Synthesis, biochemical, and biological evaluation of C2 linkage derivatives of amino sugars, inhibitors of glucokinase from Trypanosoma cruzi

• Published in: Bioorganic & medicinal chemistry letters 2021-09, Vol.47, p.128227-128227, Article 128227
• Main Authors: Green, Scott B., Lanier, Robert J., Carey, Shane M., Morgan, David R., Gracz, Hanna, Sherman, Julian, Rodriguez, Ana, D'Antonio, Edward L.
• Format: Article
• Language: English
• Subjects: Amino sugars; Amino Sugars - chemical synthesis; Amino Sugars - chemistry; Amino Sugars - pharmacology; Chagas’ disease; Dose-Response Relationship, Drug; Enzyme Inhibitors - chemical synthesis; Enzyme Inhibitors - chemistry; Enzyme Inhibitors - pharmacology; Glucokinase; Glucokinase - antagonists & inhibitors; Glucokinase - metabolism; Inhibitors; Molecular Structure; Neglected tropical diseases; Structure-Activity Relationship; Trypanosoma cruzi - enzymology
• ISSN: 0960-894X; 1464-3405
• DOI: 10.1016/j.bmcl.2021.128227

[Display omitted] •Novel amino sugar analogues were synthesized and purified in a one-step method.•Eighteen amino sugar analogues having either a d-GlcN, d-ManN, or d-GalN scaffold were screened against TcGlcK and a T. cruzi parasite infection of mammalian cells.•TcGlcK was notably inhibited by amino sugar analogues having the d-GlcN scaffold. Eighteen amino sugar analogues were screened against Trypanosoma cruzi glucokinase (TcGlcK), a potential drug-target of the protozoan parasite in order to assess for viable enzyme inhibition. The analogues were divided into three amino sugar scaffolds that included d-glucosamine (d-GlcN), d-mannosamine (d-ManN), and d-galactosamine (d-GalN); moreover, all but one of these compounds were novel. TcGlcK is an important metabolic enzyme that has a role in producing G6P for glycolysis and the pentose phosphate pathway (PPP). The inhibition of these pathways via glucose kinases (i.e., glucokinase and hexokinase) appears to be a strategic approach for drug discovery. Glucose kinases phosphorylate d-glucose with co-substrate ATP to yield G6P and the formed G6P enters both pathways for catabolism. The compound screen revealed five on-target confirmed inhibitors that were all from the d-GlcN series, such as compounds 1, 2, 4, 5, and 6. Four of these compounds were strong TcGlcK inhibitors (1, 2, 4, and 6) since they were found to have micromolar inhibitory constant (Ki) values around 20 μM. Three of the on-target confirmed inhibitors (1, 5, and 6) revealed notable in vitro anti-T. cruzi activity with IC50 values being less than 50 μM. Compound 1 was benzoyl glucosamine (BENZ-GlcN), a known TcGlcK inhibitor that was the starting point for the design of the compounds in this study; in addition, TcGlcK – compound 1 inhibition properties were previously determined [D’Antonio, E. L. et al. (2015) Mol. Biochem. Parasitol. 204, 64–76]. As such, compounds 5 and 6 were further evaluated biochemically, where formal Ki values were determined as well as their mode of TcGlcK inhibition. The Ki values determined for compounds 5 and 6 were 107 ± 4 μM and 15.2 ± 3.3 μM, respectively, and both of these compounds exhibited the competitive inhibition mode.