Antibacterial and Cytotoxic Effects of Cyclodextrin-Triazole-Titanium Based Nanocomposite

Abstract In this paper, the antibacterial activity of triazole functionalized cyclodextrin (CD.Click) and cyclodextrin-triazole-titanium based nanocomposite (CD.COM) was evaluated. The results indicated that CD.Click and CD.COM perform a wide range of antibacterial activity against both gram positive (Staphylococcus aureus and Bacillus subtilis) and gram negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. The cytotoxic effect of CD.COM was investigated in vitro on cancerous cell lines (cervical cancer, breast carcinoma and sarcoma osteogenic) and fibroblast cells by MTT assay. The cell viability evaluation confirmed that the growth of cancerous cells is inhibited in a dose and time dependent way without any significant effect on the normal fibroblast cells.

1, 3, 4-Thiadiazole and 1, 2, 4-triazole-3(4 H )-thione bearing salicylate moiety: synthesis and evaluation as anti- Candida albicans

Abstract Dramatically increased occurrence of both superficial and invasive fungal infections has been observed. Candida albicans appear to be the main etiological agent of invasive fungal infections. The anti-C. albicans activity of thiosemicarbazide, 1,3,4-Thiadiazole, and 1,2,4-triazole-3(4H)-thione compounds (compounds 3-23) were investigated. The MIC values of thiadiazole and triazole derivatives 10-23 were in the range of 0.08-0.17 µmol mL-1, while that of fluconazole was 0.052 µmol mL-1. Compound 11 (5-(2-(4-chlorobenzyloxy)phenyl)-N-allyl-1,3,4-thiadiazol-2-amine) and compound 18 (5-(2-(4-chlorobenzyloxy)phenyl)-4-allyl-2H-1,2,4-triazole-3(4H)-thione) were found to be the most active compounds, with MIC values of 0.08 µmol mL-1. The newly synthesized thiadiazole and triazole compounds (compounds 10-23) showed promising anti-Candida activity. The allyl substituent-bearing compounds 11 and 18 exhibited significant anti-Candida albicans activity and showed a binding mode as well as the fluconazole x-ray structure.

Synthesis of new 1,2,4-Triazole derivatives of nalidixic acid as potential antibacterial and antifungal agents

Triazole and triazole fused heterocyclic ring systems possess diverse applications in the fields of medicine, agriculture and industry. A new series of nalidixic acid derivatives having 1,2,4-triazole moiety at position 3 were synthesised to achieve enhanced biological activity and wide spectrum of activity. Nalidixic acid was first converted into its methyl ester which upon hydrazinolysis afforded nalidixic acid hydrazide. Condensation of the hydrazide with CS[2]/KOH furnished the potassium dithiocarbazate salt, which cyclized to the 3-[4-amino-5-thioxo-4,5-dihydro-1H-l,2,4-triazol-3-yl]-1-ethyl-7-methyl-1H-[1,8] naphthyridin-4-one, [4], on refluxing with hydrazine hydrate. Condensation of the key intermediate 4 with aryl aldehydes afforded Schiffs bases 5a-f, while its reaction with alkyl or aralkyl halides gave compounds 6a-e. Furthermore, compounds 5a,e were reacted with benzyl chloride to afford 7a,b. The chemical structure of the target compounds was confirmed by IR, [1]H-NMR, FAB-MS, EI-MS spectra and elemental analyses. The title compounds and the starting Nalidixic acid; were tested for their in-vitro antibacterial and antifungal activities. Most of the tested compounds showed comparable antibacterial activity with those of Nalidixic acid and higher activity than ampicillin. The tested compounds and Nalidixic acid showed non or moderate antifungal activity in comparison to clotrimazole as a reference drug

Synthesis of some thiazolidinone and triazole dderivatives of expected antimicrobial activity

New derivatives of semicarbazide [5] and thiosemicarbazide [6] had been synthesized together with new substituted alkyl and aryl 1, 2, 4-triazoles [7] and thiazolidinone [8] obtained by cyclizing the appropriate thiosemicarbazide [6]. Screening for antibacterial and antifungal activities using preliminary scan by the agar plate inhibition zone method, followed by MIC versus ampicillin and clotrimazole revealed high activity for compounds [5-c] and [7-a]. The partition coefficient of the most and least biologically active compounds was determined and the results were reported

Synthesis and antibacterial activity of some Schiff bases and 4-thiazolidinones.

Some new schiff bases (1a-d) 4-thiazolidinones (2a-d) have been synthesised and tested for their antibacterial activity. The structures of these compounds have been established on the basis of elemental analysis and spectral data (IR and H1 NMR).

Hydrazidoy halides in heterocyclic synthesis: Synthesis of several new polyfunctional pyrazole and 1,2,4-Triazole derivatives via dipolar cycloduction reactions on the corresponding nitrile imines

The nitrile imine generated by the action of triethylamine on 2-bromo-1-benzofurylglyoxal-2-[3 phenylpyrazol 5-yl]-hydrazone reacted with some Schiff bases, -nitrostyrenes and thiocarboxamidocinnamonitrile derivatives via dipolar cycloaddition reactions to yield several new polyfunctional pyrazole and 1,2,4-triazole derivatives. Structures were confirmed by elemental analysis and spectral data studies

Studies on dehydro-l-ascorbic acid 2-arylhydrazones: conversion into substituted triazoles and pyrazolinediones

The 2-p-chlorophenylhydrazone of dehydro-L-ascorbic acid was reacted with hydroxyamine giving the 3-oxime. Dehydrative cyclization of the latter gave the triazole derivative. The lactone ring cleaved upon treatment with hydrazine, methylamine or dimethylamine giving the corresponding triazole carboxamide derivative. Periodate oxidation of the triazole carboxamide gave the 3-formyltriazole which upon reduction gave the corresponding alcohol, characterized as its monoacetate. The 2-hydrazone was condensed with arylhydrazine giving the mixed bis- hydrazones, which underwent rearrangement to the pyrazolinediones and gave the bicyclic 3,6-anhydro derivatives upon treatment with cupric chloride

Studies on dehydaro-d-erythro-and l-threo-ascorbic acid 2-arylhydrazone-3-oximes and mixed bishydrazones: conversion into substituted triazoles and pyrazolinediones

Reaction of p-nitrophenyltriazole of dehydro-D-erythro-ascorbic acid [I] with hydrazine hydrate in MeOH yielded the corresponding triazole hydrazide [II] which gave the triacetyl derivative [III]. Periodate oxidation of [II] gave the 3-formyltriazole derivative [IV] which formed a triacetyl derivative [VI]. The 3-formyl derivative [IV] was condensed with hydrazine hydrate and O-phenylenediamine to give compounds [VII] and [VIII], respectively. Treatment of [I] with ammonium hydroxide solution and MeOH gave the triazole carboxamide [IX] which produced two different acetyl derivatives [X] and [XI]. The p-nitrophenylhydrazone zone of dehydro-D-erythro-[XII] and dehydro-L- threo-ascorbic acid [XIII], reacted with phenylhydrazine to give the mixed bisarylhydrazones [XIV] and [XV], respectively, which formed the diacetyl derivatives [XVI] and [XVII]. Compound [XIV] underwent rearrangement to the corresponding pyrazole derivative [XVIII] which gave the acetyl product [XIX]. Periodate oxidation of [XVIII] gave the 3-formylpyrazole [XX] which yielded different condensation products [XXI]-[XXV]. Cupric chloride oxidation of [XV] gave the 3,6-anhydro derivative [XXVI] which characterized as its monoacetyl derivative [XXVII]