5-FU).

Synthesis, characterization, and antibacterial property of novel starch derivatives with 1,2,3-triazole

Four novel starch-linked-1,2,3-triazole derivatives were synthesized including 6-hydroxymethyltriazole-6-deoxy starch (HMTST), 6-bromomethyltriazole-6-deoxy starch (BMTST), 6-chloromethyltriazole-6-deoxy starch (CMTST), and 6-carboxyltriazole-6-deoxy starch (CBTST). Their antibacterial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were evaluated in vitro, respectively. The inhibitory property of the obtained amphiprotic starch derivatives exhibited a remarkable improvement over starch. And the antibacterial indices of most of the products were higher than 60% and 40% at 1.0 mg/mL when the culture time was 8 h and 16 h, respectively. Moreover, the inhibitory index of CBTST attained 97% above at 1.0 mg/mL. Generally, the inhibitory activity decreased in the order: CBTST>CMTST>BMTST>HMTST>starch. Furthermore, the order of their antibacterial activity was consistent with the electron-withdrawing property of different substituted groups of the 1,2,3-triazole groups. The substituted groups with stronger electron withdrawing ability relatively possessed greater antibacterial activity.

Synthesis and Anti-Tumour Activity Evaluation of Bergenin Derivatives

A series of triazole derivatives of bergenin were synthesised through the nucleophilic substitution reaction of bergenin and propargyl bromide, and following click reaction with different azides. Their antitumour activities were evaluated against EC9706, MGC803 and B16 in vitro. Several compounds showed potent anti-tumour activity, especially (2S,3R,4R,4aS,10bR)-8,10-bis{{1-[4-(tert-butyl)benzyl]-1H-1,2,3-triazol-4-yl} methoxy}-3,4-dihydroxy-2-(hydroxymethyl)-9-methoxy-2,3,4,4a-tetrahydropyrano[3,2-c]isochromen-6(10bH)-one, with IC50 value down to 6.28 μmol L-1 against EC970.

1,2,3-Triazoles from carbonyl azides and alkynes: filling the gap

Electron deficient azides are challenging substrates in CuAAC reactions. Particularly, when N-carbonyl azides are applied the formation of N-carbonyl triazoles has not yet been observed. We report herein the first example of this class of reaction, with a copper-based system that efficiently enables the synthesis of N-carbamoyl 1,2,3-triazoles by [3+2] cycloaddition of N-carbamoyl azides and alkynes.

Multifaceted strategy for the synthesis of diverse 2,2'-bithiophene derivatives

New catalytically or high pressure activated reactions and routes, including coupling, double bond migration in allylic systems, and various types of cycloaddition and dihydroamination have been used for the synthesis of novel bithiophene derivatives. Thanks to the abovementioned reactions and routes combined with non-catalytic ones, new acetylene, butadiyne, isoxazole, 1,2,3-triazole, pyrrole, benzene, and fluoranthene derivatives with one, two or six bithiophenyl moieties have been obtained. Basic sources of crucial substrates which include bithiophene motif for catalytic reactions were 2,2'-bithiophene, gaseous acetylene and 1,3-butadiyne.