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Abstract Within the realm of drug discovery, high‐throughput experimentation techniques enable the rapid optimization of reactions and expedited generation of drug compound libraries for biological and pharmacokinetic evaluation. Herein we report the development of a segmented flow mass spectrometry‐based platform to enable the rapid exploration of photoredox reactions for early‐stage drug discovery. Specifically, microwell plate‐based photochemical reaction screens were reformatted to segmented flow format to enable delivery to nanoelectrospray ionization‐mass spectrometry analysis. This approach was demonstrated for the late‐stage modification of complex drug scaffolds, as well as the subsequent structure–activity relationship evaluation of synthesized analogs. This technology is anticipated to expand the robust capabilities of photoredox catalysis in drug discovery by enabling high‐throughput library diversification.
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Late‐Stage Functionalization and Characterization of Drugs by High‐Throughput Desorption Electrospray Ionization Mass Spectrometry
Abstract Late‐stage functionalization (LSF) of drug molecules is an approach to generate modified molecules that retain functional groups present in the active drugs. Here, we report a study that seeks to characterize the potential value of high‐throughput desorption electrospray ionization mass spectrometry (HT DESI‐MS) for small‐scale rapid LSF. In conventional route screening, HT‐based DESI‐MS provides contactless, rapid analysis, reliable and reproducible data, minimal sample requirement, and exceptional tolerance to high salt concentrations. Ezetimibe (E), an established hypertension drug, is targeted for modification by LSF. C−H alkenylation and azo‐click reactions are utilized to explore this approach to synthesis and analytical characterization. The effect of choice of reactant, stoichiometry, catalyst, and solvent are studied for both reactions using high throughput DESI‐MS experiments. Optimum conditions for the formation of LSF products are established with identification by tandem mass spectrometry (MS/MS).
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- Award ID(s):
- 1905087
- PAR ID:
- 10361980
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPlusChem
- Volume:
- 87
- Issue:
- 1
- ISSN:
- 2192-6506
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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