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Title: Tuning the metabolic stability of visual cycle modulators through modification of an RPE65 recognition motif.
In the eye, the isomerization of all-trans-retinal to 11-cis-retinal is accomplished by a metabolic pathway termed the visual cycle that is critical for vision. RPE65 is the essential trans–cis isomerase of this pathway. Emixustat, a retinoid-mimetic RPE65 inhibitor, was developed as a therapeutic visual cycle modulator and used for the treatment of retinopathies. However, pharmacokinetic liabilities limit its further development including: (1) metabolic deamination of the γ-amino-α-aryl alcohol, which mediates targeted RPE65 inhibition, and (2) unwanted long-lasting RPE65 inhibition. We sought to address these issues by more broadly defining the structure–activity relationships of the RPE65 recognition motif via the synthesis of a family of novel derivatives, which were tested in vitro and in vivo for RPE65 inhibition. We identified a potent secondary amine derivative with resistance to deamination and preserved RPE65 inhibitory activity. Our data provide insights into activity-preserving modifications of the emixustat molecule that can be employed to tune its pharmacological properties.  more » « less
Award ID(s):
1904530
NSF-PAR ID:
10435793
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Journal of medicinal chemistry
Volume:
66
Issue:
12
ISSN:
0022-2623
Page Range / eLocation ID:
8140−8158
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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