Synthesis and antibacterial activity of the new 9-aminoacridine, 10,11-dihydro-5H-dibenzo[b,f]azepine, polyfluoro 5,6-dihydro-1,3,5-oxadiazine derivatives]

Screening among 9-aminoacridine, 10,11-dihydro-5H-dibenz[b, f]azepine and polyfluoro 5,6-dihydro-1,3,5-oxadiazine derivatives allowed to isolate compounds with potential antibacterial activity. Schemes of the active compounds synthesis are given. The most important is the estimation of the oxydiazines activity against gram-positive microorganisms including methicillin-resistant staphylococci. Special attention is paid to the activity of iminodibenzyl derivatives against multiresistant gram-negative microorganisms.     

Synthesis and antibacterial activity of new 9-O-arylpropenyloxime ketolides

A novel series of 9-O-arylpropenyloxime ketolide was synthesized and evaluated for their antibacterial activity. This series of ketolide exhibited potent activity against clinically isolated gram-positive strains including Staphylococcus pneumoniae and Straptococcus Pyogenes.     

Synthesis and antibacterial activity of some new derivatives of pyrazole

In this study, we report the synthesis and antibacterial activity of a new series of 5-amido-1-(2,4-dinitrophenyl)-1H-4-pyrazolecarbonitriles. Our results show that all compounds exhibit antimicrobial activities against methicillin susceptible Staphylococcus aureus and methicillin resistant S. aureus with MIC values of 25.1 and 91.0 μM.     

Synthesis and antibacterial activity of new carbapenems containing isoxazole moiety

The synthesis and biological activity of a series of new 1beta-methylcarbapenems 1a-g containing 5'-isoxazolopyrrolidin-3'-ylthio derivatives as C-2 side chain are described. Most compounds exhibited potent and well-balanced antibacterial activity as well as high stability to DHP-I comparable to that of meropenem. 1e and 1c showed the best combination of antibacterial activity and stability to DHP-I, respectively.     

Synthesis and antibacterial activity of new long-chain-alkyl bile acid-based amphiphiles

The efficient synthesis of some bile acid-derived cationic amphiphiles with a flexible long hydrocarbon tail was investigated. Firstly, the modification on the side-chain carboxyl of bile acids was carried out efficiently by one-pot amidation of bile acids and a long-chain aliphatic amine in the presence of HOBt and DCC to introduce a flexible long hydrocarbon tail. Then the hydrophilic concave side of bile acids with hydroxyl groups was further modified into cationic groups for strengthening hydrophilicity. This strategy offered a very straightforward and efficient method for access to the designed amphiphiles in good overall yields. The preliminary results showed that an increase both in the length of the hydrophobic tail and in the number of charged groups resulted in a decrease in the CMC of bile acid-derived cationic amphiphiles. And the bile acid-derived cationic amphiphiles with a flexible longer hydrocarbon tail and more positive charges had the highest antibacterial and antimicrobial activity.     

Synthesis and antibacterial activity of new N-linked 5-triazolylmethyl oxazolidinones

A new series of N-linked 5-triazolylmethyl oxazolidinones with varying substitution at the piperazine nitrogen 4-position were synthesized and tested against a panel of Gram-positive and Gram-negative bacteria including clinical isolates. Most of the compounds showed excellent antibacterial activity against susceptible and resistant Gram-positive organisms. One of the compounds showed enhanced antibacterial activity against Moraxella catarrhalis.     

Synthesis,antiproliferative and antibacterial activity of new amides of salinomycin

A series of 11 novel amides of salinomycin were synthesized for the first time. All the obtained compounds were found to show potent antiproliferative activity against human cancer cell lines including the drug-resistant cancer cells. Four new salinomycin derivatives revealed good antibacterial activity against clinical isolates of methicillin-resistant Staphylococcus epidermidis (MRSE).     

