Francine Pazini

Bioconversion of quercetin and rutin and the cytotoxicity activities of the transformed products

Quercetin and rutin are well-know flavonoids. In spite of this, the comprehension of their metabolism is still incomplete. In this work, the cytotoxic activity of quercetin and rutin and its metabolites produced by metabolism of filamentous fungi was investigated. Flavonoids metabolism was monitored by HPLC and LC-MS. Both flavonoids were extensively metabolized. Quercetin was converted into metabolite methylquercetin (2) and quercetin glucuronide (3) and rutin into metabolite rutin sulphate (5), methylrutin (6) and rutin glucuronide (7). Cytotoxic effects of rutin, quercetin and its metabolites were measured by MTT tetrazolium reduction test and the trypan blue exclusion assay on HL-60 leukemic cells. The results showed similar concentration-dependent cytotoxic effect for rutin and rutin sulphate (5), while no cytotoxic effect was detected with the metabolites 6 and 7. In relation to the quercetin and its metabolites the results showed that all compounds have a similar concentration-dependent inhibitory effect on HL-60 cells. These findings corroborate the literature, showing that bioconversion is a useful strategy for production of biological active metabolites.

Involvement of the NO/cGMP/KATP pathway in the antinociceptive effect of the new pyrazole 5-(1-(3-fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole (LQFM-021)

The pyrazol compounds are known to possess antipyretic, analgesic and anti-inflammatory activities. This study was conducted to investigate the peripheral antinociceptive effect of the pyrazole compound 5-(1-(3-Fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole (LQFM-021) and involvement of opioid receptors and of the NO/cGMP/K(ATP) pathway. The oral treatments in mice with LQFM-021 (17, 75 or 300 mg/kg) decreased the number of writhing. In the formalin test, the treatments with LQFM-021 at doses of 15, 30 and 60 mg/kg reduced the licking time at both neurogenic and inflammatory phases of this test. The treatment of the animals with LQFM-021 (30 mg/kg) did not have antinociceptive effects in the tail-flick and hot plate tests. Furthermore, pre-treatment with naloxone (3 mg/kg i.p.), L-name (10 mg/kg i.p.), ODQ (10 mg/kg i.p.) or glibenclamide (3 mg/kg i.p.) antagonized the antinociceptive effect of LQFM-021 in both phases of the formalin test. In addition, it was also demonstrated that the treatments of mice with LQFM-021(15, 30 and 60 mg/kg) did not compromise the motor activity of the animals in the chimney test. Only the highest dose used in the antinociceptive study promoted changes in the open field test and pentobarbital-induced sleep test, thus ruling out possible false positive effects on nociception tests. Our data suggest that the peripheral antinociception effects of the LQFM-021 were mediated through the peripheral opioid receptors with activation of the NO/cGMP/KATP pathway.

Chemoselective and Regiospecific Formylation of 1-Phenyl-1H-pyrazoles Through the Duff Reaction

Abstract The synthesis of formylated 1-phenyl-1H-pyrazole derivatives under the Duff reaction conditions is reported. Our results indicate that 1-phenyl-1H-pyrazole systems containing electron-withdrawing and electron-donating substituents at the phenyl moiety react under the Duff reaction conditions to furnish formylated derivatives in good yields. Supplemental materials are available for this article. Go to the publishers online edition of Synthetic Communications® to view the free supplemental file. GRAPHICAL ABSTRACT

Design of new dopamine D2 receptor ligands: biosynthesis and pharmacological evaluation of the hydroxylated metabolite of LASSBio-581.

LASSBio-581 is a N-phenylpiperazine derivative designed for the treatment of schizophrenia. In this study, four strains of filamentous fungi were screened for their capabilities to biotransform LASSBio-581. Cunninghamella echinulata ATCC 9244 was chosen to scale up the biosynthesis of the p-hydroxylated metabolite of LASSBio-581. The chemical structure of the metabolite was confirmed by NMR, LC-MS and X-ray crystallography. Binding studies performed on brain homogenate indicated that the p-hydroxylated metabolite can be considered more selective for dopamine receptors than LASSBio-581, and, therefore, can be used to design new selective dopamine inhibitors.

One step N-glycosylation by filamentous fungi biofilm in bioreactor of a new phosphodiesterase-3 inhibitor tetrazole

An efficient and rapid process for N-glycosylation of 5-(1-(3-fluorophenyl)-1H-pyrazol-4-yl)-2H-tetrazole-LQFM 021 (1), a new synthetic derivative of pyrazole with phosphodiesterase-3 (PDE-3) inhibitory action, vasorelaxant activity and low toxicity catalyzed by filamentous fungi biofilm in bioreactor was successfully developed. A maximum N-glycosyl yield of 68% was obtained with Cunninghamella echinulata ATCC 9244 biofilm in bioreactor with conditions of 25mgml(-1) of 1 in PDSM medium at 28°C for 96h. After extraction with ethyl acetate, the derivative was identified by Ultrahigh Resolution Mass Spectrometry and (1)H-(13)C HSQC/HMBC.