2-thiophenecarboxylic Acid Hydrazide Research Articles

Thiophene appended schiff base probe for selective ‘turn-on’ response for copper (ii) ion and their applications in live cell imaging Thiophene appended schiff base probe for selective ‘turn-on’ response for copper (ii) ion and their applications in live cell imaging

In this research, we have synthesized a thiophene Schiff base from 5-phenyl thiophene-2-carboxaldehyde and 2-thiophene carboxylic acid hydrazide and characterized by using FT-IR NMR, HRMS and SC-XRD analysis techniques. The probe exhibited a selective turn-on fluorescence response for Cu2+ over 20 other common metal ions in a CH3CN (9:1, v/v) solution. The Job’s plot represents a 1:1 binding complexation mode and further DFT study was carried out to aid in understanding the geometric structure and interaction of the ligand and Cu2+. The detection limit (LOD) and limit of quantification (LOQ) were found to be 20 nM and 69 nM respectively. Furthermore, the probe’s sensing ability was tested in HeLa cells and their fluorescence imaging also supported the effective turn-on response towards Cu2+ ion.

Adaption of the ex vivo mycobacterial growth inhibition assay for use with murine lung cells

In the absence of a correlate(s) of protection against human tuberculosis and a validated animal model of the disease, tools to facilitate vaccine development must be identified. We present an optimised ex vivo mycobacterial growth inhibition assay (MGIA) to assess the ability of host cells within the lung to inhibit mycobacterial growth, including Bacille Calmette–Guérin (BCG) and Mycobacterium tuberculosis (MTB) Erdman. Growth of BCG was reduced by 0.39, 0.96 and 0.73 log10 CFU following subcutaneous (s.c.) BCG, intranasal (i.n.) BCG, or BCG s.c. + mucosal boost, respectively, versus naïve mice. Comparatively, a 0.49 (s.c.), 0.60 (i.n.) and 0.81 (s.c. + mucosal boost) log10 reduction in MTB CFU was found. A BCG growth inhibitor, 2-thiophenecarboxylic acid hydrazide (TCH), was used to prevent quantification of residual BCG from i.n. immunisation and allow accurate MTB quantification. Using TCH, a further 0.58 log10 reduction in MTB CFU was revealed in the i.n. group. In combination with existing methods, the ex vivo lung MGIA may represent an important tool for analysis of vaccine efficacy and the immune mechanisms associated with vaccination in the organ primarily affected by MTB disease.

2-Thiophenecarboxylic acid hydrazide Derivatives: Synthesis and Anti-Tuberculosis Studies

One of the most frequent and widespread infectious diseases especially in developing countries is tuberculosis (TB). The number of TB drug resistant tend to increase, and there has been no new TB drug introduce since the 1960s. Six 2-Thiophenecarboxylic acid hydrazide derivatives were synthesized in 90-97% yields, and 2-thiophenecarbonylhydrazone-5, 7-dibromoisatin showed the highest activity in inhibiting M. tuberculosis H37Rv.

Intracellular application and logic gate behavior of a ‘turn off-on-off’ type probe for selective detection of Al3+ and F− ions in pure aqueous medium

Abstract A new Schiff base tcph, derived from 2-thiophene carboxylic acid hydrazide, has been synthesized and characterized by various spectroscopic techniques. The molecular structure of the compound has also been determined by X-ray crystallography. The tcph acts as a selective Al3+ and F− induced OFF-ON-OFF type of probe in aqueous media. The 1:1 binding stoichiometry between probe and Al3+ has been established from Job’s plot and further supported by ESI–MS studies. The limit of detection of Al3+ ions is determined by 3σ methods, which is found to be 1.35 × 10−9 M. The coordination environment for the tcph-Al3+ complex is delineated by NMR titration and DFT calculations. Detailed insights of probe–metal interaction mechanism have been studied by density functional theory (DFT) as well as time dependent–DFT calculations. MTT assay of the probe on live SiHa cells suggests no serious cytotoxicity in cells even at higher concentration. The probe tcph and its tcph-Al3+ complex have also been successfully applied to detect Al3+ and F− ions in living cells (SiHa cells), respectively.

Inhibition of copper corrosion by the formation of Schiff base self-assembled monolayers

Self-assembled monolayers (SAMs) of 4-((2-thiophenecarboxylic acid hydrazide) methylene) benzoic acid (HD2) (denoted as HD2-SAMs) were formed on copper surface. The SAMs were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. Polarization curve and weight loss methods indicated that the highest inhibition efficiency was 93.9% for CO2-saturated simulative oilfield water at a self-assembled time of 3h. Potential-time curve, electrochemical impedance tests showed that HD2-SAMs on copper surface exhibited excellent inhibition effect at 30°C. The adsorption behavior of HD2-SAMs on the copper surface followed the Langmuir adsorption isotherm, which was indicative of typically chemical adsorption. Quantum chemistry calculation showed that O and N atoms can interact with Cu atoms by coordination bonds which were the mainly active area of the adsorption of HD2 molecules.

