Biomedical subjects

M G Vigorita

Publications and source records attributed to M G Vigorita.

At least 19 recordsLinked to original sources

PubMed2004

Design and synthesis of DNA-intercalating 9-fluoren-beta-O-glycosides as potential IFN-inducers, and antiviral and cytostatic agents.

Novel 9-fluoren-beta-O-glycosides, designed as DNA-intercalating agents in structural correlation with antiviral tilorone and anticancer anthracyclines, have been prepared with yields in beta-anomers ranging between 25 and 63%. They have been screened for antiproliferative, immunostimulating and antiviral properties against HSV-1 and HSV-2 viruses. Compounds displaying significant antiviral activity against HSV-2 are acetylated 1 and deprotected 6 9-fluorenyl-O-d-arabinopyranoses, whereas 9-fluorenyl-O-d-glucopyranose 3 is the most effective on HSV-1 replication, followed by 1 and 6. The conformational properties of these compounds have been evaluated by molecular modelling techniques.

Antineoplastic Agents↗

PubMed2003

Chiral 3,3'-(1,2-ethanediyl)-bis[2-(3,4-dimethoxyphenyl)-4-thiazolidinones] with anti-inflammatory activity. Part 11: evaluation of COX-2 selectivity and modelling.

Anti-inflammatory/analgesic 3,3'-(1,2-ethanediyl)-bis[2-(3,4-dimethoxyphenyl)-4-thiazolidinones] 1, obtained as racemic mixtures (a) and mesoforms (b), have two equivalent stereogenic centres (C-2 and C-2') and exist as RR, SS and RS isomers. The enantioseparation of 1a provided the single enantiomers that displayed different in vitro cyclooxygenase-1/cyclooxygenase-2 selectivity ratios. In particular the dextrorotatory compound is a highly selective COX-2 inhibitor and the levorotatory one is moderately selective. Instead, RS-meso isomer (1b) exhibited similar levels of inhibitory activity on both COX isozymes. The diastereo- and enantioselectivity has been explained by molecular modelling of RR, SS and RS compounds into COX-1 and COX-2 binding sites. Theoretical results indicated SS>RS>RR affinity order towards COX-2 isoenzyme, in agreement with in vitro and previous in vivo pharmacological results.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2002

Synthesis and aldose reductase inhibitory activity of 5-arylidene-2,4-thiazolidinediones.

Several (Z)-5-arylidene-2,4-thiazolidinediones were synthesized and tested as aldose reductase inhibitors (ARIs). The most active of the N-unsubstituted derivatives (2) exerted the same inhibitory activity of Sorbinil. The introduction of an acetic side chain on N-3 of the thiazolidinedione moiety led to a marked increase in lending inhibitory activity, conducting to the discovery of a very potent ARI (4c), whose activity level (IC50=0.13 microM) was in the same range of Tolrestat. Moreover, the corresponding methyl esters (3), devoid of any acidic functionality, showed appreciable inhibitory activity similar to that of the N-unsubstituted compounds. It was also found that the substitution pattern on the 5-benzylidene moiety markedly influenced the activity of N-unsubstituted 2,4-thiazolidinediones 2, compounds with substituents at the meta position being generally more effective than the para-substituted ones; however, this SAR was not evidenced in acetates 3 and acids 4.

Aldehyde Reductase↗

PubMed2001

Synthesis and antiinflammatory, analgesic activity of 3,3'-(1,2-ethanediyl)-bis[2-aryl-4-thiazolidinone] chiral compounds. Part 10.

In this note, the synthesis and structure-activity relationships of a new series of 2R,2'R/2S,2'S and 2R,2'S-meso 3,3'-(1,2-ethanediyl)-bis[2-aryl-4-thiazolidinones] are described. Antiinflammatory activity was investigated by the carrageenin-induced paw edema test and analgesic activity by acetic acid writhing and hot plate tests in rats. All compounds displayed ulcerogenic effects and acute toxicity much lower than indomethacin and phenylbutazone. Meso isomers (b) showed better pharmacological profiles than corresponding racemates (a). Methoxy substitution patterns of the aryls on stereogenic carbons are generally the most favorable on the pharmacological profile.

Analgesics, Non-Narcotic↗

PubMed2001

Antimycobacterial in vitro activity of cobalt(II) isonicotinoylhydrazone complexes. Part 10.

