5-( [aryl or aryloxy (or thio)]methyl)-3-(1H-imidazol-1-ylmethyl)-3- (2-thienyl)-2-methylisoxazolidine derivatives as novel antifungal agents

The in vitro antifungal activity of a novel series of cis- and trans-5-([aryl or aryloxy (or thio)]methyl)-3-(1H-imidazol-1-ylmethyl)-3- (2-thienyl)-2-methylisoxazolidines (13-24) was evaluated and compared with ketoconazole. The title series of compounds was prepared via a 1,3-dipolar cycloaddition reaction of 1-(2-thienyl)-2-(1H-imidazol-1-yl)-N-methylethanimine N-oxides with appropriate styrenes, allyl phenyl ethers, or allyl phenyl thioether precursors. The resulting products were mixtures of the corresponding cis- and trans-diastereomers which were readily separated by flash chromatography on neutral silica gel. The majority of compounds 13-24, when tested in solid agar cultures, exhibited moderate to potent activity against Trichophyton rubrum, Aspergillus fumigatus, and Candida albicans at concentrations ranging between less than or equal to 2.0 and 70.0 micrograms/mL.     

Antifungal activity of novel 5-carbonyl derivatives of 3-phenyl-3-(1H-imidazol-1-ylmethyl)-2-methylisoxazolidines

The synthesis and antifungal activity of a series of novel 5-carbonyl derivatives of 3-phenyl-3-(1H-imidazol-1-ylmethyl)-2-methylisoxazolidines (4) are discussed. The preparation of the title compounds involved a 1,3-dipolar cycloaddition reaction of alpha-substituted ketonitrones with either acrylic esters, acrylamide or methyl vinyl ketone to furnish cis/trans-diastereomeric mixtures of the desired 5-carbonyl isoxazolidines 4. The anifungal activity was evaluated in vitro in solid agar cultures. Some of the compounds tested exerted moderate to potent activity against a wide variety of dermatophytes and yeast and systemic fungi.     

Studies on antifungal agents. 23. Novel substituted 3,5-diphenyl-3-(1H-imidazol-1-ylmethyl)- 2-alkylisoxazolidine derivatives

The synthesis and antifungal activity of a novel series of substituted 3,5-diphenyl-3-(1H-imidazol-1-ylmethyl)-2-alkylisoxazolidine derivatives (15-30) are described. The synthesis of the title compounds was accomplished via a 1,3-dipolar cycloaddition reaction of alpha-substituted ketonitrones with appropriate styrene precursors. The compounds when tested in vitro in solid agar cultures exerted a very potent antifungal activity against a wide variety of yeast and systemic mycoses and dermatophytes, especially Trichophyton and Microsporum sp., Epidermophyton floccosum and Candida stellatoidea. The in vitro activity against Aspergillus fumigatus and Candida albicans was moderate to potent. Overall, the two bis(4-chlorophenyl) analogues 18 and 19 were the most potent in vitro compounds, showing MIC values ranging between 0.2 and 7.0 microgram/mL, as compared to 0.2-20.0 micrograms/mL for ketoconazole, which was used as the positive standard in all assays. When tested in vivo in the rat vaginal candidiasis model, derivative 18, although showing significant antifungal activity when compared to controls, was less effective than ketoconazole. The title 3,5-substituted isoxazolidine compounds represent a novel class of potent antifungal agents.     

Syntheses and antifungal activities of 1-[4-phenyl-2-(phenylthio or acyloxy)-n-butyl]-1H-imidazole derivatives]

The title compounds (4b, d-f, h-j) were prepared from 1-[4-(p-substituted phenyl)-2-chloro-n-butyl]-1H-imidazoles and the corresponding thiophenols or mercaptopyridines. Acyloxy compounds (5a-e) were prepared from alcohol (2b) and the corresponding acyl chlorides. In the antifungal activity test, p-tolyl compounds (4e, f) showed as good activity as butoconazole (4c).     

Novel 5-substituted 3-(2-naphthalenyl)-3-(1H-imidazol-l-ylmethy)-2-methylisoxazolidine derivatives

The synthesis and antifungal activity of a series of novel 5-substituted 3-(2-naphthalenyl)-3-(1H-imidazol-1-ylmethyl)-2- methylisoxazolidine derivatives are described. When tested in vitro in solid agar assays, some of the compounds demonstrated moderate to potent activity against Trichophyton rubrum and Candida albicans.     

Cardiotonic agents. 3. Synthesis and biological activity of novel 6-(substituted 1H-imidazol-4(5)-yl)-3(2H)-pyridazinones

Several 6-(substituted 1H-imidazol-4(5)-yl)-3(2H)-pyridazinones were synthesized and evaluated for positive inotropic activity. The 1H-imidazol-4-yl regioisomers 4,5-dihydro-6-(1-methyl-2-phenyl-1H-imidazol-4-yl)-3(2H)-pyridazinone (25a) and 6-(1-methyl-2-phenyl-1H-imidazol-4-yl)-3(2H)-pyridazinone (28a) were potent positive inotropic agents. By contrast, the corresponding 1H-imidazol-5-yl regioisomers 25b and 28b were only weak positive inotropic agents. Compounds 25a and 28a were also potent inhibitors of cardiac phosphodiesterase fraction III.     