Structural and spectroscopic investigation on a new potentially bioactive di-hydrazone containing thiophene heterocyclic rings

Hydrazones and several substituted hydrazones are associated with a broad spectrum of biological activities, as well as compounds containing the thiophene ring. In this context, a novel di-hydrazone derived from 2-thiophenecarboxylic acid hydrazide was synthesized and completely characterized by elemental analysis, XRD, FT-IR, Raman and UV–Vis spectroscopies, thermogravimetry, 1H NMR, 1H–1H COSY and 1H–1H ROESY. A preliminary in silico pharmacological evaluation was also performed in order to assess the performance of the new compound regarding some molecular properties relevant for a drug's pharmacokinetics in the human body.

Synthesis and Study of Antibacterial and Antifungal Activities of Novel 3-Alkyl-2,6-diarylpiperidin-4-one-2-thienoyl Hydrazone

In the present work a new series of 3-alkyl-2,6-diarylpiperidin-4-one-2-thienoyl hydrazones have synthesized by the reaction of 3-alkyl-2, 6-diarylpiperidin-4-one with 2-thiophenecarboxylic acid hydrazide and characterized by spectral (IR, 1 H NMR, 13 C NMR, HSQC, HMBC, NOESY and COSY) techniques. The hydrazones were screened for their in vitro antibacterial and antifungal activities against some selected micro organism. The results show that, compounds with halo-substituents at para position of the phenyl showed good antibacterial profile and antifungal against all tested organism.

Synthesis and biological activities of some novel aminomethyl derivatives of 4-substituted-5-(2-thienyl)-2,4-dihydro-3H-1,2,4-triazole-3-thiones

A novel series of compounds were synthesized by cyclic condensation reaction of substituted isothiocyanate (2a–c) with 2-thiophenecarboxylic acid hydrazide (1) in the presence of ethyl alcohol, to obtain intermediate thiosemicarbazides (3a–c), which were further treated with sodium hydroxide in the presence of ethanol to obtain triazole derivatives (4a–c). The latter were refluxed with substituted secondary amines and formaldehyde for 6–10 h to afford Mannich bases (5a–k). The synthesized compounds were characterized on the basis of their spectral (IR, 13C and 1H NMR) data and evaluated for biological activities. Some of the compounds were found to exhibit significant antimicrobial and antioxidant activity.

Corrosion Inhibition and Adsorption Behavior of 4-((2-Thiophenecarboxylic Acid Hydrazide)methylene)benzoic Acid) on Copper Surface in CO<sub>2</sub>-Saturated Oilfield Water

The inhibition effect and inhibition mechanism of a 4-((2-thiophenecarboxylic acid hydrazide)methylene)benzoic acid) (HD) against copper corrosion in CO2-saturated oilfield water was evaluated using electrochemical techniques and scanning electron microscopy. The experimental results shown that HD is a good corrosion inhibitor and the inhibition efficiency increased with the increase of HD concentration, and research indicate that adsorption behavior of the HD followed the langmuir’s adsorption isotherm and the adsorption mechanism is typical chemisorption.

Fast identification of mycobacteria in microtiter liquid culture

This research was to establish a method for fast identification of mycobacteria in microtiter liquid culture and to evaluate its clinical value. 2-thiophenecarboxylic acid hydrazide (TCH) and paranitrobenzoic acid (PNB) at different concentrations were added into liquid culture in 96-well plate. Different mycobacterium standard strains were incubated in liquid culture with PNB and TCH for 7 to 10 days. According to the growth assay for 15 mycobacterium strains and 30 mycobacterium tuberculosis strains, the best PNB and TCH concentration were determined. A total of 424 clinical mycobacterium isolates were identified by microtiter liquid culture at the best PNB and TCH concentration. The results of microtiter liquid culture were compared with those of PCR and DNA sequencing. The best concentration of PNB was 200 µg/ml in microtiter liquid culture. Compared with the results of PCR, the sensitivity and specificity for identification of mycobacterium tuberculosis complex in microtiter liquid culture were 97.8% (306/313) and 100.0% (107/107) respectively and those for non-tuberculosis mycobacteria in microtiter liquid culture were 100.0% (107/107) and 96.5% (306/317) respectively. The best concentration of TCH was 0.5 µg/ml. Compared with the results of PCR, the sensitivity of mycobacterium tuberculosis in microtiter liquid culture was 100.0% (305/305). The specificity remained under and more studies were needed. In microtiter liquid culture with PNB and TCH, mycobacteria can be identified in 7 to 10 days. The results were accurate and the process was simple without expensive equipments. This method meets clinical needs and can be used in all level hospitals in China.