Octahedral cobalt(II) complexes of isonicotinoylhydrazones, which were obtained from the primary antituberculous agent isoniazid, have been synthesised and characterised. Their antimycobacterial in vitro activity has been evaluated against Mycobacterium tuberculosis H37Rv: they exhibit MIC values ranging from < 0.1 to 0.39 microg/mL, showing them to be generally more active than previously reported analogous Cu(II) and Ni(II) complexes.

Animals↗

PubMed2001

Nickel(II) 2,6-diacetylpyridine bis(isonicotinoylhydrazonate) and bis(benzoylhydrazonate) complexes: structure and antimycobacterial evaluation. Part XI.

The reaction of 2,6-diacetylpyridine (dap) and isonicotinoyl- or benzoylhydrazide leads to bishydrazones H(2)dapin (1a) and H(2)dapb (1b), respectively. The condensation can either take place as a bimolecular kinetic process between the two reactants or as a monomolecular metal-templated synthesis in the presence of nickel(II) ions. In the latter case the reaction products are charged 2,6-diacetylpyridine bis(hydrazone) nickel(II) complexes, which can be easily deprotonated to neutral hydrazonates. Diffractometric analysis of one of these [Ni(dapb)](2) (8b) has shown a binuclear structure with two octahedral nickel(II) ions bridged by two helicoidal dap (bishydrazonates) in a spheroidal structure of C(2V) symmetry. The synthesized complexes 8 are promising as antimycobacterial agents against M. tuberculosis H37Rv. In particular, 8b displays significant activity (MIC=0.025 microg/mL) 10-fold higher than rifampin and equal to isoniazid, while its ligand is ineffective. Compound 8b is also capable of reducing HIV-induced cytopathogenic effect in human T(4 )lymphocytes.

Antitubercular Agents↗

PubMed2000

Isoniazid-related copper(II) and nickel(II) complexes with antimycobacterial in vitro activity. Part 9.

Isonicotinoylhydrazones 1, obtained by the primary antituberculous agent Isoniazid, have been used as monoanionic ligands (L) to prepare copper(II) 2 and nickel(II) 3 octahedral complexes of stoichiometry [MeL2(H2O)2]. Their antimycobacterial in vitro activity was evaluated against Mycobacterium tuberculosis H37Rv in comparison with the ligands. Complexes 2a, 2b, 2f, 3b, 3d and 3g displayed MIC values < or = 0.2 microg/mL.

Antitubercular Agents↗

PubMed1997

3,3'-Bi(1,3-thiazolidin-4-one) system. VIII. 3,3'-(1,2-Ethanediyl) derivatives and corresponding 1,1'-disulfones: synthesis, stereochemistry and antiinflammatory activity.

To deeply investigate the influence of lipophilicity, phenyl substitution patterns and stereo-chemistry on pharmacological profiles of chiral bisarylthiazolidinones, frequently endowed with stereoselective antiinflammatory, analgesic, antihistaminic activities, we synthesized and explored some 3,3'-(1,2-ethanediyl) analogues 1-4, along with their S-oxidized derivatives 5-8. Each derivative can be isolated as 2R, 2'R/2S, 2'S (a) and 2R, 2'S- or 2S, 2'R- meso (b) diastereomers, which were explored by means of carrageenin edema test, acetic acid writhing and hot plate tests, and also tested for gastrolesive potential and LD50. Independently of lipophilic and electronic features, disulfides 3b, 4b and disulfones 7a, 8a, 8b displayed interesting activity levels which appear to be mainly linked to the disubstitution pattern on benzenic rings.

Animals↗

PubMed1996

Halogenated isoniazid derivatives VI. Evaluation of anti-HSV-1 and anti-HIV-1 in vitro activities of fluorinated analogues.

The synthesis and evaluation of antiviral in vitro activity are reported of some 2'-(1-arylethyl)isonicotinohydrazides (5a-d) and N-(1-arylethyl)isonicotinohydrazonic acids (6a-d), obtained by reducing fluorinated acetophenone isonicotinoylhydrazones (2a-d) with sodium cyanoborohydride. These INH analogues, along with other ones previously prepared, i.e. benzaldehyde isonicotinoylhydrazones 1, 4-aryl-1-methoxyl-1-(4-pyridyl)-2,3-diaza-1,3-butadienes 3 and 5-aryl-4-methyl-2-(4-pyridyl)-delta 2-1,3,4-oxadiazolines 4, were assayed for anti-HSV-1 activity on the monoblastoid cell line U937. Only some compounds (1b, 1d, 4d and 4e) displayed a moderate antiherpetic activity. In addition, the reduced compounds 5 and 6, submitted to the anti-HIV-1 screening, did not display significant effects in reducing virus-induced cytopathogenicity. The cytotoxicity of all compounds has been assayed on Vero cells and some considerations in correlation with structure are discussed.

