Publications by authors named "Pearly Shuyi Ng"

3 Publications

  • Page 1 of 1

Discovery of a Novel Mycobacterial F-ATP Synthase Inhibitor and its Potency in Combination with Diarylquinolines.

Angew Chem Int Ed Engl 2020 08 26;59(32):13295-13304. Epub 2020 May 26.

School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.

The F F -ATP synthase is required for growth and viability of Mycobacterium tuberculosis and is a validated clinical target. A mycobacterium-specific loop of the enzyme's rotary γ subunit plays a role in the coupling of ATP synthesis within the enzyme complex. We report the discovery of a novel antimycobacterial, termed GaMF1, that targets this γ subunit loop. Biochemical and NMR studies show that GaMF1 inhibits ATP synthase activity by binding to the loop. GaMF1 is bactericidal and is active against multidrug- as well as bedaquiline-resistant strains. Chemistry efforts on the scaffold revealed a dynamic structure activity relationship and delivered analogues with nanomolar potencies. Combining GaMF1 with bedaquiline or novel diarylquinoline analogues showed potentiation without inducing genotoxicity or phenotypic changes in a human embryonic stem cell reporter assay. These results suggest that GaMF1 presents an attractive lead for the discovery of a novel class of anti-tuberculosis F-ATP synthase inhibitors.
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http://dx.doi.org/10.1002/anie.202002546DOI Listing
August 2020

Structure activity relationships of 4-hydroxy-2-pyridones: A novel class of antituberculosis agents.

Eur J Med Chem 2015 Dec 14;106:144-56. Epub 2015 Oct 14.

Novartis Institute for Tropical Diseases, 10 Biopolis Road, #05-01 Chromos, Singapore 138670, Singapore. Electronic address:

Pyridone 1 was identified from a high-throughput cell-based phenotypic screen against Mycobacterium tuberculosis (Mtb) including multi-drug resistant tuberculosis (MDR-TB) as a novel anti-TB agent and subsequently optimized series using cell-based Mtb assay. Preliminary structure activity relationship on the isobutyl group with higher cycloalkyl groups at 6-position of pyridone ring has enabled us to significant improvement of potency against Mtb. The lead compound 30j, a dimethylcyclohexyl group on the 6-position of the pyridone, displayed desirable in vitro potency against both drug sensitive and multi-drug resistant TB clinical isolates. In addition, 30j displayed favorable oral pharmacokinetic properties and demonstrated in vivo efficacy in mouse model. These results emphasize the importance of 4-hydroxy-2-pyridones as a new chemotype and further optimization of properties to treat MDR-TB.
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http://dx.doi.org/10.1016/j.ejmech.2015.10.008DOI Listing
December 2015

Direct inhibitors of InhA are active against Mycobacterium tuberculosis.

Sci Transl Med 2015 Jan;7(269):269ra3

Novartis Institute for Tropical Diseases, 138670 Singapore, Singapore. Yong Loo Lin School of Medicine, National University of Singapore, 119228 Singapore, Singapore.

New chemotherapeutic agents are urgently required to combat the global spread of multidrug-resistant tuberculosis (MDR-TB). The mycobacterial enoyl reductase InhA is one of the few clinically validated targets in tuberculosis drug discovery. We report the identification of a new class of direct InhA inhibitors, the 4-hydroxy-2-pyridones, using phenotypic high-throughput whole-cell screening. This class of orally active compounds showed potent bactericidal activity against common isoniazid-resistant TB clinical isolates. Biophysical studies revealed that 4-hydroxy-2-pyridones bound specifically to InhA in an NADH (reduced form of nicotinamide adenine dinucleotide)-dependent manner and blocked the enoyl substrate-binding pocket. The lead compound NITD-916 directly blocked InhA in a dose-dependent manner and showed in vivo efficacy in acute and established mouse models of Mycobacterium tuberculosis infection. Collectively, our structural and biochemical data open up new avenues for rational structure-guided optimization of the 4-hydroxy-2-pyridone class of compounds for the treatment of MDR-TB.
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http://dx.doi.org/10.1126/scitranslmed.3010597DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4383039PMC
January 2015
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