Diazo Coupling Reaction Research Articles

Live Cell Imaging Studies on Orange Emitting Thiazole-Pyridone Azo Fluorophore and Its Latent Fingerprints, Computational, Electrochemical Sensing for Dopamine Detection.

The fluorescent materials have sparked a lot of research interests due to their unique electronic, optical and chemical characteristics. Here, we are intended to present a simple and facile synthesis of novel orange emitting thiazole-pyridone fluorescent tag (TPFT) by a simple diazo coupling reaction and the structural elucidation was carried out by IR, NMR (1H and 13C), UV-Vis, photoluminescence and HR-MS spectrometry. The solvatochromic behaviour of the TPFT offered crucial information about the formation of hydrazone and azo tautomeric forms. The DFT simulations are computed to calculate HOMO-LUMO energy gap (3.028 eV) of TPFT along with MEP and RDG analyses. Comprehensive LFP visualization is revealed under both normal and UV light conditions (365 nm). The cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to analyse the electrochemical behaviour of the TPFT-modified glassy carbon electrode (MGCE) and exhibited a lower detection limit of 7.89 × 10-8 M (S/N = 3) with a linear range of 0.5-8.0 μM for DA detection. The live-cell imaging study of TPFT showed a strong blue emission at 453 nm, which generally indicates the existence of fluorescence stability.

High permeance of polyamide nanofiltration membranes with porous organic polymers interlayers based on diazo coupling reaction

Nanofiltration (NF) membranes are widely used in many fields, including food, petrochemical and brackish water desalination. One of the challenges for preparing NF membranes is to make NF membranes with high both permeability and selectivity because of the “trade-off" effect. To weaken or break through the “trade-off" effect, the thin film composite (TFC) NF membranes with high permeability and selectivity were prepared by constructing porous organic polymers (POPs) interlayers via diazo coupling reaction in the wild condition. The effects of the monomers ratio used to prepare POPs interlayers on the separation performance of the as-prepared TFC NF membranes as well as on the surface characteristics of substrate and polyamide (PA) separation layer were investigated. Due to hydrogen bonding, the POPs interlayers with hydroxyl groups slow down the diffusion rate of PIP molecules, which changes the surface structure of the polyamide (PA) separation layer from the nodular structure to the folded structure that favors increased permeability. The pure water permeance of the optimal TFC-S4 membrane (47.5 ± 0.3 L m−2 h−1 bar−1) is 3.8 times higher than that of the commercial polyamide nanofiltration membrane NF270 (12.5 L m−2 h−1 bar−1). Na2SO4 rejection of the TFC-S4 membrane is 98.7 ± 0.1 %, which is greater than that of NF270 (96 %). This study provides ideas for future applications of POPs materials in NF membranes desalination.

Carbon dots-based dual-mode sensor for highly selective detection of nitrite in food substrates through diazo coupling reaction

As an antioxidant and preservative agent, nitrite (NO2−) plays an essential role in the food industry to maintain freshness or inhibit microbial growth. However, excessive addition of NO2− is detrimental to health, so accurate and portable detection of NO2− is critical for food quality control. Notably, the selectivity of most carbon dots (CDs)-based fluorescence sensors was not enough due to the nonspecific interaction mechanism of hydrogen bond, electrostatic interaction and inner filter effect etc. Herein, a novel fluorescence/UV–vis absorption (FL/UV–vis) dual-mode sensor was developed on basis of mC-CDs, which were prepared by simple solvothermal treatment of m-Phenylenediamine (m-PDA) and cyanidin cation (CC). The fluorescence of these mC-CDs could be selectively responded by NO2− through the specific diazo coupling reaction between NO2− and amino groups on the surface of mC-CDs, thus effectively improving the selectivity of NO2− detection. The CDs-based fluorescence sensor possessed a low detection limit of 0.091 μM and 0.143 μM for FL and UV–vis methods and the excellent linear range of 0.0–60.0 μM. Furthermore, the mC-CDs sensor was employed to detect NO2− in real samples with a recovery rate of 97.11 %–104.15 % for quantitative addition. Moreover, the smartphone-assisted fluorescence sensing platform developed could identify the subtle color changes that could not be distinguished by the naked eye, and had the advantages of fast detection speed and intelligence. More importantly, the portable solid phase sensor based on mC-CDs had been successfully applied to the specific fluorescence identification and concentration monitoring of NO2−. Accordingly, the designed sensor provided a new strategy for the highly selective and convenient sensing of NO2− in food substrates, and paved the way for the wide application of CDs-based nanomaterials in the detection of food safety.