Synthesis and antimicrobial activity of 2-fluorophenyl-4,6-disubstituted [1,3,5]triazines

A series of 2-fluorophenyl-4,6-disubstituted [1,3,5]triazines (1) and (2) were synthesized and evaluated for their antimicrobial activity against three representative gram-positive bacteria and two fungi. The structure–activity relationship (SAR) demonstrates that the 3- or 4-fluorophenyl component attached directly to the triazine ring was essential for activity. Of these compounds, 14, 15, and 25 demonstrated significant activity against all selected organisms compared to control. These compounds were generally nontoxic and may prove useful as antimicrobial agents.     

Synthesis and antiinflammatory activity of some new 1,3,5-trisubstituted pyrazolines bearing benzene sulfonamide

Nineteen new 2-pyrazoline bearing benzenesulfonamide derivatives were synthesized by condensing chalcones with 4-hydrazinonbenzenesulfonamide hydrochloride. Their chemical structures were proved by means of IR, ¹H NMR, ¹³C NMR, mass spectroscopic and elemental analyses data. These compounds were tested at dose of 20 mg/kg for their anti-inflammatory activity in carrageenan-induced rat paw edema model and volume of paw edema was measured at 0, 3 and 5 h. Two compounds 3k and 3l were found to be more active than celecoxib throughout the study (at 3 and 5 h). While two other compounds 3m and 3n showed more potent activity than celecoxib at 5 h. They are devoid of ulcerogenic potential when administered orally at a dose of 60 mg/kg. Compounds (3k–m) showed COX-1 and COX-2 inhibitory activity at 0.05 μM.     

Synthesis and antibacterial activity of eremomycin esters through the carboxyl group]

Methyl, benzyl and diphenylmethyl esters of the glycopeptide antibiotic eremomycin were obtained by its treatment with corresponding diazoalkanes. The esters have high antibacterial activity but are less active than the parent antibiotic.     

Synthesis and cytotoxic activity of trisubstituted-1,3,5-triazines

1,3,5-Triazine derivatives were screened for phototoxicity as well as the cytotoxic activities against leukemia and adenocarcinoma derived cell lines in comparison to the normal human keratinocytes. A simple and environmentally friendly procedure has been developed for the synthesis of 1,3,5-triazine derivatives under microwave irradiation in the presence of a HY zeolite. The catalyst can be recovered and reused. Thus, the procedure provides a simple and green synthetic methodology under environmentally friendly conditions. Structure-activity relationships between the chemical structures and antimycobacterial and photosynthesis-inhibiting activity of the evaluated compounds are also discussed.     

Synthesis and in vitro activity of new methylenepiperidinyl and methylenepyrrolidinyl oxazolidinone antibacterial agents

We have prepared and evaluated the antibacterial activities of a series of substituted methylenepiperidinyl and methylenepyrrolidinyl oxazolidinones against several gram-positive strains including the resistant strains of Staphyloccus and Enterococcus, such as MRSA, CRSA, MSSA and VRE. Some of them showed comparable or superior in vitro activities (MIC) to vancomycin.     

Synthesis and antibacterial activity of 4,5,6,7-tetrahydro-thieno[3,2-c]pyridine quinolones

Synthesis and antibacterial activity of a number of substituted 4,5,6,7-tetrahydro-thieno[3,2-c]pyridine quinolones is reported. The antibacterial activities were evaluated in standard in vitro MIC assay method. Some of the compounds showed in vitro (MIC) antibacterial activity comparable to those of Gatifloxacin, Ciprofloxacin, and Sparfloxacin.     

Synthesis and antibacterial activity of substituted 1,2,3,4-tetrahydropyrazino [1,2-a] indoles

A series of substituted 1,2,3,4-tetrahydropyrazino [1,2-a] indole derivatives have been synthesized and tested against the Gram positive and Gram negative strains of bacteria namely Staphylococcus aureus (MTCCB 737), Salmonella typhi (MTCCB 733), Pseudomonas aeruginosa (MTCCB 741), Streptomyces thermonitrificans (MTCCB 1824) and Escherichia coli (MTCCB 1652). All synthesized compounds showed mild to moderate activity. However, compounds 4d-f were found to have potent activity against pathogenic bacteria used in the study. Their MIC ranged from 3.75 to 60 microg/disc. In vitro toxicity tests demonstrated that toxicity of 4d-f was not significantly different than that of gentamycin. However, at higher concentration (1000-4000 microg/ml) difference was highly significant.     

