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A series of 4-substituted-2-thiazolylhydrazone derivatives have been synthesized and tested in vitro for their human monoamine oxidase (hMAO) A and B inhibitory activity. Our findings confirmed that the substitution at C4 of the thiazole ring was important to obtain highly potent and selective hMAO-B inhibitors with IC50 values in the nanomolar range. Moreover, these derivatives were endowed with a reversible mechanism of enzyme inhibition. Molecular modelling studies were performed to rationalize the recognition of all inhibitors with respect to hMAO-A and -B isoforms., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Thirty-eight new (4-(4-substituted-phenyl/2,4-disubstituted-phenyl)-thiazol-2-yl)hydrazine derivatives were synthesized in good yield and assayed for their in vitro anti-Candida activity, compared to topical and systemic antifungal drugs, against twenty-two clinical isolates of Candida spp. The concurrent presence of aliphatic chains or cycloaliphatic rings at N1-hydrazine and a 4-methyl/4-methoxyphenyl at C4 position of the thiazole nucleus exhibited an interesting anti-Candida inhibitory activity. Moreover, some of the most active compounds showed synergistic antifungal effects and lower cell toxicity when combined with clotrimazole., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Human carbonic anhydrase (hCA) IX is involved in tumorigenesis and metastasis through pathways modulating extracellular pH regulation and cell adhesion control. As a consequence, hCA IX represents a promising antitumor target for the development of new drugs in order to treat/image hypoxic cancers, and different agents targeting hCA IX are currently in Phase I - III clinical trials. Among novel chemotypes, coumarins and their congeners were shown to be potent and selective hCA IX inhibitors (CAI) in vitro with an alternative mechanism of action in respect to sulfonamide-based inhibitors. Furthermore, treatment of mice harboring CA IX-positive 4T1 mammary tumors with these selective coumarin-based CA IX inhibitors resulted in significant reduction of tumor growth and metastasis formation in both spontaneous and experimental models of metastasis.

A new scaffold of hydrazothiazoles has been designed as monoamine oxidase (MAO) inhibitors combining the hydrazine moiety of iproniazid and the thiazole nucleus of glitazones, a class of peroxisome proliferator-activated receptor (PPAR)γ agonists recently co-crystallized with human MAO-B. The resulting derivatives were synthesized and assayed to evaluate their in vitro activity against both the A and B isoforms of hMAO. All compounds were shown to be selective hMAO-B inhibitors with IC(50) values in the low micromolar/high nanomolar range. Such results suggest that the hydrazothiazole scaffold could be considered as an interesting pharmacophore for the future design of new lead compounds as coadjuvants for the treatment of neurodegenerative diseases., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Here, we report on the simultaneous direct HPLC diastereo- and enantioseparation of 3-methylcyclohexanone thiosemicarbazone (3-MCET) on a polysaccharide-based chiral stationary phase under normal-phase conditions. The optimized chromatographic system was employed in dynamic HPLC experiments (DHPLC), as well as detection technique in a batch wise approach to determine the rate constants and the corresponding free energy activation barriers of the spontaneous, base- and acid-promoted E/Z diastereomerization of 3-MCET. The stereochemical characterization of four stereoisomers of 3-MCET was fully accomplished by integrating the results obtained by chemical correlation method with those derived by theoretical calculations and experimental investigations of circular dichroism (CD). As a final goal, a deepened analysis of the perturbing effect exercised by the stationary phase on rate constant values measured through DHPLC determinations as a function of the chromatographic separation factor α of the interconverting species was successfully accomplished. This revealed quite small deviations from the equivalent kinetic values obtained by off-column batch wise procedure, and suggested a possible effective correction of rate constants measured by DHPLC approach., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A large series of (4-substituted-thiazol-2-yl)hydrazine derivatives was synthesized in good yield and assayed for their in vitro human monoamine oxidase (hMAO) inhibitory activity and selectivity. Most of them showed inhibitory activity in the nanomolar range and hMAO-B selective inhibition higher than reference drugs, demonstrating our interest in this privileged scaffold. The structure-activity relationship of the different rings on the N1-hydrazine position indicated that a pyridine ring was preferred with the presence of electron-withdrawing substituents on the aryl group at C4 of the thiazole nucleus. The substituent on the α-carbon to the N1-hydrazine moiety (methyl or hydrogen) had a great influence on the activity and hMAO-B selectivity. Moreover, the reversibility of the enzyme inhibition for the best active compound was reported., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