Preparation, in vitro and in silico antioxidant and antibacterial studies of 4-aminoacetanilide azo derivatives

A new series of new 4-aminoacetanilide azo derivatives 1–13 were successfully synthesised via a diazo coupling reaction and gave a good to excellent yield of 73 %–93 %. The antioxidant capabilities of the series 1–13 screened through 2,2′-diphenyl-1-picrylhydrazyl (DPPH) assay and ferric reducing antioxidant power (FRAP) assay showed promising data of 12.6–199.4 ppm and 12.65–210.9 mg/ml Trolox equivalent, respectively. The findings supported by in silico docking analysis targeted Heme oxygenase-1 (HO-1) evidenced by a binding score of – 7.2 to – 8.2 kcal/mol outperforming the standard, ascorbic acid scoring only – 5.7 kcal/mol. Among all, compound 11 displayed the highest antioxidant potential with IC25 of 12.6 ppm against DPPH assay and 210.9 mg/ml Trolox for FRAP assay believed owing to the presence of methoxy group at ortho position in the phenolic compound that effectively lowered the ionisation potential and high up energy of highest occupied molecular orbital (HOMO). Nevertheless, the antibacterial potential of the series screened through the Kirby-Bauer disc diffusion method against Escherichia coli and Staphylococcus aureus showed no antibacterial activity postulated due to the presence of amide and acetyl group restricted the ability of the compound to form an interaction with the protein receptor of bacteria tested. This study provided new insight into the development of dual-functional drugs for non-communicable diseases and antimicrobial resistance.

Chemical modification of marigold (Tagetes erecta) dye via diazo-coupling reaction for enhanced dyeing on polyester: A sustainable approach

Plant-derived natural extracts contain large amounts of polyphenolic compounds, presenting opportunities for chemical modification. The present study deals with the extraction of dye from Marigold (Tagetes erecta), a widely cultivated and commercially utilised flower, using water as an extraction medium followed by its chemical modification for sustainable synthesis of yellow dye and dyeing of polyester fabric. Phytochemical analysis and FTIR spectroscopy of the natural dye extract from Marigold flowers indicated the presence of polyphenolic flavonoids. The water-extracted natural dye was subsequently chemically modified with aniline, a primary aryl amine, via diazotisation and coupling reactions to yield a semi-synthetic natural dye with a 1.2 ± 0.3 g yield. The major constituents in the marigold natural extract and the Modified Marigold Extract (MME) dye were characterised using High-Resolution Liquid Chromatography-Mass Spectrometry (LC-HRMS). The marigold water extract contained a high concentration of Gossypetin 8-Glucoside, a yellow-coloured flavonoid compound with a mass-to-charge ratio (m/z) of 480.0904. LC-HRMS analysis further confirmed the presence of a constituent (m/z 424.0485) in the MME dye, corresponding to the predicted mass of chemically modified Gossypetin 8-Glucoside. The MME dye was subsequently employed for dyeing polyester fabric, exhibiting maximum colour strength at 10 % shade under acidic condition. The dyeing performances of the MME-dyed fabrics were evaluated in terms of fastness and post-dyeing strength. This study demonstrates a unique and novel approach to develop a yellow semi-synthetic natural dye, emphasising its potential utility for polyester dyeing.

Synthesis, computational and UV–Vis absorption studies of novel sulfathiazole azo sulfonamides acting as potent antitubercular agents

In this work, we have reported the synthesis of unprecedented sulfonamide azo dyes 4(a-j) by the diazo-coupling reaction of sulfathiazole with various coupling components. Different spectroscopic techniques, like FT-IR, NMR (1H and 13C), and HRMS, were used to precisely assess the structures of the target molecules. The UV–Vis absorption study was conducted using variety of organic solvents. Quantum chemical calculations, geometrical optimization, and molecular electrostatic potential regions of all sulfathiazole azo colorants were explored using (DFT)/B3LYP method. The efficacy of the synthesized dyes in combatting M. tuberculosis was examined using the MABA assay; the derivatives 4c and 4h demonstrated promising activity with MIC of 1.56 µg/mL. Further, in silico molecular docking study was performed to elucidate the interactions with enoyl-ACP reductase. Target compounds were screened for their antimicrobial activity using the broth microdilution method against two gram-positive, two gram-negative bacterial strains, and a fungal strain. The cytotoxic potential of the active compounds was assessed using the MTT assay against the Vero cell line.

