Synthesis and biological activities of thio-triazole derivatives as novel potential antibacterial and antifungal agents

A series of novel thio-triazole derivatives including thiols, thioethers and thiones as well as some corresponding triazolium compounds were conveniently and efficiently synthesized from commercially available halobenzyl halides and thiosemicarbazide. All the new compounds were characterized by 1 H NMR, 13 C NMR, FTIR, MS and HRMS spectra. Their antibacterial and antifungal activities in vitro were evaluated against four Gram-positive bacteria, four Gram-negative bacteria and two fungi by two-fold serial dilution technique. The preliminary bioassay indicated that some prepared triazoles exhibited effective antibacterial and antifungal activities. Especially, 3,4-dichlorobenzyl triazolethione and its triazolium derivatives displayed the most potent activities against all the tested strains.     

Synthesis and properties of furanyl 1,3-dioxolanes. 2. Synthesis of new derivatives of furanyl 1,3-dioxolanes

New derivatives of furnayl 1,3-dioxolanes containing amino, ammonium, alkoxy, and vinyl groups in the dioxolane fragment were synthesized.For Communication 1, see [1].Translated from Khimiya Geterotisiklicheskikh Soedinenii, No. 3, pp. 325–328, March, 1993.     

Synthesis of 1,3-dithiolane-containing nitromethene compounds and their biological activity as insecticides

1,3-Dithiolane-containing nitromethylene derivatives, as candidates for screening as neonicotinoid insecticides, were synthesized by reaction of compound (4) with 1,2-ethanedithiol. Compounds 7a–g were obtained via Mannich reaction of (E)-1-((1,3-dithiolan-2-yl)methyl)-2-(nitromethylene)imidazolidine (6), primary amines and formaldehyde. The synthesized compounds were identified by ¹H NMR, IR spectroscopy and elemental analysis. Preliminary bioassays indicated that most of the compounds had moderate insecticidal activity against Aphis craccivora. The relationship between molecular structure and biological activity is discussed.     

Synthesis and biological evaluation of new pyrrolopyrazinone compounds as potential antitumor agents

A series of pyrrolo[1,2-a]pyrazinone compounds(5a-9f) were synthesized,and their cytotoxic activity against SKOV-3,A549.HeLa cells in vitro were evaluated by the MTT method.Some of the compounds showed potential antitumor activity against three tumor cell lines.Among them,compounds 9c and 9d showed the most potent cytotoxic activity.The preliminary mechanism of action was discussed.     

Synthesis and biological evaluation of dihydrotriazine derivatives as potential antibacterial agents

A series of 1,4-dihydro-1,3,5-triazine derivatives were designed and synthesized and their antibacterial and antifungal activities were evaluated. Most of the synthesized compounds showed potent inhibition of several Gram-positive bacterial strains(including multidrug-resistant clinical isolates) and Gramnegative bacterial strains, with minimum inhibitory concentrations(MICs) in the range of 2.1–181.2 mmol/L. Compounds 7a and 7c presented the most potent inhibitory activities against Grampositive bacteria(e.g., Staphylococcus aureus 4220), Gram-negative bacteria(e.g., Escherichia coli 1924),and the fungus Candida albicans 7535, with MICs of 2.1 or 4.1 mmol/L. Especially, compound 7a was the most potent, with an MIC of 2.1 mmol/L against four multidrug-resistant, Gram-positive bacterial strains.The cytotoxic activity of the compound 7a, 7c and 7f was assessed in HepG2 cells, and the results suggest that 1,4-dihydro-1,3,5-triazine derivatives bearing a 6-benzyloxynaphthalen moiety are interesting scaffolds for the development of novel antibacterial agents.     

Synthesis and properties of new halogen-substituted 2-pentafluorophenyl-2-trifluoromethyl-1,3-dioxolanes

2-Pentafluorophenyl-2-trifluoromethyl-1,3-dioxolane was prepared by cyclization of octafluoroacetophenone with 2-chloroethanol under the conditions of base catalysis. Successive chlorination of the product yielded the corresponding 4,4,5,5-tetrachloro derivative. Fluorination of the latter in the SbF₃/SbCl₅ system yields 4,5-dichloro-4,5-difluoro-2-pentafluorophenyl-2-trifluoromethyl-1,3-dioxolane.     

Synthesis and biological evaluation of 1,3,4-oxadiazole fused pyridine derivatives as antibacterial and antifungal agents

Russian Journal of General Chemistry - A series of novel 1,3,4-oxadiazole fused pyridine derivatives were synthesized 11a–11f and their structures confirmed by IR, 1H NMR and Mass spectral...     

Synthesis,complexation and antifungal,antibacterial activity studies of a new macrocyclic schiff base

A new macrocyclic ligand, L was synthesized using the high dilution condition with condensation of triethylene glycol diamine and terephtalaldehyde in ethanol. The obtained product, L was identified by FT‐IR, ¹H‐NMR, ¹³C‐NMR and Mass spectroscopy. The extraction equilibrium constants were estimated using dichloromethane/water membranes transfer with ICP‐AES and AES spectroscopy. Biological studies of this compound was determinated with disc diffusion method. The biological activity results showed that the synthesized ligand L has high activity against the studied microorganisms and high complexation ability against the Fe²⁺ cation.     