Novel 1-(4-ethyl carboxylate-thiazol-2-yl)-3,5-di(hetero)aryl-2-pyrazoline derivatives were obtained by reacting 3,5-di(hetero)aryl-1-thiocarbamoyl-2-pyrazolines with the ethyl ester of α-bromo-pyruvic acid. The synthesized compounds were confirmed by spectroscopic data and assayed to evaluate their in vitro ability to inhibit both isoforms of human cyclooxygenase (hCOX). Some derivatives (compounds 5, 6, 13, 16, and 17) displayed promising selectivity against hCOX-1 in the micromolar range and were shown to have a selectivity index similar or better than the reference drugs (indometacin, diclofenac). The introduction of a phenyl or a 4-F-phenyl ring on the C5 associated with a 4-substituted phenyl or a heteroaryl group on the C3 of (4-substituted-thiazol-2-yl)pyrazoline derivatives improved the activity against hCOX-1. Thanks to these preliminary results it could be possible to extend our knowledge of the pharmacophoric requirements for the discovery of new pyrazoline-based hCOX-1 inhibitors., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Urothelial cell carcinoma is one of the most common malignancies of the urinary tract. The standard of care, intravesical chemo- and immunotherapy, while effective, is associated with a considerable side-effect profile and approximately 30% of patients either fail to respond to treatment or suffer recurrent disease within 5 years. In the setting of muscle-invasive urothelial carcinoma, use of neoadjuvant chemotherapy is associated with overall survival benefit. Muscle invasive bladder cancer is life threatening, showing modest chemosensitivity, and usually requires radical cystectomy. Although bladder cancer is fairly well-genetically characterized, clinical trials with molecularly targeted agents have, in comparison to other solid tumors, been few in number and largely unsuccessful. Hence, bladder cancer represents a considerable opportunity and challenge for alternative therapies. In this review, we will focus on promising global or pathway-based approaches (epigenetic modulators, kinase inhibitors, angiogenesis blockage, peroxisome proliferator-activated receptor γ agonists, apoptosis inductors, virus therapy) supported by a deeper understanding of molecular biology of urothelial carcinoma, which have been recently tested in clinical trials.

Introduction: Monoamine oxidase (MAO) plays an important role in the control of intracellular concentration of monoaminergic neurotransmitters or neuromodulators and dietary amines. The rapid degradation of these molecules ensures the proper functioning of synaptic neurotransmission and is critical for the regulation of several mental and cognitive functions. The by-products of MAO-mediated reactions comprehend reactive and toxic chemical species. As a consequence of this, the development of human MAO inhibitors led to important discoveries in the treatment of several neuropsychiatric and neurodegenerative disorders., Areas Covered: This review highlights the recent MAO inhibitors-related patents (2010-2012) and reports on new associations of already known MAO inhibitors with other drugs, innovative therapeutic targets, MAO inhibitors obtained by plants extraction, alternative administration routes and synthetic processes., Expert Opinion: MAO inhibitors appear promising for further clinical development being often endowed with other pharmacological functions (iron-chelating property, cholinesterase inhibition). A new 'golden age' of MAO inhibitors recently started from (i) the discovery of new therapeutic targets (prostate cancer, diabetes, ischemia/reperfusion injury, tobacco dependence, transmissible spongiform encephalopathy); (ii) the recognized role of MAO as biomolecular markers (insomnia, chronic alcoholism, obsessive-compulsive behavior); (iii) the activity of these enzymes in other tissues (platelets, prostate cells).

Novel (4-(4-iodophenyl)-thiazol-2-yl)hydrazine derivatives were assayed for their in vitro anti-Candida activity, compared to topical and systemic antifungal drugs, against twenty-seven clinical isolates. The presence of aliphatic chains or specific heteroaromatic rings on hydrazone moiety at position C2 and a 4-iodophenyl at C4 of the thiazole ring gave a promising inhibitory activity especially against Candida albicans and Candida krusei. The most active compounds have been also evaluated for their cytotoxicity and in association with clotrimazole for anti-Candida activity., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

Purpose: We previously identified novel thiazole derivatives able to reduce histone acetylation and histone acetyltransferase (HAT) activity in yeast. Among these compounds, 3-methylcyclopentylidene-[4-(4'-chlorophenyl)thiazol-2-yl]hydrazone (CPTH6) has been selected and used throughout this study., Experimental Design: The effect of CPTH6 on histone acetylation, cell viability and differentiation, cell-cycle distribution, and apoptosis in a panel of acute myeloid leukemia and solid tumor cell lines has been evaluated., Results: Here, we showed that CPTH6 leads to an inhibition of Gcn5 and pCAF HAT activity. Moreover, it inhibits H3/H4 histones and α-tubulin acetylation of a panel of leukemia cell lines. Concentration- and time-dependent inhibition of cell viability, paralleled by accumulation of cells in the G(0)/G(1) phase and depletion from the S/G(2)M phases, was observed. The role of mitochondrial pathway on CPTH6-induced apoptosis was shown, being a decrease of mitochondrial membrane potential and the release of cytochrome c, from mitochondria to cytosol, induced by CPTH6. Also the involvement of Bcl-2 and Bcl-xL on CPTH6-induced apoptosis was found after overexpression of the two proteins in leukemia cells. Solid tumor cell lines from several origins were shown to be differently sensitive to CPTH6 treatment in terms of cell viability, and a correlation between the inhibitory efficacy on H3/H4 histones acetylation and cytotoxicity was found. Differentiating effect on leukemia and neuroblastoma cell lines was also induced by CPTH6., Conclusions: These results make CPTH6 a suitable tool for discovery of molecular targets of HAT and, potentially, for the development of new anticancer therapies, which warrants further investigations., (©2011 AACR.)