Mild and friendly preparation of a high-surface porous organic polymers and its application for sensitive detections of endocrine disrupting chemicals

For sample pretreatment technique, the preparation of a stable, practical material with excellent enrichment performance is the core, and especially the preparation of an environmentally friendly adsorbent is desired. The preparation of most materials involves the use of organic solvents, which puts a strain on the environment to a certain extent, and the choice of aqueous solution as the reaction environment for the diazo-coupling reaction has attracted great attention, as a friendly strategy. We prepared the environmentally friendly porous organic polymer (POP) 2,4,6-tris(2,4,6-trihydroxyphenyl)-1,3,5-triazine-4,4′-diaminobiphenyl (CTT-BD) by diazo-coupling reaction, and further fabricated as stable solid phase microextraction (SPME) fiber. It achieved efficient extraction of derivatized bisphenol endocrine disrupting chemicals (EDCs) from water samples with enrichment factors ranging from 1306 to 2781. Under the optimum experimental conditions, the developed method by combining the CTT-BD coated fiber with gas chromatography mass spectrometry (GC–MS), demonstrated a wide linearity (10–10000 ng/L), low limits of detection (2.0–3.0 ng/L) and good reproducibility (relative standard deviations 3.1–8.1 %). Finally, the proposed method has been successfully used for the determinations of EDCs from water samples, and satisfactory recoveries (85.6–118.0 %) were achieved.

Photophysical and antitubercular studies on newly synthesised structurally architectured sulphonamide

This study presents the synthesis and characterisation of four mono-azo sulphonamide derivatives through diazo-coupling electrophilic substitution reactions. The structural analysis of the synthesised molecules was conducted utilising FT-IR, 1H-NMR and HR-MS techniques. Absorption and fluorescence maxima of the synthesised molecules were determined across solvents of varying polarity to explore Solvatochromic behaviour. Density functional theory was employed to elucidate electronic and optical properties, including the computation of HOMO–LUMO energies using Gaussian 09W software, with comparisons to experimental data. Molecular electrostatic potential 3D plots identified electrophilic and nucleophilic sites. Solvent interactions were evaluated using Kamlet–Abboud Taft and Catalan parameters. Further, global chemical reactivity descriptors were estimated to ascertain chemical reactivity of the molecules. Additionally, the effectiveness of the colourant anti-tubercular activity was evaluated using in vitro and molecular docking techniques. The biological activity results reveal that methyl-pyridone and barbituric acid coupled with sulphamethizole (SMP and SMB) displayed excellent anti-tubercular activity compared with the standard Gentamycin.

Synthesis, characterization of new electrochemical activated sulfadiazine azo dyes and its theoretical studies with LFPs, antioxidant application

The present study describes the optoelectronic, LFPs visualizations and DPPH scavenging activity using sulfadiazine azo dyes. The resulting azo product was obtained through a diazo-coupling reaction of sulfadiazine with different coupling compounds under ambient experimental conditions and confirmed through IR, 1H NMR, 13C NMR, LC-MS, and UV–Vis spectroscopic techniques. The computational studies were investigated using the B3LYP/6–311 + g(d,p) basis set in the Gaussian 09 W program at the gaseous phase. Electrochemical behavior was analyzed for synthesized compounds and fine redox peaks at increasing scan rates in the CH instrument. In addition, experimental calculations of HOMO-LUMO energies were conducted using electrochemical redox on set potentials and compared with theoretical values. Further, a latent fingerprint application for azo derivatives was developed using the powder dusting method, resulting in clear visuals of level I whorl and level Ⅱ bifurcation and eye ridge finger marks registered in normal and UV light. Compound 3b exhibited excellent DPPH scavenging activity (IC50 = 172.04 µg). In silico docking simulations were done for the synthesized azo compounds using the antioxidant enzyme, human peroxiredoxin5 (1HD2) as a receptor. In silico study of the designed azo dye compounds exhibit enormous binding energy (-6.6, −6.5, −6.4 kcl/mol) in comparison with the standard drug (-5.7 kcl/mol). docking results were closely linked to the experimental DPPH scavenging activity.