Synthesis and antibacterial activity of new fluoroquinolones containing a cis- or trans-cyclohexane moiety

New quinolone derivatives bearing a cis- or trans-cyclohexane side chain at the C-7 position have been synthesized and evaluated for their antibacterial activities against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa using the agar dilution method. The activities of compound 53 against these three bacteria were superior to those of the reference drug lomefloxacin. Compounds bearing a cis-cyclohexane side chain generally exhibited greater antibacterial activity than their corresponding trans-isomers.     

Synthesis and antibacterial activity of some new non-proteinogenic amino acids containing thiazole residues

Some new thioamides and thiazoles have been synthesized using canavanine, S-cysteine, homo-S-cysteinesulfonamides and their N-omega aminoethylated derivatives as adducts in order to investigate the structure-antimicrobial activity relationships. The compounds showed substantial antibacterial activity in vitro against various gram-positive (Staphylococcus aureus, Bacillus cereus etc.) and gram-negative (Escherichia coli, Proteus vulgaris etc.) bacteria. These findings indicate that the presence of the thiazole residue is an essential factor for the antibacterial effect.     

Synthesis and antibacterial activity of linezolid analogues

Several new compounds of oxazolidinone class were designed and synthesized referring to the structure-activity relationship studies and the synthesis of Linezolid, and their antibacterial activity was studied.     

Synthesis and antibacterial activity of pyrroloaryl-substituted oxazolidinones

A novel series of oxazolidinones containing a pyrroloaryl substituent was synthesized and screened against a representative panel of susceptible and resistant Gram-positive bacteria. Several members of this series were found to have antibacterial activity comparable to or better than linezolid.     

Synthesis and antibacterial activity of egonol derivatives

Synthesis of egonol derivatives, 5-(3'-chloropropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 1, 5-(3'-bromopropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 2, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propanal 3, 5-(3'-iodopropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 4, 5-[3-(3'-bromopropyloxy) propyl]-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 5, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propylmethanoate 6, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propyloleate 7, 5-[3'-hydroxypropyl]-6-bromo-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 8, 4-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]butanenitrile 9, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propylbenzoate 10, 5-[3'-hydroxypropyl]-7-methoxy-3-nitro-2-(3',4'-methylenedioxyphenyl)benzofuran 11 and their antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Candida albicans and Escherichia coli are reported. The starting material egonol 5-[3'-(hydroxy)propyl]-7-methoxy-2-(3', 4'methylenedioxyphenyl)benzofuran was isolated from seeds of Styrax officinalis L. The structural elucidication of these compounds (1-11) was established using 1D ((1)H, (13)C), 2D NMR (HMBC, HMQC, COSY) and LCMS spectroscopic data. While egonol and some synthesised new compounds show similar antibacterial activity and MIC values against S. aureus, B. subtilis, C. albicans and E. coli, other new derivatives show different activity against S. aureus, B. subtilis, C. albicans and E. coli.     

Synthesis and in vitro antiproliferative and antibacterial activity of new thiazolidine-2,4-dione derivatives

In our present research, we synthesised new thiazolidine-2,4-diones (12–28). All the newly synthesised compounds were evaluated for antiproliferative and antibacterial activity. Antiproliferative evaluation was carried out using normal human skin fibroblasts and tumour cell lines: A549, HepG2, and MCF-7. The IC₅₀ values were determined for tested compounds revealing antiproliferative activity. Moreover, safety index (SI) was calculated. Among all tested derivatives, the compound 18 revealed the highest antiproliferative activity against human lung, breast, and liver cancer cells. More importantly, the derivative 18 showed meaningfully lower IC₅₀ values when compared to the reference substance, irinotecan, and relatively high SI values. Moreover, newly synthesised compounds were screened for the bacteria growth inhibition in vitro. According to our screening results, most active compound was the derivative 18 against Gram-positive bacteria. Therefore, it may be implied that the novel compound 18 appears to be a very promising agent for anticancer treatment.