Synthesis and antifungal properties of N-[(1,1'-biphenyl)-4-ylmethyl]-1H-imidazol-1-amine derivatives

In the course of a study on 1H-imidazol-1-amine derivatives as antifungal agents, we found that N-[(1,1'-biphenyl)-4-ylmethyl]-N-[(2,4-dichlorophenyl)methyl]-1H-imidazol-1-amine (1a) exhibited promising activities. In order to explore more in detail the structure-activity relationship of this new class of antifungal agents, we report now the synthesis and the biological activity of new analogues (1b-k) of compound 1a. The synthesis was performed using N-[(1,1'-biphenyl)-4-ylmethyl]-1H-imidazol-1-amine as starting material which was reacted with the proper arylmethyl halide. Most of the newly synthesized imidazolamines exhibited both fungal growth inhibition activity and cellular selectivity.     

Synthesis and preliminary evaluation activity studies of novel 4-(aryl/heteroaryl-2-ylmethyl)-6-phenyl-2-[3-(4-substituted-piperazine-1-yl)propyl]pyridazin-3(2H)-one derivatives as anticancer agents

A series of new 4-(aryl/heteroaryl-2-ylmethyl)-6-phenyl-2-[3-(4-substituted piperazine-1-yl)propyl] pyridazin-3(2H)-one derivatives were synthesized. The structures of the compounds were confirmed by IR, ¹H NMR, and mass spectral data. All the compounds were evaluated for their cytotoxicity toward five human cancer cell lines of different origins viz; HeLa (Cervical), SKBR3 (Breast), HCT116 (Colon), A375 (Skin) & H1299 (Lung) at different concentrations and the IC₅₀ values were determined. HCT116 and HeLa are the most sensitive against the compounds studied. One of them displayed moderate cytotoxicity against SKBR3. Majority of the compounds exhibited good to moderate activity.     

Cardiotonic agents. 7. Prodrug derivatives of 4-ethyl-1,3-dihydro- 5-[4-(2-methyl-1H-imidazol-1-yl)benzoyl]-2H-imidazol-2-one.

The cardiotonic agent 4-ethyl-1,3-dihydro-5-4-(2-methyl-1H-imidazol-1-yl)benzoyl]-2H- imidazol-2-one (1) was found to have low bioavailability when administered orally to rats and dogs. A series of N-acyl derivatives, an underutilized prodrug of acidic NH compounds, has been synthesized and tested for their ability to improve the oral bioavailability of 1. Reaction of the monosodium salt of 1 with various anhydrides afforded the N-1 monoacylimidazolones with surprisingly high regioselectivity. In addition to the prodrugs, acylation of 1 with propionic or phenylacetic anhydride led to the novel 3H-pyrrolo[1,2-c]imidazole-3,5(2H)-diones 6. The prodrugs showed a significant increase in the partition coefficients with a minor decrease in the aqueous solubility. The benzoyl derivative 4b exhibited the highest stability in both pH 1.5 and 7.4 buffer solutions. Further evaluation of 4b showed rapid conversion to 1 in canine plasma (t1/2 = 38 min), and human plasma (t1/2 = 10 min). Oral studies indicated that the bioavailability of 4b was increased to greater than 75% (compared to less than 20% for 1), and hemodynamic studies demonstrated that the selective inotropic profile of 1 was retained.     

An efficient and straight forward synthesis of (5S)-1-benzyl-5- (1H-imidazol-1-ylmethyl)-2-pyrrolidinone (MM1): a novel antihypertensive agent

Abstract  

(5S)-1-benzyl-5-(1H-imidazol-1-ylmethyl)-2-pyrrolidinone and its closely related analog was synthesized from (S)-pyroglutaminol and imidazole or substituted imidazole using Mitsunobu reaction as the key step.     

Selective thromboxane synthetase inhibitors. 2. 3-(1H-imidazol-1-ylmethyl)-2-methyl-1H-indole-1-propanoic acid and analogues

The preparation of a series of 3-(1H-imidazol-1-ylmethyl)-1H-indole-1-alkanoic acids is described. Several compounds were found to be more potent thromboxane synthetase inhibitors than the corresponding analogues lacking an acidic substituent. In the cases examined, compounds had no significant activity against PGI2 synthetase or cyclooxygenase, and introduction of the carboxylic acid substituent led to a reduction in activity against adrenal steroid 11 beta-hydroxylase. Compound 21 strongly inhibited thromboxane formation after iv administration to anesthetized rabbits and oral administration to conscious dogs. The compound had a long duration of action, and marked inhibition of thromboxane production was observed 15 h after oral administration of 1 mg/kg to conscious dogs.     

Antimicrobial activity of a new derivative: N-(4-chlorobenzyl)-2-(1H-imidazol-1-ylmethyl)benzenamine

The activity of a new antifungal agent, an imidazolylmethylaniline derivative (XX H), synthesized by the authors, has been studied in vitro and in vivo. Antimicrobial data, in comparison with miconazole, ketoconazole and bifonazole, show antimicotic activity. The results are discussed on the basis of structure-activity relationships.     

