Thiazole Moiety Research Articles

Identification of the thiamin salvage enzyme thiazole kinase in Arabidopsis and maize

The breakdown of thiamin (vitamin B1) and its phosphates releases a thiazole moiety, 4-methyl-5-(2-hydroxyethyl)thiazole (THZ), that microorganisms and plants are able to salvage for re-use in thiamin synthesis. The salvage process starts with the ATP-dependent phosphorylation of THZ, which in bacteria is mediated by ThiM. The Arabidopsis and maize genomes encode homologs of ThiM (At3g24030 and GRMZM2G094558, respectively). Plasmid-driven expression of either plant homolog restored the ability of THZ to rescue Escherichia coli thiM deletant strains, showing that the plant proteins have ThiM activity in vivo. Enzymatic assays with purified recombinant proteins confirmed the presence of THZ kinase activity. Furthermore, ablating the Arabidopsis At3g24030 gene in a thiazole synthesis mutant severely impaired rescue by THZ. Collectively, these results show that ThiM homologs are the main source of THZ kinase activity in plants and are consequently crucial for thiamin salvage.

Spectroscopy and Photophysics of Bifunctional Proton Donor–Acceptor Indole Derivatives

We report spectroscopic and photophysical studies of a series of selected indole derivatives in solutions and under supersonic jet isolation conditions. All the compounds can assume two rotameric forms, syn and anti. The bifunctional molecules containing both the hydrogen bond donor (indole NH group) and acceptor centers (oxygen, nitrogen, or sulfur atoms) located in separate moieties covalently linked by a single bond are compared with the compound that does not have any acceptor center, 2-(1H-pyrrol-2'-yl)-1H-indole. The former compounds (containing furan, thiazole, or thiophene moieties) were anticipated to show solvent-dependent photophysics. Contrary to the expectations, all the compounds reveal very efficient fluorescence, independent of solvent polarity and hydrogen bond donor and acceptor abilities. Laser spectroscopic studies combined with supersonic jet techniques and quantum chemical computations have been performed in order to identify the rotameric forms and to gain insight into the changes in the molecular structure accompanying electronic excitation.

DBU-catalyzed condensation of metal free and metallophthalocyanines containing thiazole and azine moieties: Synthesis, characterization and electrochemical properties

Schiff base that contains carbothioamide moiety, substituted thiazole derivative, novel phthalonitrile compound and its corresponding metal free and metal phthalocyanines (Zn(II), Ni(II), Co(II) and Cu(II)) were synthesized and characterized for the first time. The solubility of these novel phthalocyanines were high in organic solvents and they did not aggregate in chloroform within the concentration range of 1.6 × 10−5–4 × 10−6 M. Electrochemical properties of the phthalocyanines have been examined by cyclic voltammetry, square wave voltammetry and in situ UV–vis spectroelectrochemistry on Pt in dimethylsulfoxide/tetrabutylammonium perchlorate. These measurements suggested that the compounds display subsequent ligand- and/or metal-based one-electron reduction and oxidation processes. Cobalt complex showed both metal-based and ring-based one-electron redox processes, while the other complexes displayed only ring-based one-electron couples. It was observed that the redox processes of metal free, Zn(II), Ni(II) and Cu(II) phthalocyanines are coupled by aggregation phenomenon, whereas those CoPc are not, probably due to the difference in their axial coordinating properties.

Pyridine-Substituted Desoxyritonavir Is a More Potent Inhibitor of Cytochrome P450 3A4 than Ritonavir

Utilization of the cytochrome P450 3A4 (CYP3A4) inhibitor ritonavir as a pharmacoenhancer for anti-HIV drugs revolutionized the treatment of HIV infection. However, owing to ritonavir-related complications, there is a need for development of new CYP3A4 inhibitors with improved pharmacochemical properties, which requires a full understanding of the CYP3A4 inactivation mechanisms and the unraveling of possible inhibitor binding modes. We investigated the mechanism of CYP3A4 interaction with three desoxyritonavir analogues, containing the heme-ligating imidazole, oxazole, or pyridine group instead of the thiazole moiety (compounds 1, 2, and 3, respectively). Our data show that compound 3 is superior to ritonavir in terms of binding affinity and inhibitory potency owing to greater flexibility and the ability to adopt a conformation that minimizes steric clashing and optimizes protein-ligand interactions. Additionally, Ser119 was identified as a key residue assisting binding of ritonavir-like inhibitors, which emphasizes the importance of polar interactions in the CYP3A4-ligand association.