Among different heterocyclic chemotypes incorporating two nitrogen atoms, pyrazolines could be considered a valid pharmacophore for the synthesis of selective monoamine oxidase (MAO) inhibitors because they were developed by the cyclization of the early hydrazine derivatives such as isocarboxazid. Substituted pyrazolines, decorated with different functional groups, are important lead compounds endowed with a large amount of biological activities. As a matter of this, most of them were also evaluated as dual inhibitors with a synergistic action towards different classes of enzymes (ciclooxygenase, acetylcholinesterase, butyrylcholinesterase). Moreover due to the direct correlation with the recognized MAO inhibition, this scaffold displayed antidepressant and anticonvulsant properties in animal models.

The transcriptional peroxisome proliferator-activated receptor γ (PPARγ) co-activator PGC-1α plays a central role in the regulation of cellular energy metabolism. Among the wide range of its activities, PGC-1α controls mitochondrial biogenesis and function and is one of the main factors involved in hormonal and nutrient regulation of hepatic gluconeogenesis. PGC-1α is present in a multiprotein complex, and its activity can also be modulated through epigenetic modifications. In particular, it is directly acetylated by the HAT enzyme general control nonderepressible 5 (GCN5), resulting in a transcriptionally inactive protein that relocalizes from promoter regions to nuclear foci, whereas it is deacetylated by SIRT1 at multiple lysine sites, with a subsequent increase in its activity leading to induction of liver gluconeogenic gene transcription. Thus, both GCN5 and SIRT1 may be pharmacological targets to regulate the activity of PGC-1α, providing a potential treatment for metabolic disorders in which hepatic glucose output is altered.

Several 3-carbonyl (1-26), 3-acyl (27-52), and 3-carboxyhydrazido (53-58) coumarins have been synthesized in high yields (72-99%) and tested in vitro for their human monoamine oxidase A and B (hMAO-A and hMAO-B) inhibitory activity. Different substituents on the coumarin nucleus were evaluated for their effect on biological activity and isoform selectivity. Substitution at position C7 of the 3-ethyl ester coumarin ring, or the introduction of a hydrazido substituent at C3, were important to obtain highly potent and selective hMAO-B inhibitors with IC(50) values in the nanomolar range. Some derivatives were also submitted to a stability test and showed no chemical cleavage in vitro., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Monoamine oxidase plays a significant role in the control of intracellular concentration of monoaminergic neurotransmitters or neuromodulators and dietary amines. The rapid degradation of these molecules ensures the proper functioning of synaptic neurotransmission and is critically important for the regulation of emotional and other brain functions. The development of human MAO inhibitors led to important breakthroughs in the therapy of several neuropsychiatric disorders. Different families of heterocycles containing 2 or 4 nitrogen atoms have been used as scaffolds for synthesizing selective monoamine oxidase inhibitors, but the early period of the MAO-inhibitors started with hydrazine derivatives. Pyrazole, pyrazoline, and pyrazolidine derivatives can be considered as a cyclic hydrazine moiety. This scaffold also displayed promising antidepressant and anticonvulsant properties as demonstrated by different and established animal models. Diversely substituted pyrazoles, embedded with a variety of functional groups, are important biological agents and a significant amount of research activity has been directed towards this chemical class.

A new series of [4-(4'-substituted-phenyl)thiazol-2-yl]hydrazine derivatives were synthesized in good yield (86-99%) and characterized by elemental analysis, IR, (1)H NMR, and mass spectral studies. The compounds were assayed for their in vitro broad-spectrum antifungal activity, compared to clotrimazole and fluconazole, against 20 clinical isolates of pathogenic Candida spp., representing five different species. The results showed that the presence of heterocyclic or bicyclic rings on hydrazone moiety in position C2 of thiazole revealed a promising selective inhibitory activity especially against Candida albicans and Candida glabrata., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

Novel 1-(4-arylthiazol-2-yl)-2-(3-methylcyclohexylidene)hydrazine derivatives have been investigated for their ability to inhibit selectively the activity of the human B isoform of monoamine oxidase. These compounds were obtained as racemates and (R)-enantiomers by a stereoconservative synthetic pattern in high yield and enantiomeric excess. The (S)-enantiomers of the most active derivatives have been separated by enantioselective HPLC. All compounds showed selective activity against hMAO-B with IC(50) ranging between 21.90 and 0.018 microM.