Synthesis, Spectroscopic, Computational, and Biological Evaluation of Pyrazole mono azo dyes

In the present work, a series of new dispersed mono azo dyes (3) were synthesized through conventional diazo-coupling reaction between 4-hydroxy-phenylacetamide with pyrazole derivatives at low temperature. All the synthesized mono azo compounds were characterized by various spectroscopic methods like IR, NMR, electronic spectral, LC-MS, and fluorescence spectral studies. The experimental IR data was compared with that of the theoretical data and it has been observed that, the experimental IR spectral values are found to be lower than that of the theoretical values. The quantum chemical calculations were also carried out to understand the chemical reactivity of the compounds by using B3LYP method in conjugation with 6-311++G (d, p) basis set. The compounds were screened for anti-tuberculosis properties against M. tuberculosis and the compound 7 was found to exhibit a significant inhibitory effect with MIC value of 12.5μg/mL. The anti-microbial studies were carried for synthesized mono azo compounds. Further, the in silico molecular docking study was carried out to know the significant interaction of the synthesized compounds against VEGFR2 target protein.

A facile approach to fabricate dual-responsive smart natural fibre sensors

Smart textiles with the characteristics of lightweight, flexibility, deformability, and breathability have been around for some decades. Although natural fibres have these qualities naturally, the intelligence of natural fibres is still a challenge. This study provides a facile approach to prepare dual-responsive natural cellulose and wool fibres based on reversible acidichromic and photoisometric water-soluble polymeric dye. An acidichromic and photoiscomeric waterborne polyurethane reactive dye (PUD) with the chromaticity, further reactive groups, and waterborne macromolecular structure was first designed and subsequently synthesized via a diazo coupling reaction between a polyurethane precursor (PUP) and a para-ester diazonium salt (PDS). The synthesized PUD with the characteristics of a polyurethane backbone, azobenzene chromophore, β-sulfatoethylsulfone reactive groups, and waterborne sodium sulfate groups was applied in dying of natural fibre products including cotton, ramie and wool fibres with an excellent colour fastness. The PUD possesses a thermal stability and solvent resistance. The synthesized PUD and its dyed natural fibres displayed the acidichromic and photoisomeric behaviours. The maximum absorption peak of the PUD aqueous solution shifted from 442 nm to 503 nm due to the structural transition changing from diazo to hydrazone when the pH values were adjusted from 7 to 1. Meanwhile, the colour of PUD aqueous solution and its dyed cotton, ramie and wool fibres reversibly changed from yellow to red upon pH changing from 7 to 1. With being exposed to 365 nm UV light, the trans-isomers in PUD slowly transformed into cis-isomers with an isomerization rate of 7.68 × 10−5 s−1. The stimuli-responsive polyurethane reactive dye can be a promising candidate for the design of a wearable and flexible natural fibre sensors aiming for monitoring the changes of environment. Furthermore, the conductive and rheological behaviours of PUD aqueous solution exhibited a promising application in the preparation of smart textile sensors via ink-jet printing technique.

Bistate-type ion storage of azo polymer for aqueous zinc ion battery

Azo organic molecules are emerging as promising electrode candidates for energy storage systems due to their high theoretical specific capacity and excellent kinetic performance. In general perception, conventional azo organic small molecules used as cathode material in aqueous batteries remain a challenge because of the poor cycling stability in aqueous electrolytes. Herein, azo organic polymers (AOPs) were synthesized using a diazo-coupling reaction under mild conditions and developed as cathode materials for aqueous zinc-ion batteries. Owing to the long conjugate structure, the AOPs afford extra-long stability with outstanding cyclability of >1000 cycles at 2 A g−1, a comparable capacity (170 mAh g−1 at 0.5 A g−1), and excellent rate performance from 0.5 g−1 to 10 A g−1 in aqueous electrolytes. Significantly, the hydroxyl oxygen and azo functional groups on AOPs can spontaneously form metal heterocyclic complexes with zinc ions in 1 M Zinc trifluoromethanesulfonate (Zn(OTF)2) electrolyte, leading to a notable increase in voltage (by 0.2 V) and capacity (by 43 mAh g−1 at a current density of 2 A g−1) in aqueous zinc-ion battery. Additionally, mechanistic analysis reveals that the AOPs are an active material for bistate storage of zinc ions during the charging and discharging process. The AOPs not only store zinc ions in fully charged state by forming metal heterocyclic complexes but also store zinc ions by a redox reaction between azo functional groups and zinc ions at the discharge process. The results put forward a novel storage mechanism for zinc ions and will pave the way for AOPs’ development in aqueous batteries.