Thermochemical and thermophysical study of 2-thiophenecarboxylic acid hydrazide and 2-furancarboxylic acid hydrazide

The standard ( p ∘ = 0.1 MPa) molar energies of combustion, Δ c U m ∘ , for the crystalline 2-thiophenecarboxylic acid hydrazide and 2-furancarboxylic acid hydrazide were determined, at the temperature of 298.15 K, by rotating bomb and static bomb combustion calorimetry, respectively. For these compounds, the standard molar enthalpies of sublimation, Δ cr g H m ∘ , at T = 298.15 K, were derived by the Clausius–Clapeyron equation, from the temperature dependence of the vapour pressures of these compounds, measured by the Knudsen effusion mass-loss technique. The results were as follows: - Δ c U m ∘ ( cr ) / ( kJ · mol - 1 ) - Δ f H m ∘ ( cr ) / ( kJ · mol - 1 ) Δ cr g H m ∘ / ( kJ · mol - 1 ) 2-Thiophenecarboxylic acid hydrazide 3359.4 ± 1.1 63.9 ± 1.3 113.3 ± 0.5 2-Furancarboxylic acid hydrazide 2620.8 ± 0.6 205.5 ± 0.9 99.0 ± 0.7 These values were used to derive the standard molar enthalpies of formation of the title compounds in their gaseous phases and the results are discussed in terms of energetic effects of the introduction of the –CONHNH 2 group in the thiophene and furan rings. Using estimated values for the heat capacity differences between the gas and the crystal phases of the studied compounds, the standard ( p ∘ = 0.1 MPa) molar enthalpies, entropies, and Gibbs energies of sublimation, at T = 298.15 K, were derived.

Effect of pyridoxal isonicotinoyl hydrazone and other hydrazones on iron release from macrophages, reticulocytes and hepatocytes

A model consisting of 59Fe-labelled macrophages was developed for screening potential iron-chelating drugs. Mouse peritoneal macrophages, induced by previous intraperitoneal injections of 3% thioglycollate, were labelled in vitro by their exposure to immune complexes of 59Fe-transferrin-antitransferrin antibody. Optimal conditions for macrophage labelling and subsequent 59Fe release were established. Sixty-two aromatic hydrazones, the majority of which had iron binding structures similar to pyridoxal isonicotinoyl hydrazone, were synthesized by condensation of aromatic aldehydes (pyridoxal, salicylaldehyde, 2-hydroxy-1-naphthylaldehyde and 2-furaldehyde) with various acid hydrazides perpared by systematic substitutions on the benzene ring. These compounds were examined for their potential to stimulate 59Fe release from 59Fe-labelled macrophages and also from reticulocytes and hepatocytes loaded with non-heme 59Fe. The majority of hydrazones derived from pyridoxal, salicylaldehyde and 2-hydroxy-1-naphthylaldehyde seemed to be equally effective in both the macrophage and reticulocyte testing systems. However, the pyridoxal hydrazones were much more active in hepatocytes than the other groups of hydrzaones. Several compounds proved to be very potent in mobilizing 59Fe. These included hydrazones derived from 2-hydroxyl-1-naphthylaldehyde and benzoic acid hydrazide, p-hydroxybenzoic acid hydrazide, 2-thiophenecarboxylic acid hydrazide, and also pyridoxal benzoyl hydrazone, pyridoxal m-fluorobenzyol hydrazone and pyridoxal 2-thiophenecarboxyl hydrazone.

In vitro antimicrobial susceptibility of a Mycobacterium sp. isolated from patients with Crohn's disease.

The in vitro susceptibility of three strains of an unclassified Mycobacterium sp., isolated from three patients with Crohn's disease, to 23 antimicrobial agents was determined by a modified broth dilution method with 7H9 broth containing oleic acid-albumin-dextrose-catalase, Tween 80, and mycobactin J. All three strains were susceptible to streptomycin, viomycin, rifampin, clofazimine, cefazolin, amikacin, and kanamycin and resistant to p-aminosalicylic acid, cycloserine, 2-thiophenecarboxylic acid hydrazide, trimethoprim, diaminodiphenylsulfone, sulfamethoxazole, sulfadimethoxine, polymyxin B, metronidazole, neomycin, and carbenicillin. Variable results between strains were encountered with ethambutol, ethionamide, capreomycin, amoxicillin, and cephalothin.