N-substituted-3-carboxamido-coumarin derivatives were prepared and evaluated for selective antibacterial activity against 20 isolates of Helicobacter pylori clinical strains, including five metronidazole resistant ones. Some of them possessed the best activity against H. pylori metronidazole resistant strains with MIC values lower than the drug reference (metronidazole). Furthermore, anti-inflammatory activity through the inhibition of the IL-8 production was investigated., (2010 Elsevier Ltd. All rights reserved.)

A new series of [4-(3-methoxyphenyl)-thiazol-2-yl]hydrazyne derivatives were synthesized in good yield (71-99%) and characterized by elemental analysis and (1)H NMR studies. The compounds were assayed for their in vitro human monoamine oxidase (hMAO) inhibitory activity and selectivity and most of them showed IC(50) values in the nanomolar range, thus demonstrating our interest in this privileged scaffold. The most active and selective derivative (20), bearing a pyridine moiety on the CN, displayed IC(50)=3.81+/-0.12 nM and selectivity ratio=119 toward hMAO-B. Molecular modeling studies were carried out on recent and high resolution hMAO-A and hMAO-B crystallographic structures to better justify the enzyme-inhibitor interaction toward hMAO isoforms and to explain the structure-activity relationship of this kind of inhibitors., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

The present study reports on synthesis in high yields (70-99%), HPLC enantioseparation, inhibitory activity against human monoamino oxidases, and molecular modeling including 3D-QSAR studies, of a large series of (4-aryl-thiazol-2-yl)hydrazones (1-45). Most of the synthesized compounds proved to be potent and selective inhibitors of hMAO-B isoform in the micromolar or nanomolar range, thus demonstrating that hydrazothiazole could be considered a good pharmacophore to design new hMAO-B inhibitors. Due to the presence in some derivatives of a chiral center, we also performed a semipreparative chromatographic enantioseparation of these compounds obtained by a stereoconservative pattern. The separated enantiomers were submitted to in vitro biological evaluation to point out the stereorecognition of the active site of the enzyme towards these structures. Finally, a 3D-QSAR study was carried out using Comparative Molecular Field Analysis (CoMFA), aiming to deduce rational guidelines for the further structural modification of these lead compounds., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

Importance of the Field: Monoamine oxidase (MAO) plays a significant role in the control of intracellular concentration of monoaminergic neurotransmitters or neuromodulators and dietary amines. The rapid degradation of these molecules ensures the proper functioning of synaptic neurotransmission and is critically important for the regulation of emotional and other brain functions. Furthermore, modulators of neurotransmitters exert pleiotropic effects on mental and cognitive functions. The by-products of MAO-mediated reactions include several chemical species with neurotoxic potential. It is widely speculated that prolonged or excessive activity of these enzymes may be conducive to mitochondrial damages and neurodegenerative disturbances. In keeping with these premises, the development of human MAO inhibitors has led to important breakthroughs in the therapy of several neuropsychiatric disorders., Areas Covered in This Review: This review highlights the recent MAO inhibitors related patents published from July 2005 to December 2009. It also reports on new associations of already known MAO inhibitors with other drugs, innovative therapeutic targets, MAO inhibitors obtained by plants extraction, alternative administration routes and synthetic processes., What the Reader Will Gain: The reader will gain an overview of the main structures being investigated and their biological activities., Take Home Message: Several of these MAO inhibitors appear promising for further clinical development.

A series of N1-thiocarbamoyl-3,5-di(hetero)aryl-4,5-dihydro-(1H)-pyrazole derivatives has been synthesized and assayed for their ability to inhibit the activity of the A and B isoforms of human monoamine oxidase (hMAO). Some of these compounds were endowed with a selective inhibitory activity against hMAO-B in the micromolar range. The most active of the series is the compound 13, N1-thiocarbamoyl-3-(fur-2'-yl)-5-(4'-fluoro-phenyl)-4,5-dihydro-(1H)-pyrazole, with IC(50) 2.75+/-0.81muM value and selectivity ratio of 25, which is the best candidate for further investigations., (Copyright 2009 Elsevier Masson SAS. All rights reserved.)