Synthesis of New Isolated and Fused Tri- and Tetracyclic Pyridine Derivatives

A number of functionalized pyridine derivatives in which the pyridine ring is linked to triazole, thiadiazole, thiazole, and tetrazole moieties were synthesized by cyclization with carbon disulfide, phenylisothiocyanate, and sodium azide. Benzylation of the synthesized tetrazolylmethylpyridone derivative afforded the N(1)-benzylated product; its crystal structure is reported. The substituted fused tetracyclic pyridofuropyrimidine was synthesized by sequential reactions starting from the 2-pyridone derivative.

Novel Thiazolo[5,4‐d]thiazole‐Based Organic Dyes for Quasi‐Solid‐State Dye‐Sensitized Solar Cells

A series of novel metal-free organic dyes containing the thiazolo[5,4-d]thiazole moiety were designed and synthesized for quasi-solid-state dye-sensitized solar cells (DSSCs). Different alkoxy chains were introduced into the electron donor part of the dye molecules for comparison. The optical, electrochemical, and photovoltaic properties for all sensitizers were systematically investigated. It was found that the sensitizers with the different alkoxy groups have similar photophysical and electrochemical properties, such as absorbance and energy levels, owing to their close chemical structures. However, the quasi-solid-state DSSCs based on the resulting sensitizers exhibit different performance parameters. The quasi-solid-state DSSC based on sensitizer FNE74 with two octyloxy chains possessed the highest solar energy conversion efficiency of 5.10 % under standard AM 1.5G sunlight illumination without the use of coadsorbant agents.

Synthesis, characterization and antimicrobial activity of certain novel aryl hydrazone pyrazoline-5-ones containing thiazole moiety.

The aim of this article is to synthesize, characterize and evaluate the antimicrobial activity of certain novel 3-methyl-5-oxo-4-(phenyl hydrazono)-4,5-dihydro-pyrazol-1-yl]-acetic acid N|-(4-substituted thiazol-2-yl)-hydrazides. The synthesized compounds were characterized by elemental analysis and IR, NMR and mass spectral data. The antimicrobial activity of novel compounds was evaluated by broth dilution method. XVe, XVf and XVg have shown better antibacterial activity than other compounds of the series. XVa, XVc, XVd and XVe have shown better antifungal activity than the other compounds of the series. All compounds were found to exhibit fair degree of antimicrobial activity.

Synthesis and antimicrobial evaluation of certain novel thiazoles.

This article makes an attempt to synthesize certain compounds containing thiazole and imidazole moieties and screen for the antimicrobial properties. The novel compounds synthesized were characterized by elemental analysis, IR and (1)HNMR spectral data. The antimicrobial activity of novel compounds was evaluated by cup plate method. The compound p-t showed more antibacterial activity than that of the standard. p-hp and p-as showed considerable antibacterial activity. p-t demonstrated higher antifungal activity than that of the standard while p-hp and p-as showed considerable antifungal activity. The antimicrobial activity studies were conducted on certain selected bacteria and fungi. In each case antimicrobial activity of the compounds was compared with that of standards. p-t, p-hp, p-np, p-cp, p-ts and p-as showed considerable antimicrobial activity.

Asymmetric synthesis of enantiomerically enriched (S)-α-aminopropionic acids containing heterocyclic side chains

The conjugate addition of S-, N- and O-heterocyclic nucleophiles to the CC bond of dehydroalanine, bonded as a Schiff’s base to the chiral auxiliary (S)-2-[N-(N′-benzylprolyl)amino]benzophenone in the coordination sphere of NiII, resulted in the asymmetric synthesis of novel (S)-α-aminopropionic acids containing a heterocyclic side chain, including imidazole, triazole, thiodiazole, thiazole and oxazole moieties (de 20–92%). After purification and cleavage of the metal complexes, the heterocyclic amino acids were isolated with high enantiomeric purity (ee >97%).

Discovery of a novel broad-spectrum antifungal agent derived from albaconazole.

Synthesis of a strict structural analogue of albaconazole in which the quinazolinone ring is fused by a thiazole moiety led to the discovery of a new triazole with broad-spectrum antifungal activity. Compound I exhibited high in vitro activity against pathogenic Candida species and filamentous fungi and showed preliminary in vivo antifungal efficacy in a mice model of systemic candidiasis.

