Design, Synthesis, and Biological Evaluation of 4-Quinoline Carboxylic Acids as Inhibitors of Dihydroorotate Dehydrogenase

J Med Chem. 2018 Jun 28;61(12):5162-5186. doi: 10.1021/acs.jmedchem.7b01862. Epub 2018 May 14.

Abstract

We pursued a structure-guided approach toward the development of improved dihydroorotate dehydrogenase (DHODH) inhibitors with the goal of forming new interactions between DHODH and the brequinar class of inhibitors. Two potential residues, T63 and Y356, suitable for novel H-bonding interactions, were identified in the brequinar-binding pocket. Analogues were designed to maintain the essential pharmacophore and form new electrostatic interactions through strategically positioned H-bond accepting groups. This effort led to the discovery of potent quinoline-based analogues 41 (DHODH IC50 = 9.71 ± 1.4 nM) and 43 (DHODH IC50 = 26.2 ± 1.8 nM). A cocrystal structure between 43 and DHODH depicts a novel water mediated H-bond interaction with T63. Additional optimization led to the 1,7-naphthyridine 46 (DHODH IC50 = 28.3 ± 3.3 nM) that forms a novel H-bond with Y356. Importantly, compound 41 possesses significant oral bioavailability ( F = 56%) and an elimination t1/2 = 2.78 h (PO dosing). In conclusion, the data supports further preclinical studies of our lead compounds toward selection of a candidate for early-stage clinical development.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Administration, Oral
  • Animals
  • Biphenyl Compounds / chemistry
  • Crystallography, X-Ray
  • Dihydroorotate Dehydrogenase
  • Drug Design
  • Drug Evaluation, Preclinical / methods
  • Enzyme Inhibitors / chemical synthesis
  • Enzyme Inhibitors / chemistry*
  • Enzyme Inhibitors / pharmacology*
  • Female
  • HCT116 Cells
  • Half-Life
  • Humans
  • Hydrogen Bonding
  • Mice, Inbred Strains
  • Oxidoreductases Acting on CH-CH Group Donors / antagonists & inhibitors*
  • Oxidoreductases Acting on CH-CH Group Donors / chemistry*
  • Oxidoreductases Acting on CH-CH Group Donors / metabolism
  • Pyridines / chemistry
  • Pyrimidines / chemistry
  • Quinolines / chemistry*
  • Solubility
  • Structure-Activity Relationship
  • Thermodynamics

Substances

  • Biphenyl Compounds
  • Dihydroorotate Dehydrogenase
  • Enzyme Inhibitors
  • Pyridines
  • Pyrimidines
  • Quinolines
  • quinoline-4-carboxylic acid
  • brequinar
  • Oxidoreductases Acting on CH-CH Group Donors
  • pyrimidine