A new series of 4-acyl-2-thiazolylhydrazone derivatives was synthesized and screened for its in vitro activity against Toxoplasma gondii. We evaluated parasite growth inhibition and cytotoxicity, inhibition of replication, and inhibition of parasite invasion of host cells. The biological results indicated that some substances had an antiproliferative effect against intracellular T. gondii tachyzoites cultivated in vitro.

A large series of 3-carboxamido-7-substituted coumarins have been synthesized and tested in vitro for their human monoamine oxidase A and B (hMAO-A and hMAO-B) inhibitory activity. Taking into account all the relevant structural information on MAOs reported in the literature, we made some changes in the coumarin nucleus and examined with particular attention the effect on activity and selectivity of substituting at position 3 with N-aryl or N-alkyl carboxamide and at position 7 with a benzyloxy or a 4'-F-benzyloxy group. Some of the assayed compounds proved to be potent, selective inhibitors of hMAO-B with IC(50) values in the micromolar range. To better understand the enzyme-inhibitor interaction and to explain the selectivity of the most active compounds toward hMAOs, molecular modeling studies were carried out on new, high resolution, hMAO-A and hMAO-B crystallographic structures.

Acetylation is a key modulator of genome accessibility through decondensation of the chromatin structure. The balance between acetylation and opposite deacetylation is, in fact, a prerequisite for several cell functions and differentiation. To find modulators of the histone acetyltransferase Gcn5p, we performed a phenotypic screening on a set of newly synthesized molecules derived from thiazole in budding yeast Saccharomyces cerevisiae. We selected compounds that induce growth inhibition in yeast strains deleted in genes encoding known histone acetyltransferases. A novel molecule CPTH2, cyclopentylidene-[4-(4'-chlorophenyl)thiazol-2-yl)hydrazone, was selected based on its inhibitory effect on the growth of a gcn5Delta strain. We demonstrated a specific chemical-genetic interaction between CPTH2 and HAT Gcn5p, indicating that CPTH2 inhibits the Gcn5p dependent functional network. CPTH2 inhibited an in vitro HAT reaction, which is reverted by increasing concentration of histone H3. In vivo, it decreased acetylation of bulk histone H3 at the specific H3-AcK14 site. On the whole, our results demonstrate that CPTH2 is a novel HAT inhibitor modulating Gcn5p network in vitro and in vivo.

A series of 2-methylcyclohexylidene-(4-arylthiazol-2-yl)hydrazones have been investigated for their ability to inhibit selectively the activity of the human A and B isoforms of monoamine oxidase (MAO). The target compounds, which present a stereogenic center on the cyclohexane ring, were obtained as pure (R) and (S) enantiomers by enantioselective HPLC. The absolute configuration of homochiral forms isolated on a semipreparative scale was obtained by a combined strategy based on chemical correlation and single-crystal X-ray diffraction. All compounds showed higher activity against the human MAO-B isoform with IC50 values ranging between 26.81 +/- 2.74 microM and 14.20 +/- 0.26 nM, and the assays carried out on the pure enantiomers showed higher activity for the (R) form. A computational study was performed by molecular mechanics, DFT-based quantomechanics, and docking techniques on the most active and human MAO-B selective inhibitor 8.

Objective: To evaluate the prevalence and incidence of nephrotoxicity in HIV-infected patients enrolled in the SCOLTA Project tenofovir cohort and to identify possible risk factors., Design: The SCOLTA Project is a prospective, observational, multicenter study involving 25 infectious disease departments in Italy created to assess the incidence of severe adverse events in patients receiving new antiretroviral drugs., Patients: The SCOLTA Project tenofovir cohort includes a total of 754 HIV infected patients., Results: Data including grade II-IV creatinine elevations according to ACTG scale were available in 354 patients, 237 (67%) males with a mean age of 40.1+/-7.6 years enrolled in the SCOLTA Project tenofovir cohort. During a mean follow up of 19.5+/-11.5 months creatinine elevations were reported in 9/354 (2.5%) patients, all males. Mean duration of tenofovir therapy at the event was 9.5+/-5 months. The overall incidence was 1.6 (95% CI 1.5-1.7) per 100 person-years (p-y) and 0.5 (95% CI 0.4-0.6) p-y for grade III. No grade IV creatinine elevations were reported. Patients with nephrotoxicity were older and more frequently male, HCV infected, in CDC stage C and their CD4 cell count was significantly lower than those without nephrotoxicity. No significant difference was found between tenofovir co-administered antiretroviral drugs., Conclusions: Both prevalence and incidence of nephrotoxicity were low in patients receiving tenofovir in a non-selected clinical setting. Renal injury in patients receiving tenofovir seems associated with the presence of co-morbidities and with advanced HIV infection.