Animals↗

PubMed1995

2-(4-Pyridyl)-delta 2-1,3,4-oxadiazolines from isonicotinoylhydrazones and diazomethane as potential antimycobacterial and anti-HIV agents. V.

The 5-aryl-4-methyl-2-(4-pyridyl)-delta 2-1,3,4-oxadiazolines 3, previously synthesized along with isomer 4-aryl-1-methoxy-1-(4-pyridyl)-2,3-diaza-1,3-butadienes 2 from benzaldehyde isonicotinoylhydrazones and diazomethane, were tested for in vitro activity against both M. tuberculosis and some atypical mycobacterial strains as well as against human immunodeficiency virus (HIV-1). Some halophenyl derivatives, 3e, 3g, 3i, 3j, were found to display MIC ranges from 1 to 10 (micrograms/ml against H 37 Rv and a clinical isolate tubercular strain, whereas against M. avium (MAC) the MICs were higher than 20 micrograms/ml. When the combinations of oxadiazolines with ethambutol, acting as inhibitor of cell wall synthesis, were assayed on MAC strain a synergistic effect was demonstrated for 3g and 3h trifluoromethyl derivatives. The antimycobacterial profiles of 2 and 3 analogues are compared and discussed. As shown by compounds 2, no substantial anti-HIV in vitro activity was found in selected delta 2-oxadiazolines; a moderate cytotoxicity, however, appears to be a common property.

Anti-Bacterial Agents↗

PubMed1994

Halogenated isoniazid derivatives as possible antimycobacterial and anti-HIV agents--III.

As part of a research directed to the synthesis of novel isoniazid derivatives with potential activity on mycobacteria and HIV virus, the acetophenone-isonicotinoylhydrazones 3 and the 4-aryl-1-methoxy-1-(4-pyridyl)- 2,3-diaza-1,3-butadienes 5, obtained by reaction between isonicotinoylhydrazones and diazomethane, have been prepared and tested for such activities. Both classes of derivatives showed interesting growth inhibitory activity on non-tubercular mycobacteria, including the emerging M. avium. Such activity appears to be linked to fluorine and/or chlorine presence on benzene rings. In contrast, none of the compounds submitted to the anti-AIDS in vitro screening, displayed any protection against HIV-1 virus-induced cytopathic effect in T4-lymphocyte cell lines.

Antiviral Agents↗

PubMed1994

Trifluoromethylcontaining sulfanilamides. I. Synthesis and in vitro antibacterial activity.

In a wider research directed to improve pharmacological profiles of known anti-infective agents by introducing fluorine or trifluoromethyl groups, some sulfanilamides trifluoromethylsubstituted on N1 ring, were synthesized and examined for their in vitro activity against gram-positive and gram-negative bacteria. Two N1-trifluoromethylphenyl-sulfanilamides, 1 and 4, exhibited MIC values, against all tested bacteria, similar or lower than those of the "classical" sulfanilamides, assayed in comparison. The new sulfanilamide 4 appears to be the more interesting: in fact, the presence of p-aminobenzoic acid (PABA) in culture medium did not influence its MIC values and no synergy was observed with trimethoprim, suggesting mechanism of action different from that of known sulfanilamides.

Anti-Bacterial Agents↗

PubMed1994

Aminopyrazinyl derivatives: synthesis and evaluation of antiinflammatory and related activities.

Some amides, 1-substituted methylenediamines and 2-substituted thiazolidin-4-ones, all containing the aminopyrazinyl moiety, were synthesized and tested in the experimental models of acute and chronic inflammations and as potential analgesic agents. The first series of compounds are inactive, whereas the N,N'-di-(2-pyrazinyl)-methylene-diamines and the 3-(2'-pyrazinyl)-thiazolidinones 6, 7, 11, 12 and even more 16 and 17 were found to be endowed with antiinflammatory and analgesic properties and low acute toxicity, the two latter being the most interesting.

Animals↗

PubMed1994

3,3'-Bi-[1,3-thiazolidine-4-one] system. VII. Synthesis and SARS of some 2-heteroaryl derivatives with antiinflammatory and related activities.

