4-Aminopyridyl-Based CYP51 Inhibitors as Anti-Trypanosoma cruzi Drug Leads with Improved Pharmacokinetic Profile and in Vivo Potency
摘要:
CYP51 is a P450 enzyme involved in the biosynthesis of the sterol components of eukaryotic cell membranes. CYP51 inhibitors have been developed to treat infections caused by fungi, and more recently the protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. To specifically optimize drug candidates for T. cruzi CYP51 (TcCYP51), we explored the structure activity relationship (SAR) of a N-indolyl-oxopyridinyl-4-aminopropanyl-based scaffold originally identified in a target-based screen. This scaffold evolved via medicinal chemistry to yield orally bioavailable leads with potent anti-T. cruzi activity in vivo. Using an animal model of infection with a transgenic T. cruzi Y luc strain expressing firefly luciferase, we prioritized the biaryl and N-arylpiperazine analogues by oral bioavailability and potency. The drug target complexes for both scaffold variants were characterized by X-ray structure analysis. Optimization of both binding mode and pharmacokinetic properties of these compounds led to potent inhibitors against experimental T. cruzi infection.
The invention provides inhibitors of a sterol C14-demethylase, a new series of 4- aminopyridyl-based lead inhibitors targeting Trypanosoma cruzi CYP51 (TcCYP51) developed using structure-based drug design as well as structure -property relationship (SPR) analyses. The screening hit starting point, LP 10 (KD < 42 nM; EC50 of 0.65 μΜ), has been optimized to give the potential leads that have low nanomolar binding affinity to TcCYP51 and significant activity against T. cruzi amastigotes cultured in human myoblasts. Many of the optimized compounds have improved microsome stability, and most are selective against the T. cruzi CYP51 relative to human CYPs 1A2, 2D6 and 3A4 (<50% inhibition at 1 μΜ). A rationale for the improvement of microsome stability and selectivity of inhibitors against human metabolic CYP enzymes is presented. In addition, the binding mode of several compounds of the invention with the T. brucei CYP51 (TbCYP51) ortholog has been characterized by x-ray structure analysis. Orally active compounds and their cyclodextrin complexes have been shown to be effective against Chagas-infected mice.
4-Aminopyridyl-Based CYP51 Inhibitors as Anti-<i>Trypanosoma cruzi</i> Drug Leads with Improved Pharmacokinetic Profile and in Vivo Potency
作者:Claudia M. Calvet、Debora F. Vieira、Jun Yong Choi、Danielle Kellar、Michael D. Cameron、Jair Lage Siqueira-Neto、Jiri Gut、Jonathan B. Johnston、Li Lin、Susan Khan、James H. McKerrow、William R. Roush、Larissa M. Podust
DOI:10.1021/jm500448u
日期:2014.8.28
CYP51 is a P450 enzyme involved in the biosynthesis of the sterol components of eukaryotic cell membranes. CYP51 inhibitors have been developed to treat infections caused by fungi, and more recently the protozoan parasite Trypanosoma cruzi, the causative agent of Chagas disease. To specifically optimize drug candidates for T. cruzi CYP51 (TcCYP51), we explored the structure activity relationship (SAR) of a N-indolyl-oxopyridinyl-4-aminopropanyl-based scaffold originally identified in a target-based screen. This scaffold evolved via medicinal chemistry to yield orally bioavailable leads with potent anti-T. cruzi activity in vivo. Using an animal model of infection with a transgenic T. cruzi Y luc strain expressing firefly luciferase, we prioritized the biaryl and N-arylpiperazine analogues by oral bioavailability and potency. The drug target complexes for both scaffold variants were characterized by X-ray structure analysis. Optimization of both binding mode and pharmacokinetic properties of these compounds led to potent inhibitors against experimental T. cruzi infection.
<i>R</i>-Configuration of 4-Aminopyridyl-Based Inhibitors of CYP51 Confers Superior Efficacy Against <i>Trypanosoma cruzi</i>
作者:Jun Yong Choi、Claudia M. Calvet、Debora F. Vieira、Shamila S. Gunatilleke、Michael D. Cameron、James H. McKerrow、Larissa M. Podust、William R. Roush
DOI:10.1021/ml500010m
日期:2014.4.10
Sterol 14 alpha-demethylase (CYP51) is an important therapeutic target for fungal and parasitic infections due to its key role in the biosynthesis of ergosterol, an essential component of the cell membranes of these pathogenic organisms. We report the development of potent and selective D-tryptophan-derived inhibitors of T. cruzi CYP51. Structural information obtained from the cocrystal structure of CYP51 and (R)-2, which is >1000-fold more potent than its enantiomer (S)-1, was used to guide design of additional analogues. The in vitro efficacy data presented here for (R)-2 (R)-8, together with preliminary in vitro pharmacokinetic data suggest that this new CYP51 inhibitor scaffold series has potential to deliver drug candidates for treatment of T. cruzi infections.