Background: It is not known whether antiretroviral therapy (ART) including lopinavir/r has a different effect on the lipid metabolism in HIV patients co-infected with HCV. This study investigated changes in lipid levels, comparing patients with HIV infection alone and those with HCV too, in the lopinavir/r cohort of the SCOLTA project., Methods: We analyzed the data for the lopinavir/r nationwide cohort from 25 Italian infectious disease departments, which comprises 743 HIV-infected patients followed prospectively, comparing subjects with HIV-HCV co-infection and those with single-infection., Results: At enrolment, co-infected patients had significantly lower mean cholesterol than HCV negative cases (162+/-43mg/dL vs. 185+/-52mg/dL, p=0.0009). Total and non-HDL cholesterol and triglycerides rose significantly from baseline in HIV single-infection patients, but not in those with co-infection. The patients with dual HIV-HCV infection, treated with an ART regimen including lopinavir/r, have only limited increases in total and non-HDL cholesterol and triglycerides., Conclusions: Changes in serum lipids in co-infected patients differed significantly from those in patients without HCV. It remains to be seen whether this is associated with a lower risk of progression of atherosclerotic disease.

Simultaneous HPLC diastereo- and enantioseparations of 2-methylcyclohexanone thiosemicarbazone (2-MCET) were accomplished on coated- and immobilized type polysaccharide-based chiral stationary phases (CSPs). The identification of all stereoisomeric forms and their stereochemistry were achieved by combining theoretical, HPLC and chiroptical data. The stereochemical stability of the target compound was studied by classical off-column and dynamic HPLC kinetic procedures and the influence of different parameters such solvent, TFA concentration and temperature on stereoisomerization process was evaluated. The findings obtained by chromatographic and kinetic experiments were used to develop a simple method to convert the racemic form of 2-MCET into a single enantiomer.

In this paper, we report on the synthesis of a novel series of 2-thiazolylhydrazone derivatives and the influence of the substituents on the thiazole ring on antifungal activity. All synthesized compounds were screened for their in vitro activities against 22 clinical isolates of Candida spp., representing six different species, compared to clotrimazole as a reference compound. Some of the tested compounds were found to possess significant antifungal activity when compared to clotrimazole, in particular compound 14 which exhibited higher potency against most of the Candida spp. considered. The compounds that were most active as anti-Candida agents were also submitted to cytotoxic screening by the Trypan Blue dye exclusion assay and in general they were shown to induce low cytotoxic effects.

A novel class of selective anti-Helicobacter pylori agents, 2-oxo-2H-chromene-3-carboxamide derivatives, were prepared and evaluated for their anti-bacterial activity. All synthesized compounds showed little or no activity against different species of Gram-positive and Gram-negative bacteria and against various strains of pathogenic fungi. Some of them exhibited a potent and specific inhibitory effect on the growth of H. pylori, including metronidazole-resistant strains, in the 0.0039-16 microg/mL MIC range. A cytotoxic screening by the Trypan blue dye exclusion assay was also carried out on the most active compounds as anti-H. pylori agents. Among the derivatives examined for their cytotoxic potential, a number of them induced low cytotoxic effects.

HIV-infected patients may undergo renal damage related to the HIV infection itself, to the presence of co-infections, arterial hypertension, diabetes or to the exposure to nephrotoxic drugs. Tenofovir has been associated with the development of acute renal failure with Fanconi syndrome and acute tubular necrosis and, albeit rarely, with chronic liver disease. Patients with low CD4 cell count, low body weight and with concomitant diseases such as arterial hypertension and diabetes or co-infections with HCV, HBV or Treponema pallidum seem at higher risk of tenofovir-related nephrotoxicity. Other risk factors include previous exposure to nephrotoxic drugs and the association of tenofovir with boosted protease inhibitors or with didanosine. However, from the analysis of published papers the incidence of tenofovir-related renal toxicity seems low, as confirmed also by our personal casuistry (SCOLTA Project). Thus, a careful selection of patients including the evaluation of existent renal disease before starting an antiretroviral regimen including tenofovir is necessary to prevent renal damage. Furthermore, frequent monitoring of renal function in patients at higher risk of renal damage is strongly recommended, as well as a tenofovir dose adjustment if an alteration of renal function is detected.

A novel series of N,N'-bis[2-oxo-2H-1-benzopyran]-3-carboxamide derivatives have been synthesized and investigated for the ability to inhibit the activity of the A and B isoforms of monoamine oxidase (MAO). Some of the synthesized compounds show good selective inhibitory activity against the MAO-A isoform. Both the MAO-A and -B isoforms, deposited in the Protein Data Bank as the 2BXR and 1GOS models, respectively, were considered in a computational study performed with docking techniques on the most active and selective inhibitors.