QSAR studies of novel potent benzamide derivatives as glucokinase activators

Two-dimensional QSAR studies of benzamide derivatives as allosteric glucokinase activators agents were performed on a series of 47 compounds. The structures were sketched using chemsketch 12.5 versions then subjected to energy minimization, and the lowest energy structures were used to calculate the physiochemical properties using Vlife MDS 3.5 version for molecular modeling study. The best model so generated from QSAR studies showed regression values having n = 32, r 2 = 0.8669, q 2 = 0.6423, pred_r 2 = 0.6408, r 2se = 0.3247, q 2se = 0.3650, pred_r 2se = 0.3635 (standard errors), and descriptor so generated were chiV4pathcluster, SsNH2E-index, and SdssCE-index. The study revealed that increase in the activity was due to bulky substitution on benzamide and thiazole moiety. Moreover, –NH2 group plays a significant role in activating glucokinase enzyme by binding specifically on the position of benzamide. This binding will lead to formation of hydrogen bond between tyrosine present in enzyme and amino group of concerned benzamide moiety. This study can help in rational drug design and synthesis of new allosteric glucokinase activator with predetermined affinity.

Examining strategies to facilitate vitamin B1 biofortification of plants by genetic engineering

Thiamin (vitamin B1) is made by plants and microorganisms but is an essential micronutrient in the human diet. All organisms require it as a cofactor in its form as thiamin pyrophosphate (TPP) for the activity of key enzymes of central metabolism. In humans, deficiency is widespread particularly in populations where polished rice is a major component of the diet. Considerable progress has been made on the elucidation of the biosynthesis pathway within the last few years enabling concrete strategies for biofortification purposes to be devised, with a particular focus here on genetic engineering. Furthermore, the vitamin has been shown to play a role in both abiotic and biotic stress responses. The precursors for de novo biosynthesis of thiamin differ between microorganisms and plants. Bacteria use intermediates derived from purine and isoprenoid biosynthesis, whereas the pathway in yeast involves the use of compounds from the vitamin B3 and B6 groups. Plants on the other hand use a combination of the bacterial and yeast pathways and there is subcellular partitioning of the biosynthesis steps. Specifically, thiamin biosynthesis occurs in the chloroplast of plants through the separate formation of the pyrimidine and thiazole moieties, which are then coupled to form thiamin monophosphate (TMP). Phosphorylation of thiamin to form TPP occurs in the cytosol. Therefore, thiamin (or TMP) must be exported from the chloroplast to the cytosol for the latter step to be executed. The regulation of biosynthesis is mediated through riboswitches, where binding of the product TPP to the pre-mRNA of a biosynthetic gene modulates expression. Here we examine and hypothesize on genetic engineering approaches attempting to increase the thiamin content employing knowledge gained with the model plant Arabidopsis thaliana. We will discuss the regulatory steps that need to be taken into consideration and can be used a prerequisite for devising such strategies in crop plants.

Thiazolo[5,4-d]thiazoles – promising building blocks in the synthesis of semiconductors for plastic electronics

The thiazolo[5,4-d]thiazole fused (bi)heterocycle is an electron deficient system with high oxidative stability and a rigid planar structure, enabling efficient intermolecular π–π overlap. The parent thiazolo[5,4-d]thiazole moiety hence already possesses some appealing features towards applications in organic electronics. Moreover, aryl-functionalized thiazolo[5,4-d]thiazole derivatives – expanding the conjugated backbone of the semiconducting material – are easily prepared. Surprisingly, interest in thiazolo[5,4-d]thiazole-based materials has been rather low, until quite recently, when the high potential of these molecules was widely recognized, notably in the field of organic photovoltaics. Despite the almost exponential growth of activity, the synthetic chemistry behind these molecules has only been explored to a minor extent and there is plenty of room for improvement and broadening of the material scope. In this review, an overview of the currently available synthetic methods and the range of materials prepared to date, together with their basic material properties and main applications, is provided, with the aim to facilitate and stimulate further progress in thiazolo[5,4-d]thiazole-based materials science.

Synthesis and Herbicidal Activity of Amide Derivatives Containing Thiazole Moiety

Synthesis and Herbicidal Activity of Amide Derivatives Containing Thiazole Moiety

Synthesis and Antimicrobial Activity of some Amide Derivatives Bearing Thiazole, Benzhydryl and Piperidine Moieties

Synthesis and Antimicrobial Activity of some Amide Derivatives Bearing Thiazole, Benzhydryl and Piperidine Moieties

Synthesis of Novel 2,3-Disubstituted 1,4-Naphthoquinone Derivatives Containing Indole, Quinoline, Thiazole and Imidazole Moieties