Synthesis and spectroscopic characterization of new tetradentate Schiff base and its coordination compounds of NOON donor atoms and their antibacterial and antifungal activity

New Schiff base (H₂L) ligand is prepared via condensation of o-phthaldehyde and 2-aminobenzoic acid in 1:2 ratio. Metal complexes are prepared and characterized using elemental analyses, IR, solid reflectance, magnetic moment, molar conductance, ¹H NMR, ESR and thermal analysis (TGA). From the elemental analyses data, the complexes were proposed to have the general formulae [MCl(L)(H₂O)]·2H₂O (where M = Cr(III) and Fe(III)); [M(L)]·yH₂O (where M = Mn(II), Ni(II), Cu(II) and Zn(II), y = 1–2) and [M(L)(H₂O)_n]·yH₂O (where M = Co(II) (n = y = 2), Co(II) (n = y = 1), Ni(II) (n = 2, y = 1). The molar conductance data reveal that all the metal chelates were non-electrolytes. IR spectra show that H₂L is coordinated to the metal ions in a bi-negative tetradentate manner with NOON donor sites of the azomethine-N and carboxylate-O. The ¹H NMR spectral data indicate that the two carboxylate protons are also displaced during complexation. From the magnetic and solid reflectance spectra, it was found that the geometrical structure of these complexes are octahedral (Cr(III), Fe(III), Co(II) and Ni(II)), square planar (Cu(II)), trigonal bipyramidal (Co(II)) and tetrahedral (Mn(II), Ni(II) and Zn(II)). The thermal behaviour of these chelates showed that the hydrated complexes losses water molecules of hydration in the first step followed immediately by decomposition of the ligand molecule in the subsequent steps. The biological activity data show that the metal complexes to be more potent/antibacterial than the parent Shciff base ligand against one or more bacterial species.     

Synthesis,anticorrosion, antibacterial,and antifungal activity of new amphiphilic compounds possessing quinazolin-4(3H)-one scaffold

Russian Chemical Bulletin - For the first time, quinazolin-4(3H)-one-based cationic surfactants were prepared and fully characterized by IR and NMR spectroscopic techniques and elemental analysis....     

Synthesis of 1,3-dioxolanes from acetylenic 1,2,5-triols

The reaction of acetylenic 1,2,5-triols with vinyl butyl ether in the presence of catalytic amounts of hydrochloric acid leads to the formation of 4-(3-hydroxy-1-alkynyl)-1,3-dioxolanes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1334–1335, October, 1988.     

Synthesis and biological effects of new derivatives of benzotriazole as antimicrobial and antifungal agents

Derivatives of 2‐aminothiophene‐3‐carbonitrile, 2‐thioxopyridine‐3‐carbonitrile, 1,8‐naphthyridine‐2‐one, thieno[2,3‐b]pyridine‐5‐carbonitrile and thieno[2,3‐d]pyrimidine incorporating with a 1H‐benzo‐triazole moiety or 1,3,4‐thiadiazole derivatives incorporating with a benzotriazol‐1‐ylmethyl group have been synthesized and tested for antimicrobial and antifungal activities. The structures of the newly synthesized compounds have been established on the basis of their analytical and spectral data.     

Synthesis of hydrazone derivatives of benzofuran and their antibacterial and antifungal activity

A series of benzofuran hydrazones 6a–6n were synthesized from benzofuran aldehyde and substituted aromatic hydrazides 5a–5n. Structures of all compounds were confimed by IR, ¹H and ¹³C NMR, and Mass spectral data. These compounds were evaluated for their antibacterial activity against gram-negative bacteria (Escherichia coli, –ve), gram-positive bacteria (Bacillus Subtillis, +ve), and antifungal activity against Candida albicans. All compounds demonstrated considerable activity against bacteria and fungi.     

Synthesis of cis-5-aryl-4-aroyl-1,3-dioxolanes

The reaction of trans-3-aryl-2-aroyloxiranes containing electron-acceptor substituents in the aryl group with acetone under acid-catalysis conditions gives the corresponding cis-1,3-dioxolanes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1315–1317, October, 1984.     

4-amino-2-phenylindole-based compounds with potential antibacterial activity

Primary condensation of 4-amino-2-phenylindole with ethyl acetoacetate and 4,4,4-trifluoroacetoacetate resulted in corresponding amides, which under acidic conditions were converted to pyrrolo[2,3-h]quinolones. Antibacterial activity of the amide obtained from aminoindole and ethyl 4,4,4-trifluoroacetylacetate was detected.     

Peptoids as source of compounds eliciting antibacterial activity

N-Alkylglycine oligomers (peptoids) constitute a family of non-natural peptidomimetics attractive for the early drug discovery process because of their physicochemical features, easy of adaptation to combinatorial chemistry approaches and their proteolytic stability. Consequently, peptoid libraries have found application for discovering hits against a wide diversity of pharmaceutical targets, among which different examples of antibacterials are found. In the present work, research efforts addressed towards the identification of peptoids as antibacterial agents are discussed.