In order to develop new anti-Helicobacter pylori agents, five new and three already known N-substituted-2-oxo-2H-1-benzopyran-3-carboxamides (coumarin-3-carboxamides) were prepared and evaluated for their antibacterial activity. All synthesized compounds showed little or no activity against different species of Gram-positive and Gram-negative bacteria of clinical relevance and against various strains of pathogenic fungi. Among the prepared compounds those with a 4-acyl-phenyl group showed the best activity against H. pylori metronidazole resistant strains in the 0.25-1 microg/ml MIC range, indicating the presence of an acyl function as an important feature for activity.

The SCOLTA project (Surveillance Cohort Long-term Toxicity Antiretrovirals) is a system for online surveying of adverse reactions to recently commercialized antiretroviral drugs and a "sentinel" for unexpected and late adverse reactions arising during any antiretroviral treatment (available at: http://www.cisai.info). To date, 25 Italian departments of infectious diseases have participated at the project. The New Drugs Project is a prospective, multicenter, observational pharmacovigilance study involving 1 cohort of patients for each new drug. All patients who were consecutively started on lopinavir (LPV), tenofovir (TDF), peginterferon (IFN), atazanavir (ATZ), enfuvirtide (T-20), and tipranavir (TPV) were enrolled. All grade III or IV adverse events (according to the AIDS Clinical Trials Group definitions) are reported on the web site. The Unexpected Events Project identifies unexpected adverse reactions during treatment and reports them. This paper presents the preliminary findings for the New Drugs Project. Between October 1, 2002, and March 30, 2004, 1184 patients were enrolled. The lopinavir/ritonavir (LPV/r) cohort comprises 703 patients, the TDF cohort 585, IFN 35, ATZ 95, T-20 10, and TPV 8. So far 100 grades III and IV adverse events have been reported, 73 in the LPV/r group. In this cohort the rate of adverse events per 100 person-years was 14.2 on the basis of all patients treated, 9.8 for treatment-naive patients, and 15 for treatment-experienced patients. These findings, though preliminary, show that this data collection method gives timely real-life information from which to assess the impact of short- and long-term toxicity of new antiretroviral drugs.

Highly active antiretroviral therapy (HAART) greatly reduces the risk of developing tuberculosis for HIV-infected persons. Nonetheless, HIV-associated tuberculosis continues to occur in countries where HAART is widely used. To identify the characteristics of HIV-infected persons who develop tuberculosis in the context of the availability of HAART, the current authors analysed data taken from 271 patients diagnosed, in Italy, during 1999-2000. These patients represent 0.7% of the 40,413 HIV-infected patients cared for in the clinical units participating in this current study. From the data it was observed that 20 patients (7.4%) had a previous episode of tuberculosis whose treatment was not completed. Eighty-one patients (29.9%) were diagnosed with HIV at tuberculosis diagnosis, 108 (39.8%) were aware of their HIV status but were not on antiretroviral treatment and 82 (30.3%) were on antiretroviral treatment. Patients on antiretroviral treatment were significantly less immunosuppressed than patients with HIV diagnosed concurrently with tuberculosis, or other patients not on antiretrovirals (median CD4 lymphocytes count: 220 cells x mm(-3) versus 100 cells x mm(-3), and 109 cells x mm(-3), respectively). No significant differences in clinical presentation of tuberculosis according to antiretroviral therapy status were recorded. Failure of tuberculosis control interventions (e.g. noncompletion of treatment) and of HIV care (delayed diagnosis of HIV infection and suboptimal uptake of therapy) may contribute to continuing occurrence of HIV-associated tuberculosis in a country where highly active antiretroviral therapy is largely available. However, a significant proportion of cases occur in patients who are on antiretroviral treatment.

Purpose: This study set out to describe the frequency of lipodystrophy, and identify its risk factors, in HIV-positive patients treated with HAART containing at least one protease inhibitor (PI). We analyzed the data collected in the CISAI study., Methods: The CISAI is a multicenter cohort study that has enrolled 1480 patients. We assessed whether patients had lipodystrophy at a medical visit, with follow-up visits by the same physician at least every 2 months, and also on the basis of patients' own reports., Results: The lipodystrophy syndrome was detected in about 25% of the patients. Multivariate analysis showed the risk of lipodystrophy was correlated with female sex (RR 1.5; 95% confidence interval, CI, 1.2-2.1), with older age, with homosexuality (RR 1.5; 95% CI 1.0-2.4), with overt disease (RR 1.4; 95% CI 1.1-1.8) and with the duration of treatment before entering this study. The RR for ritonavir was higher than for the other PI (RR 1.4; 95% CI 0.9-1.9). Among patients receiving concomitant antiretroviral therapy the risk of lipodystrophy was greater with stavudine (RR 1.7; 95% CI 1.3-2.3)., Conclusions: The study confirmed the high frequency of the lipodystrophy syndrome among patients treated with PI.