;) The pr esent work descr ibes one-pot multicomponent synthesis in w hich Mic hael addition-elimination reactions of the precursors 2-chloro-3-(2-arylhydrazinyl)naphthalene-1,4-dione, 2-amino-4,9-dioxo-4,9-dihydro-1H-benzo[f]indole-3-carbonitrile and 2-amino-4aryl-5,10-dioxo-5,10-dihydrobenzo[g]quinoline-3-carbonitrile with carbon disulphide, followed b y intr amolecular cyclization in the presence of p yridine or sulphur ic acid or h ydrazine have led to f ormation of the corresponding 3-arylamino-2-thioxo-2,3-dihydronaphtho[2,3-d]thiazole-4,9-dione, 2-thioxo-2H-benzo[f]thiazolo[4,5-b]indole-5-10(3H,4H)-dione, 2-mercapto benzo[f]thiazolo[4,5b]indole-5-10(1H,4H)-dione, 11-aryl-2-thioxo-2,3-dihydrotobenzo[g]thiazolo [4,5-b]quinoline-5,10-dione and 1-amino-11-aryl-2mercapto-1H-benzo[g]imidazo[4,5-b] quinoline-5,10-dione. The synthesized compounds have been identified and their structures are in confirmation with various spectroscopic techniques including IR,

Planar triazinium cations from vanadyl-mediated ring cyclizations: the thiazole species for efficient nuclear staining and photocytotoxicity

Planar triazinium cationic species from vanadyl-assisted cyclization of 1-(2-thiazolylazo)-2-naphthol (H-TAN, 1), 1-(2-pyridylazo)-2-naphthol (H-PAN, 2), 2-(2'-thiazolylazo)-p-cresol (H-TAC, 3) and 6-(2'-thiazolylazo)-resorcinol (H-TAR, 5) were prepared and characterized. A dioxovanadium(V) species [VO(2)(TAR)] (4) was also isolated. Compounds 1, 2 and 4 were structurally characterized. Both 1 and 2 have planar structures. Complex 4 has V(V)O(3)N(2) coordination geometry. The cyclised triazinium compound forms a radical species within -0.06 to -0.29 V vs. SCE in DMF-0.1 M tetrabutylammonium perchlorate with a second response due to formation of an anionic species. A confocal microscopic study showed higher nuclear uptake for 1 having a fused thiazole moiety than 2 with a fused pyridine ring. The compounds showed a partial intercalative mode of binding to calf thymus DNA. Compound 1 showed plasmid DNA photo-cleavage activity under argon and photocytotoxicity in HeLa and MCF-7 cells with IC(50) values of 15.1 and 3.4 μM respectively in visible light of 400-700 nm, while being essentially non-toxic in the dark with IC(50) values of 90.4 and 21.9 μM. A TDDFT study was done to rationalize the experimental data.

Facile Synthesis, Characterization, and Fluorescence Studies of Novel Porphyrin Appended Thiazoles

A facile and high yielding synthesis of porphyrin appended thiazoles 5 from the reaction of 5-(4-thiocarboxamidophenyl)-10,15,20-triphenylporphyrin with α-bromo ketones has been described. The fluorescence studies of synthesized porphyrin appended thiazoles 5 in chloroform indicate that porphyrin π system is not greatly perturbed by substitution of a thiazole moiety at meso-phenyl ring even in the excited state.

Synthesis and Antimicrobial Activity of some Amide Derivatives Bearing Thiazole, Benzhydryl and Piperidine Moieties

Synthesis and Antimicrobial Activity of some Amide Derivatives Bearing Thiazole, Benzhydryl and Piperidine Moieties

Synthesis and Antimicrobial Activity of some Amide Derivatives Bearing Thiazole, Benzhydryl and Piperidine Moieties

In the present study, N-(benzhydryl/thiazol-2-yl)-2-(piperidin-1-yl)acetamide derivatives were obtained by the reaction of 2-chloro-N-(benzhydryl/thiazole-2-yl)acetamides with piperidine derivatives. The chemical structures of the compounds were elucidated by IR, 1H-NMR, and mass spectral data and elemental analyses. These compounds were investigated for their antimicrobial effects. The microbiological results revealed that the compounds were more effective against C. albicans (ATCC-22019) than bacteria. Among all compounds (1-9), compound 3 bearing benzhydryl and 4- methylpiperidin-1-yl moieties was found to be the most effective compound against C. albicans. Compound 3 exhibited antibacterial activity against P. aeruginosa with a MIC value of 62.5 μg/mL, whereas streptomycin showed antibacterial activity against P. aeruginosa with a MIC value of 125 μg/mL. Furthermore, compound 3 exhibited the same level of antibacterial activity against S. aureus when compared with streptomycin. Other derivatives did not show significant activity against the tested bacteria. Keywords: Amide, Thiazole, Benzhydryl, Piperidine, Antimicrobial activity, Cephalosporins, N-Alkylamides, Listeria monocytogenes, Pseudomonas aeruginosa, Mueller–Hinton