Synthesis, recovery, and application of environmentally friendly disperse dyes with high light fastness

Dye wastewater has attracted great attention due to high pollution and toxicity which can cause harm to the living environment. It is common for azo-disperse dyes to be used to dye hydrophobic fibers. A reduction clearing method is used to eliminate the dye particles on the fabric after dyeing. However, when azo disperse dyes on the fiber surface are eliminated by the reduction clearing process, this can give rise to an effluent discharge due to the presence of sodium hydrosulfite. The introduction of carboxylic ester groups into dye molecules can effectively avoid this issue. Six novel environmentally friendly alkali-clearable disperse dyes, containing cyano and carboxylic ester groups, were readily synthesized by a diazo coupling reaction with various diazo components. Their dyeing properties on polyethylene terephthalate fabrics were respectively measured and compared with those of commercial reference dyes. It was indicated that some fastness properties of the synthesized dyes on polyethylene terephthalate fabrics after the alkali clearing were improved compared with those of the reference dyes due to the existence of the carboxylic ester group. Moreover, the chromaticity of dye wastewater can be further reduced by recovering hydrolyzed dyes.

Green construction of magnetic azo porous organic polymer for highly efficient enrichment and detection of phenolic endocrine disruptors

Porous organic polymers (POPs) are prominent sorbents for effective extraction of endocrine disrupting chemicals (EDCs). However, green and sustainable construction of functional POPs is still challenging. Herein, we developed a magnetic azo POP (Mazo-POP) for the first time using hydroxy-rich natural kaempferol and low-toxic basic fuchsin as monomers through a diazo coupling reaction. The Mazo-POP exhibited excellent extraction capabilities for EDCs with a phenolic structure. Consequently, it was used as a magnetic sorbent for extracting phenolic EDCs from water and fish samples, followed by ultrahigh-performance liquid chromatography-tandem mass spectrometric detection. The Mazo-POP based analytical method afforded a good linearity of 0.06–100 ng mL−1 and 0.3–500 ng g−1 for water and fish samples respectively, with detection limits (S/N = 3) of 0.02–0.5 ng mL−1 and 0.1–1.5 ng g−1, respectively. The method recovery was from 85.2% to 109% and relative standard deviation was less 5.3%. Moreover, the effective adsorption was mainly contributed by hydrogen bond, π-π interaction, pore filling and hydrophobic interaction. This work not only provides an efficient method for sensitive determination of phenolic EDCs, but also highlights the significance of green preparation of environmentally friendly sorbents for enriching/adsorbing pollutants.

Synthesis, antibacterial potential and in silico molecular docking analysis of triazene compounds via diazo coupling reactions of an amine

In the drug discovery and development process, structure-based drug design is essential to ensuring the effectiveness and efficiency of the drugs towards the target receptor. The preparation of a compound with the structural capability to form strong interactions with the receptor is predicted to have stronger therapeutic activity. Herein, a series of N-coupling aromatic triazene compounds 1–13, bearing electron-withdrawing and electron-donating groups at ortho, meta, and para positions were successfully synthesized via diazo coupling reactions of substituted anilines with 4′-aminoacetanilide with reasonable yields of 15–60 %. The antibacterial potential of the compounds was screened against Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) employing the turbidimetric kinetic method, which showed promising minimum inhibitory concentration (MIC) values of 62–185 ppm and 63–158 ppm, respectively. Among all, compounds 1 (H) and 4 (p-F) exhibited excellent bacterial inhibition against both screened bacteria, 83 ppm and 68 ppm (S. aureus) and 63 ppm and 84 ppm (E. coli), respectively outperforming the standard ampicillin 85 ppm (S. aureus) and 86 ppm (E. coli). The in silico molecular docking analysis targeted Dehydrosqualene synthase (CrtM) and DNA gyrase enzymes, which demonstrated binding scores of −8.1 kcal/mol and −8.9 kcal/mol for compound 1 and −8.2 kcal/mol and −8.5 kcal/mol for compound 4, respectively.

