Synthesis, NMR kinetics and dynamic structure of a 17-mer heptaloop RNA hairpin carrying a 3--methyluridine nucleotide residue in the loop region.

A 17-mer RNA hairpin (5'GGGAGUAGCGGCUCCC3') carrying 3--methyluridine (m3U) at position (m3U7-RNA), designed to represent the anticodon stem-loop (ACSL) region of tRNAs to study an open loop state (O-state), was synthesized, purified by HPLC, and characterized by MALDI-ToF_MS and NMR methods. H-NMR data revealed primary (P-state in 56.1%), secondary (S-state in 43.

Preliminary results of a novel quorum sensing inhibitor against pneumococcal infection and biofilm formation with special interest to otitis media and cochlear implantation.

The purpose of the study is to assess the effect of a novel quorum sensing inhibitor (QSI), coded as 'yd 47', against otitis media and biofilm formation on Cochlear implants (CIs). Small pieces cut from cochlear implant were implanted under the skin in the retroauricular area on both sides of four guinea pigs. The implant pieces in the study and control sides were implanted in Streptococcus pneumoniae strain solution and saline, respectively.

Synthesis and biological activities of some 1,3-benzoxazol-2(3H)-one derivatives as anti-quorum sensing agents.

Antibiotics are commonly used to treat microbial infections. Due to misuse or large-scale use of antibiotics, many pathogens have gained resistance which makes antibiotic treatments ineffective. The discovery that many bacteria use quorum sensing (QS) to regulate their virulence factor and pathogenicity production makes the QS system an attractive target for antimicrobial therapy.

Use of the parmbsc0 force field and trajectory analysis to study the binding of netropsin to the DNA fragment (5'CCAATTGG)(2) in the presence of excess NaCl salt in aqueous solution.

The parmbsc0 force field was applied to study in detail the binding of netropsin, at a salt concentration of 0.28M Na(+), to the minor groove of an 8-mer (5'CCAATTGG)(2) DNA duplex forming a netropsin·DNA complex which previously has been characterized by X-ray crystallography, albeit with the use of closely related DNA duplexes. The X-ray structure revealed that the terminal guanidinium and amidinium groups of netropsin interact with the extreme ends of the palindromic AATT sequence of the receptor DNA.

NMR and amber analysis of the neamine pharmacophore for the design of novel aminoglycoside antibiotics.

The dependence of the solution structure of neamine on pH was determined by NMR and AMBER molecular dynamics methods at pD 3.3, pD 6.5, and pD 7.

Synthesis and biological evaluation of 4,5-diphenyloxazolone derivatives on route towards selective COX-2 inhibitors.

A series of 3-unsubstituted/substituted-4,5-diphenyl-2-oxo-3H-1,3-oxazole derivatives were prepared as selective cyclooxygenase-2 (COX-2) inhibitors. Among the synthesized compounds, 4-(4-phenyl-3-methyl-2-oxo-3H-1,3-oxazol-5-yl)benzensulfonamide (compound 6) showed selective COX-2 inhibition with a selectivity index of >50 (IC(50)COX-1=>100 microm, IC(50)COX-2=2 microm) in purified enzyme (PE) assay. Compound 6 also exhibited selective COX-2 inhibition in human whole blood assay.

Antiviral and antimicrobial activities of new nitrobutane derivatives.

It is known that some addition products of beta-nitrostyrenes exhibit potent antimicrobial activity. In order to investigate the effects of structural modifications on the biological properties, some new Michael type addition products of beta-ethyl-beta-nitrostyrenes were synthesized. In this study, eight new 1-[(2-aminophenyl)thio]-1-phenyl-2-nitrobutane (2) derivatives were synthesized by addition of 2-aminothiophenol to the double bond of beta-ethyl-beta-nitrostyrenes (1).

Synthesis and analgesic and anti-inflammatory activity of some new (6-acyl-2-benzoxazolinone and 6-acyl-2-benzothiazolinone derivatives with acetic acid and propanoic acid residues.

In this study for developing potent analgesic and anti-inflammatory compounds, we synthesized 6-acyl-2-benzoxazolinone and 6-acyl-2-benzothiazolinone derivatives with acetic acid and propanoic acid side chain, and performed preliminary screening of their in vivo analgesic and anti-inflammatory activities at a single dose of 100 mg/kg inmice by a p-benzoquinone-induced writhing test and a Carrageenaninduced hind paw edema model, respectively. We also determined their gastric ulceration effects in the tested animals. Propanoic acid derivatives were generally found to have higher analgesic and anti-inflammatory activities, and among them, 3-(6-benzoyl-2-benzothiazolinon-3-yl)propanoic acid (Compound 4 a) exhibited the highest analgesic and anti-inflammatory activity.

Studies on analgesic and anti-inflammatory activities of 1-dialkylaminomethyl-2-(p-substituted phenyl)-5-substituted benzimidazole derivatives.

In this study the analgesic and anti-inflammatory activity of 1,2,5-trisubstituted benzimidazole derivatives have been examined. Analgesic activities of these compounds were investigated by using the modified Koster test. Among the compounds synthesized especially compound 1g (1-diethylaminomethyl)-2-(p-chlorophenyl)-5-nitro benzimidazole hydrochloride) has shown higher activity than acetylsalicylic acid (ASA) and indometacin.

Synthesis and antimicrobial activity of 1-dialkylaminomethyl- 2-(p-substituted phenyl)-5-substituted benzimidazole derivatives.

1-(Dialkylaminomethyl)-2-(p-substituted phenyl)-5-substituted benzimidazole derivatives 1 have been synthesized by reacting 2-phenylbenzimidazole derivatives with formaldehyde and a secondary amine. The derivatives of 2-phenylbenzimidazole were obtained by reacting the bisulfide addition product of substituted benzaldehydes with 4-substituted-o-phenylenediamines. Their structures were confirmed by microanalysis, IR and NMR spectral analysis.