In pursuing the research on the SARs of chiral 3,3'-Bi-[1,3-thiazolidine-4-one] system derivatives, two new structural modifications were explored, both having on chiral C atoms thienyl or 2/3 pyridyl groups which have been found to improve antiinflammatory and related activities in the previously studied 3,3'-(1,2-ethanediyl)bisthiazolidinones. In particular a trimetylene chain was introduced between N-3 and N-3' thus obtaining the 3,3'-(1,3-propanediyl) derivatives [type Ic compounds], whereas by elimination of a thiazolidinone ring the 2-heteroaryl-3-[2'(heteroarylidenamino) ethyl]-1,3-thiazolidine-4-one derivatives (type II compounds) were prepared. The new compounds were explored in vivo for their antiinflammatory, analgesic, antipyretic activities, as well as for acute toxicity and ulcerogenic effects. The results obtained don't allow us to draw any reliable SAR except that, by increasing the distance between thiazolidinonic rings, in Ic compounds, the pharmacological profile is not improved with respect to (1,2-ethanediyl) inferior homologs. Among compounds II, only the thienyl derivative 5 appears to have antiinflammatory and analgesic activities.

Acetates↗

PubMed1992

Halogenated isoniazid derivatives as possible antitubercular and antineoplastic agents. Note 1.

Halogenated arylhydrazones, 2-aryl-4-thiazolidinones and their 1,1-dioxides containing isoniazid (INI) moieties were prepared and explored for antimicrobial (against bacteria, Candida and mycobacteria) and antitumor activities. None of the tested compounds showed any marked antimicrobial effect. Furthermore, among the compounds submitted to NCI in vitro primary antitumor screening, those bearing 3-fluoro or -chlorophenyl substituents were found to possess selective inhibitory effects on the growth of non small cell lung cancer, whereas those with para-phenyl substituents displayed selective effects, sometimes statistically significant, against leukemias.

Antineoplastic Agents↗

PubMed1992

Fluorocontaining D-cycloserines. Synthesis and in vitro evaluation of antimicrobial and antiviral activities.

Some fluoroacylderivatives at the side chain NH2 of D-cycloserine were synthesized and evaluated in vitro for antimicrobial activity against bacteria and tubercular or non-tubercular mycobacteria. Against the used Gram-positive and Gram-negative strains only trifluoroacetamide 1 exhibited comparable MIC values and lower MBC values than those of parent antibiotic. Other fluoroacycloserines, inactive at all on these bacteria, were found to inhibit the growth of mycobacteria when tested in liquid media. The in vitro anti-Herpex Simplex virus type-2 (HSV-2) activity was also investigated on HEp-2 and Vero cells. The obtained results demonstrated an antiviral activity of the compounds 1 and 3 when tested on Vero cell-lines, whereas the same cycloserine is inactive.

Animals↗

PubMed1990

N-trifluoroacetyl derivatives as pharmacological agents. V. Evaluation of antiinflammatory and antimicrobial activities of some N-heterocyclic trifluoroacetamides.

Following the investigation on pharmacological aspects of N-trifluoroacetyl compounds some heterocyclic trifluoroacetamides were prepared and explored as potential antiinflammatory-analgesic and antimicrobial agents. The trifluoroacetamides 3, 4, 5, and 6 reached significant activity in the hot plate analgesic test; the same 4 and 5, along with 7 and 8 showed inhibitory properties in the adjuvant arthritis test; only 7 however, displayed a significant dose-dependent activity in the carrageenin edema test. In addition the parent heterocyclic amines were similarly explored for comparison. Test for antimicrobial activity were carried out in parallel. Among the examined compounds, only 4-aminomorpholine and 2-aminobenzimidazole were found active when assayed against gram+ and gram- bacteria and mycetes.

Animals↗

PubMed1989

N-trifluoroacetyl derivatives as pharmacological agents. IV--Antiinflammatory and related properties; antimicrobial activity of some polyaromatic trifluoroacetamides.

Taking into account both the analogy with the antiinflammatory triflamides and our previous observations on a series of trifluoroacetanilides active as acute and chronic antiinflammatory agents, the present series of polyaromatic N-trifluoroacetylderivatives were prepared. Their antiinflammatory and related properties as well as antimicrobial activity were evaluated. Few derivatives were found to display significant analgesic effects (hot plate test) whereas at 50 mg/kg all were devoid of antiinflammatory effects except the benzophenone derivative (III). Instead as regards the antimicrobial screening, a selective antimycoplasmal activity was revealed in six out of ten examined compounds.

Acetamides↗