Hydrophobic Bombyx mori Silk Fibroin: Routes to Functionalization with Alkyl Chains

AbstractBombyx mori silk fibroin (SF) is a very versatile biopolymer due to its biocompatibility and exceptional mechanical properties which make possible its use as a functional material in several applications. SF can be modified with a large variety of chemical approaches which endow the material with tailored chemical–physical properties. Here, a systematic investigation of different routes is reported to graft long alkyl chains on SF based on both liquid‐ and solid‐phase, aiming to modulate its hydrophobic behavior. The liquid phase method involves direct activation of SF tyrosine residues via diazo coupling and cycloaddition reactions, generating hydrophobic materials insoluble in any common solvent. The solid phase approach consists of the chemical modification of drop‐casted SF films by esterification of hydroxyl groups of serine, threonine, and tyrosine SF residues with acyl chlorides of fatty acids. For the solid‐state functionalization, a new class of hydrophobic pendant groups is synthesized, based on triple esters of gallic acid anhydrides, that are reacted with the biopolymer to further enhance its resulting hydrophobic features.

Color based spectrophotometric determination of vericiguat using diazo coupling reaction; assisted computational calculations

A novel spectrophotometric method aided by computational techniques has been developed to determine vericiguat, a soluble guanylate cyclase stimulator used for reducing the risk of heart failure and cardiovascular mortality. Using density functional theory calculations, 8-hydroxyquinoline was identified as the best coupling agent for the spectrophotometric determination of vericiguat. The method involves the creation of a red-colored chromogen by combining vericiguat with sodium nitrite to form a diazonium ion, which then reacts with 8-hydroxyquinoline. The resulting complex exhibits distinct absorption peaks at 515 nm. Various factors influencing the diazotization process were investigated, and the concentration range of 1–12 μg/mL vericiguat was found to adhere to Beer's law. Job's plot analysis revealed a 1:1 stoichiometric ratio between vericiguat and 8-hydroxyquinoline. This reaction formed the basis for determining vericiguat spectrophotometrically, both in its pure form and in pharmaceutical formulations. Additionally, an analytical greenness metric was employed to evaluate the environmental friendliness of the proposed procedure. The results demonstrated that the method aligns with established values of green analytical chemistry metrics.

Kinetic Measurement and Modeling of a Slow-Rate Diazo Coupling Reaction

Kinetic Measurement and Modeling of a Slow-Rate Diazo Coupling Reaction

Spectrophotometric and smartphone-based facile green chemistry approach to determine nitrite ions using green tea extract as a natural source

In this research, it is aimed to develop an alternative, facile, functional, non-toxic, low-cost, and eco-friendly new spectrophotometric and smartphone-based green analytical methods for the quantitative sensing of nitrite. One of the important features of this research is enabling the use of two portable instruments for field analysis, especially the option of using a smartphone that is inexpensive and accessible to everyone compared to bulky instruments. The proposed method is based on a diazo-coupling reaction of catechin-rich phenolic compounds found in green tea extract with p-Aminobenzoic acid (PABA) in the presence of an acidic medium and NO2−. Under optimal conditions, calibration equations were obtained by utilizing the color intensity increase of the yellow water-soluble azo dye in direct proportion to the increasing NO2− concentration. The analytical response of the developed spectrophotometric method exhibited linearity in the concentration range of 0.2−1.1 mg L−1 at the wavelength of 440 nm with the LOD and LOQ values of 0.05 mg L−1 and 0.15 mg L−1, respectively. For the smartphone-based method, between absorbance obtained from B values and increasing NO2− concentration gave a linearity in the concentration range of 0.05−0.8 mg L−1 with the LOD and LOQ values of 0.017 mg L−1 and 0.050 mg L−1, respectively. The potential interfering effect of common water ions was investigated and also interference of Fe2+ was easily eliminated using Na2EDTA. Validation was performed at a 95% confidence level against the current reference and the Griess reference methods by applying both developed methods to real water samples.

Synthesis, Characterization and Antibacterial study of some 1, 3, 4- thiadiazole ring appended azo derivatives

A series of 1,3,4-thiadiazole ring appended azo derivatives were synthesized in good yields via diazo coupling reaction between 5-(4-substituted)-1,3,4-thiadiazole-2-amine and some active methyline compounds such as dimedone and acetylacetone. All the synthesized compounds were characterized by FT-IR and 1HNMR spectroscopic methods. Further, all synthesized compounds were screened for the antibacterial activity against gram negative bacteria (Escherichia coli, Pseudomonas aruginosa, Shigella boydii) and gram-positive bacteria (Staphylococcus aureus, Bacillus megaterium). The thiadiazole ring appended azo derivative containing a chloro group showed potent activity against Shigella boydii (67.85%) and Staphylococcus aureus (78.57%) and the compound having a nitro group in its structure exhibited maximum zone of inhibition against Staphylococcus aureus (89.28%) and Shigella boydii (82.14%).