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Rosalia Pascual

Publications and source records attributed to Rosalia Pascual.

5 recordsLinked to original sources

Solid-phase synthesis of a combinatorial library of dihydroceramide analogues and its activity in human alveolar epithelial cells.

Solid-phase synthesis of a small combinatorial library of dihydroceramide analogues as mixtures of erythro and threo diastereomers is described. Some dihydroceramide analogues cause growth arrest and apoptosis in a dose-dependent manner in human alveolar epithelial cells. This activity is likely due to the threo isomers, as evidenced by cellular studies with a pair of diastereomerically pure N-acyldihydrosphingosines. The apoptotic activity reported in this work provides information for the design of new compounds that may provide the basis for the generation of biochemical tools for the study of different pathologies where ceramide and/or dihydroceramide are involved.

Apoptosis↗

A medicinal-chemistry-guided approach to selective and druglike sigma 1 ligands.

Based on a medicinal-chemistry-guided approach, three novel series of druglike cycloalkyl-annelated pyrazoles were synthesized and display high affinity (pKi>8) for the sigma1 receptor. Structure-affinity relationships were established, and the different scaffolds were optimized with respect to sigma1 binding and selectivity versus the sigma2 receptor and the hERG channel, resulting in selective compounds that have Ki values (for sigma1) in the subnanomolar range. Selected compounds were screened for cytochrome P450 inhibition (CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4), metabolic stability (rat and human liver microsomes), and cell-membrane permeability (Caco-2). They showed favorable in vitro ADME properties as well as favorable calculated druglike and experimental physicochemical properties. Furthermore, compounds 7 f and 17 a, for example, displayed high selectivity (affinity) for the sigma1 receptor against a wide range of other receptors (>60). With these valuable tool compounds in hand, we are further exploring the role of the sigma1 receptor in relevant animal models corresponding to such medicinal indications as drug abuse, pain, depression, anxiety, and psychosis.

Animals↗

Analysis of selection methodologies for combinatorial library design.

We have implemented and adapted in Pralins (Program for Rational Analysis of Libraries in silico), the most popular sparse (cherry picking) and full array (sublibrary) selection algorithms: hierarchical clustering, k-means clustering, Optimum Binning, Jarvis Patrick, Pral-SE (partitioning techniques) and MaxSum, MaxMin, MaxMin averaged, DN2, CTD (distance-based methods). We have validated the program with an already synthesized three-component combinatorial library of FXR partial agonists characterized by standard computational chemistry descriptors as case study. This has let us analyze the goodness of both the partitioning techniques for space division and all the selection methodologies with respect to representativity in terms of population and space coverage for different selection sizes. Within the chemical space analyzed, both hierarchical clustering and Optimum Binning division strategies are found to be the most advantageous reference space divisions to be used in the subsequent population and space coverage studies. Complete hierarchical clustering appears also to be the preferred selection methodology for both sparse and full array problems. The full array restriction fulfillment can easily be overcome by convenient optimization algorithms that allow optimal reagent selection preserving > 90% of the population coverage.

Combinatorial Chemistry Techniques↗

2-Methoxy-6-oxo-1,4,5,6-tetrahydropyridine-3-carbonitriles: versatile starting materials for the synthesis of libraries with diverse heterocyclic scaffolds.

Heterocyclic demonstration libraries for agrochemical screening were prepared from the common intermediates 2-methoxy-6-oxo-1,4,5,6-tetrahydropyridine-3-carbonitriles (1), using standard solution-phase techniques. A total of 18 screening libraries were prepared in good to excellent yields. Several members of these libraries were active in the first level of agrochemical screening, especially in the fungicide screen.

Chemistry, Pharmaceutical↗

Design and analysis of a combinatorial library of HEPT analogues: comparison of selection methodologies and inspection of the actually covered chemical space.

A large virtual library of 125 396 HEPT analogues, built by combining all fragments present in the published 180-compound HEPT family, has been studied in terms of diversity criteria and the goodness of the 11 available standard diversity selection methods analyzed. All the algorithms under study, except Cell-based Density, have rank above a random selection of compounds, with Optimum and Standard Deviation based Binning and Cell-based Fraction algorithms being the best choices. Furthermore, analysis of the actually tested compounds has been performed to compare the traditional drug discovery methodology versus a rational selection of combinatorial libraries approach.

Journal Article↗