Biomedical subjects

Juan C Ribas

Publications and source records attributed to Juan C Ribas.

5 recordsLinked to original sources

PubMed2005

In vitro antifungal properties structure-activity relationships and studies on the mode of action of N-phenyl, N-aryl, N-phenylalkyl maleimides and related compounds.

The synthesis, in vitro antifungal evaluation and structure-activity relationship studies of 14 compounds of the N-phenyl-, N-aryl-, N-phenylalkyl- maleimide and 3,4-dichloromaleimide series are reported. The compounds were evaluated against a panel of standardized yeasts and filamentous fungi as well as clinical isolates of Candida albicans. The activities of N-phenylalkyl-3,4-dichloromaleimide derivatives but not those of N-phenylalkyl-maleimide derivatives showed to be dependent on the length of the alkyl chain. N-Phenylpropyl-3,4-dichloromaleimide showed the broadest spectrum of action and lower minimal inhibitory concentrations (MIC) in all of the fungi tested. The nitrogen-carbon distance between the two rings seems to play an important role in the antifungal behavior of these compounds. The most active structure showed inhibited (1,3)beta-D-glucan and chitin synthases, enzymes that catalyze the synthesis of the major fungal cell-wall polymers.

Antifungal Agents↗

PubMed2004

Cell wall analysis.

The cell wall is a rigid structure essential for survival of the fungal cell. Because of its absence in mammalian cells, the cell wall is an attractive target for antifungal agents. Thus, for different reasons, it is important to know how the cell wall is synthesized and how different molecules regulate that synthesis. The Schizosaccharomyces pombe cell wall is mainly formed by glucose polysaccharides and some galactomannoproteins. Here, we describe a fast and reliable method to analyze changes in S. pombe cell wall composition by using specific enzymatic degradation and chemical treatment of purified cell walls. This approach provides a powerful means to analyze changes in (1,3)beta-glucan and (1,3)alpha-glucan, two main polysaccharides present in fungal cell walls. Analysis of cell wall polymers will be useful to search for new antifungal drugs that may inhibit cell wall biosynthesis and/or alter cell wall structure.

Cell Wall↗

PubMed2003

In vitro antifungal activity of new series of homoallylamines and related compounds with inhibitory properties of the synthesis of fungal cell wall polymers.

The synthesis, in vitro antifungal evaluation and SAR studies of 101 compounds of the 4-aryl-, 4-alkyl-, 4-pyridyl or -quinolinyl-4-N-arylamino-1-butenes series and related compounds, are reported here. Active structures showed to inhibit (1,3)-beta-D-glucan and mainly chitin synthases, enzymes that catalyze the synthesis of the major fungal cell wall polymers.

Allylamine↗

PubMed2003

Synthesis, in vitro/in vivo antifungal evaluation and structure-activity relationship study of 3(2H)-pyridazinones.

The synthesis, in vitro/in vivo antifungal evaluation and a structure-activity relationship (SAR) study of 3(2H)-pyridazinones was carried out. The results reported here may be helpful in the structural identification and understanding of the minimum structural requirements for these molecules acting as antifungal agents. In addition, the most active structure in this series was tested for its capacity of inhibiting Saccharomyces cerevisiae beta 1,3-glucan synthase and chitin synthase, enzymes that catalyze the synthesis of the major polymers of the fungal cell wall.

Administration, Topical↗

PubMed2002

In vitro inhibition of 1,3-beta-glucan synthase by glycolipids from convolvulaceous species.

Sixteen convolvulaceous glycolipids selected from the tricolorin (1 - 7) and orizabin (8 - 16) series, proved to be strong in vitro inhibitors of the enzyme that catalyzes the synthesis of 1,3-beta-D-glucan, a major polymer of fungal cell-walls. Results provide an insight into function of the specific structures of these complex macrocyclic lactones as inhibitors of the 1,3-beta-D-glucan synthase and open the possibility of using these compounds as starting points for the development of antifungal agents that act by inhibiting fungal cell-wall synthesis.

Antifungal Agents↗