The introduction of protease inhibitors has proven a watershed in human immunodeficiency virus infection therapy and has initiated an era of highly active antiretroviral therapy. However, the numerous data on the effectiveness of these therapeutic regimens have been cited with an ever-growing number of communications concerning adverse reactions. In particular, the widescale use of protease inhibitors has underlined a series of events not evidenced in the controlled clinical studies that permitted the registration of these drugs. We are conducting a cohort multicenter study to evaluate the incidence of adverse events during treatment with protease inhibitors. To date, 4 cases of bilateral osteonecrosis of the femoral head have been reported out of 1073 person-years. While the pathogenesis of this event is unclear, it may be a long-term complication of protease inhibitor treatment.

Purpose: To establish the exact cause and effect relationship between protease inhibitors (PIs) and adverse events., Materials and Method: Prospective, cohort, multicenter study on HIV-positive patients who are beginning treatment with a PI. Causal relationships are evaluated using the RUCAM algorithm., Results: Since the beginning of the study 1207 patients have been enrolled. Average time of observation is 10.7 months. To date, 784 adverse events have been observed, distributed as follows: excluded 3.8%, improbable 18.5%, possible 41.3%, probable 30.1%, and highly probable 6.3%. Saquinavir shows a statistically significant difference in the rate of non-correlated events with respect to other groups., Conclusions: Over 20% of adverse events during PI treatment are shown to be non-correlated to these drugs. Saquinavir shows the highest rate of non-correlated events.

The aim of our study is to compare the tolerability of zidovudine/lamivudine/indinavir when used in post-exposure prophylaxis (PEP) subjects and in HIV-infected patients. HIV-negative patients were enrolled as part of the surveillance protocol for professional exposure at the Luigi Sacco Hospital in Milan. HIV-positive patients were selected among all subjects undergoing treatment with zidovudine/lamivudine/indinavir from the CISAI cohort, an Italian cohort for the evaluation of adverse reactions to HAART. In both studies patients were followed prospectively and the severity of the reactions was evaluated using the AIDS Clinical Trial Group adverse experience grading scales. Up to September 1999, 37 HIV-seronegative subjects had undergone treatment with zidovudine/ lamivudine/indinavir. From a total of 1207 patients belonging to the CISAI cohort, 199 were identified as being treated with the same regimen. The frequency of adverse events in the PEP subjects was 70.3% compared to 11.1% for HIV-infected patients. In the first group, adverse events caused treatment interruption in 21 subjects (56.7%) versus 14 patients (7%) among the HIV-infected group. Only one case of a severe event (grade 3-4) was observed in the prophylaxis group against 12 in the treatment group. Our study shows that treatment interruption is eight times higher in HIV-negative subjects compared to HIV-seropositive patients, and that the incidence of adverse events is approximately six times higher, though such events, are for the most part, not severe.

Objective: To assess the probability that protease inhibitor (PI) therapy might be discontinued because of adverse events (AE) and to evaluate the incidence rate of adverse reactions during PI treatment., Design: A prospective cohort, multicenter study on HIV-positive patients starting treatment with at least one PI., Setting: Ten departments of infectious diseases in Northern Italy., Patients: A total of 1207 patients who started PI therapy in September 1997 and were consecutively observed up to April 1999., Main Outcome Measures: Adverse reactions following initiation of PI therapy, and time to therapy discontinuation due to AE., Results: During the study period, 35.9% patients presented adverse reactions of any grade, whereas 9.7% presented at least one serious AE. After 12 months of treatment, the percentage of patients who had interrupted treatment was 36% of ritonavir-treated patients, 14.2% of those treated with indinavir, 13.6% of ritonavir-saquinavir hard gel capsules (HGC)-treated patients, and 8.5% and 2.1%, respectively, for those treated with nelfinavir and saquinavir HGC. Women and patients with hepatitis experienced a significantly greater number of adverse events compared with other categories. Gastrointestinal events were more frequently observed in patients treated with either ritonavir alone or in combination with saquinavir HGC, as well as in patients receiving nelfinavir, although in this group serious events were rare. Here again, neurologic, metabolic, and hepatic toxicity occurred more frequently in ritonavir and ritonavir-saquinavir HGC treated patients. Allergic reactions were more often observed in patients receiving nelfinavir. Indinavir-treated patients presented the highest incidence of renal toxicity., Conclusion: Ritonavir is the drug associated with the largest number of reactions, which appear during the first few months of treatment. Saquinavir HGC and nelfinavir are the best tolerated drugs in a clinical setting.