0000000000142591

AUTHOR

Riccardo Castelli

Synthesis and Structure-Activity Relationships of Amino Acid Conjugates of Cholanic Acid as Antagonists of the EphA2 Receptor

The Eph–ephrin system plays a critical role in tumor growth and vascular functions during carcinogenesis. We had previously identified cholanic acid as a competitive and reversible EphA2 antagonist able to disrupt EphA2-ephrinA1 interaction and to inhibit EphA2 activation in prostate cancer cells. Herein, we report the synthesis and biological evaluation of a set of cholanic acid derivatives obtained by conjugation of its carboxyl group with a panel of naturally occurring amino acids with the aim to improve EphA2 receptor inhibition. Structure-activity relationships indicate that conjugation of cholanic acid with linear amino acids of small size leads to effective EphA2 antagonists whereas …

research product

Synthesis, Structural Elucidation, and Biological Evaluation of NSC12, an Orally Available Fibroblast Growth Factor (FGF) Ligand Trap for the Treatment of FGF-Dependent Lung Tumors

NSC12 is an orally available pan-FGF trap able to inhibit FGF2/FGFR interaction and endowed with promising antitumor activity. It was identified by virtual screening from a NCI small molecule library, but no data were available about its synthesis, stereochemistry, and physicochemical properties. We report here a synthetic route that allowed us to characterize and unambiguously identify the structure of the active compound by a combination of NMR spectroscopy and in silico conformational analysis. The synthetic protocol allowed us to sustain experiments aimed at assessing its therapeutic potential for the treatment of FGF-dependent lung cancers. A crucial step in the synthesis generated a c…

research product

Δ5-Cholenoyl-amino acids as selective and orally available antagonists of the Epheephrin system

The Eph receptor-ephrin system is an emerging target for the development of novel anti-angiogenic therapies. Research programs aimed at developing small-molecule antagonists of the Eph receptors are still in their initial stage as available compounds suffer from pharmacological drawbacks, limiting their application in vitro and in vivo. In the present work, we report the design, synthesis and evaluation of structure-activity relationships of a class of Δ(5)-cholenoyl-amino acid conjugates as Eph-ephrin antagonists. As a major achievement of our exploration, we identified N-(3β-hydroxy-Δ(5)-cholen-24-oyl)-L-tryptophan (UniPR1331) as the first small molecule antagonist of the Eph-ephrin syste…

research product

Amino Acid Derivatives as Palmitoylethanolamide Prodrugs: Synthesis, In Vitro Metabolism and In Vivo Plasma Profile in Rats

Palmitoylethanolamide (PEA) has antinflammatory and antinociceptive properties widely exploited in veterinary and human medicine, despite its poor pharmacokinetics. Looking for prodrugs that could progressively release PEA to maintain effective plasma concentrations, we prepared carbonates, esters and carbamates at the hydroxyl group of PEA. Chemical stability (pH 7.4) and stability in rat plasma and liver homogenate were evaluated by in vitro assays. Carbonates and carbamates resulted too labile and too resistant in plasma, respectively. Ester derivatives, prepared by conjugating PEA with various amino acids, allowed to modulate the kinetics of PEA release in plasma and stability in liver …

research product