Synthesis and some pharmacological properties of 3-(4-phenyl-5-oxo-1,2,4-triazolin-1-ylmethyl)-1,2,4-triazolin-5-thione derivatives

In the reaction of (4-phenyl- or 3,4-diphenyl-5-oxo-1,2,4-triazeolin-1-ylmethyl)-carbohydrazide (IIa, IIb) with isothiocyanates the thiosemicarbazide derivatives [IIIa, b - IXa, b] were obtained. Cyclization of those compounds in the presence of 2% or 10% NaOH led to formation of derivatives with the 1,2,4-triazolin-5-thione system [Xa, b - XV[a, b]. Molecular structure proposed for this group of compounds was confirmed by X-ray structure analysis of Xa and XIVa. Compounds Xa, XIIa and XIVa were investigated pharmacologically for their central properties in mice. It was shown that only compound XIIa produced antinociceptive effects in mice.     

Synthesis and antimicrobial properties of 3-aryl-1-(1,1'-biphenyl-4-yl)-2-(1H-imidazol-1-yl)propanes as 'carba-analogues' of the N-arylmethyl-N-[(1,1'-biphenyl)-4-ylmethyl])-1H-imidazol-1-amines,a new class of antifungal agents

A new series of 3-phenyl-1-(1,1'-biphenyl-4-yl)-2-(1H-imidazol-1-yl)propane derivatives 2a-l (related to the antifungal bifonazole) was synthesized and tested for antimicrobial activity. A number of substituents on the phenyl ring were chosen to compare the relative biological properties with those of corresponding aza-analogues, previously described by us. The in vitro antifungal activities of the newly synthesized azoles were tested against several pathogenic fungi responsible for human disease. Test pathogens included representatives of yeasts (Candida albicans, Candida parapsilosis, Criptococcus neoformans), dermathophytes (Tricophyton verrucosum, Tricophyton rubrum, Microsporum gypseum) and moulds (Aspergillus fumigatus). Bifonazole and miconazole were used as reference drugs. Title compounds were prepared by alkylation of 1-biphenyl-4-yl-2-imidazol-1-yl-ethanone with the proper arylmethyl halide and subsequent reduction of corresponding ketones applying the Huang-Minlon modification of the Wolff-Kishner reaction.     

Ring substituted 3-phenyl-1-(2-pyrazinyl)-2-propen-1-ones as potential photosynthesis-inhibiting, antifungal and antimycobacterial agents

Four series of ring substituted (E)-3-phenyl-1-(2-pyrazinyl)-2-propen-1-ones were prepared by means of modified Claisen-Schmidt condensation of acetylpyrazines with aromatic aldehydes. The structures were confirmed by elemental analysis, IR, 1H NMR and 13C NMR spectra. The compounds were tested for specific biological properties and some derivatives exhibited photosynthesis-inhibiting, antifungal and antimycobacterial properties. The most pronounced effects were observed with compounds substituted with phenolic groups. Ortho-hydroxyl substituted derivatives were more potent than the corresponding para-hydroxyl substituted analogues.     

Antiallergic agents. 2. N-(1H-tetrazol-5-yl)-6-phenyl-2-pyridinecarboxamides

A new series of N-(1H-tetrazol-5-yl)-6-phenyl-2-pyridinecarboxamides was prepared to determine the effects of substituents on the benzene and pyridine rings on antiallergic activity in the rat passive cutaneous anaphylaxis (PCA) assay after oral administration. One member of this series, N-(1H-tetrazol-5-yl)-4-methyl-6-[4-(methylamino)-phenyl]-2- pyridinecarboxamide (231), has an ED50 value of 0.8 mg/kg po and is 85 times more potent than disodium cromoglycate (DSCG) on intravenous administration. Further evaluation of 231 as a clinically useful antiallergic agent is in progress.     

Synthesis of (E)-1-(5-chlorothien-2-yl)-2-(1H-imidazol-1-yl)ethanone 2,6-dichlorophenylhydrazone hydrochloride, a novel, orally active antifungal agent

The preparation, determination of isomeric configuration, and antifungal properties of (E)-1-(5-chlorothien-2-yl)-2-(1H-imidazol-1-yl)ethanone 2,6-dichlorophenylhydrazone hydrochloride (1) are described. In vitro, compound 1 has been shown to have activity against Candida albicans comparable with miconazole. When administered orally to animals with experimentally induced vaginal candidiasis or systemic candidiasis, compound 1 produced results approaching those produced by ketoconazole. In addition, topical administration of compound 1 to rats with vaginal candidiasis produced results comparable with those produced by similar administration of clotrimazole. Unlike ketoconazole, which is active by a mechanism that is essentially fungistatic, compound 1 shares with miconazole a mode of action that is fungicidal. However, unlike miconazole, compound 1 exhibits activity following oral administration. Compound 1 has been found to be negative in the Ames test.