Synthesis and structure-activity relationships of indazole arylsulfonamides as allosteric CC-chemokine receptor 4 (CCR4) antagonists

J Med Chem. 2013 Mar 14;56(5):1946-60. doi: 10.1021/jm301572h. Epub 2013 Feb 27.

Abstract

A series of indazole arylsulfonamides were synthesized and examined as human CCR4 antagonists. Methoxy- or hydroxyl-containing groups were the more potent indazole C4 substituents. Only small groups were tolerated at C5, C6, or C7, with the C6 analogues being preferred. The most potent N3-substituent was 5-chlorothiophene-2-sulfonamide. N1 meta-substituted benzyl groups possessing an α-amino-3-[(methylamino)acyl]-group were the most potent N1-substituents. Strongly basic amino groups had low oral absorption in vivo. Less basic analogues, such as morpholines, had good oral absorption; however, they also had high clearance. The most potent compound with high absorption in two species was analogue 6 (GSK2239633A), which was selected for further development. Aryl sulfonamide antagonists bind to CCR4 at an intracellular allosteric site denoted site II. X-ray diffraction studies on two indazole sulfonamide fragments suggested the presence of an important intramolecular interaction in the active conformation.

MeSH terms

  • Animals
  • Dogs
  • Humans
  • Indazoles / chemical synthesis
  • Indazoles / pharmacokinetics
  • Indazoles / pharmacology*
  • Male
  • Rats
  • Receptors, CCR4 / antagonists & inhibitors*
  • Structure-Activity Relationship
  • Sulfonamides / chemical synthesis*
  • Sulfonamides / pharmacokinetics
  • Sulfonamides / pharmacology*

Substances

  • Indazoles
  • N-((3-((3-(((5-chloro-2-thienyl)sulfonyl)amino)-4-(methyloxy)-1H-indazol-1-yl)methyl)phenyl)methyl)-2-hydroxy-2-methylpropanamide
  • Receptors, CCR4
  • Sulfonamides