ABSTRACT
The trans-sialidase of Trypanosoma cruzi (TcTS) is a surface enzyme that modifies the parasite glycocalyx covering it with sialic acid. This process is essential to adhesion and invasion mechanisms in life cycle of the protozoan in the human host, making TcTS a very attractive molecular target for drug design. Using the TcTS substrate 3'-sialyllactose as prototype, D-galactose-derived potential inhibitors of TcTS were designed using strategies of molecular modification. Ten new aryl galactosides modified at carbon-3 were synthesized employing classical carbohydrate chemistry and dibutyltin oxide method for regioselective 3-O-alkylations and evaluated against TcTS by spectrofluorimetry. The 4-methoxycarbonyl-2-nitrophenyl 3-O-carboxymethyl-ß-D-galactopyranoside was the most active compound inhibiting 21% of TcTS enzymatic activity at 1 mM.
Subject(s)
Drug Design , Enzyme Inhibitors/pharmacology , Galactose/pharmacology , Glycoproteins/antagonists & inhibitors , Neuraminidase/antagonists & inhibitors , Trypanosoma cruzi/enzymology , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Galactose/chemical synthesis , Galactose/chemistry , Glycoproteins/metabolism , Molecular Docking Simulation , Molecular Structure , Neuraminidase/metabolism , Structure-Activity RelationshipABSTRACT
Pectolinarin, a flavone heteroside, was isolated from Distictella elongata (Vahl) Urb. leaves ethanol extract, along with a mixture of ursolic, pomolic and oleanolic acids, besides ß-sitosterol. Their structures were established on the basis of spectral analysis (1H and 13C NMR, 1D and 2D) and they were compared with literature. This is the first report on the occurrence of this flavonoid in a species of the Bignoniaceae family.