Synthesis and structure-activity relationships of novel arylpiperazines as potent antagonists of α1-adrenoceptor

Eur J Med Chem. 2016 Oct 21:122:601-610. doi: 10.1016/j.ejmech.2016.06.052. Epub 2016 Jun 30.

Abstract

Arylpiperazines 2-11 were synthesized, and their biological profiles at α1-adrenergic receptors (α1-ARs) assessed by binding assays in CHO cells expressing human cloned subtypes and by functional experiments in isolated rat vas deferens (α1A), spleen (α1B), and aorta (α1D). Modifications at the 1,3-benzodioxole and phenyl phamacophoric units resulted in the identification of a number of potent compounds (moderately selective with respect to the α1b-AR), in binding experiments. Notably, compound 7 (LDT451) showed a subnanomolar pKi of 9.41 towards α1a-AR. An encouragingly lower α1B-potency was a general trend for all the series of compounds, which showed α1A/D over α1B selectivity in functional assays. If adequately optimized, such peculiar selectivity could have relevance for a potential LUTS/BPH therapeutic application.

Keywords: Adrenergic receptors subtypes; Arylpiperazines; BPH; α(1)-Adrenergic antagonists.

MeSH terms

  • Adrenergic alpha-1 Receptor Antagonists / chemical synthesis*
  • Adrenergic alpha-1 Receptor Antagonists / chemistry
  • Adrenergic alpha-1 Receptor Antagonists / metabolism
  • Adrenergic alpha-1 Receptor Antagonists / pharmacology*
  • Animals
  • CHO Cells
  • Cell Line, Tumor
  • Chemistry Techniques, Synthetic
  • Cloning, Molecular
  • Cricetinae
  • Cricetulus
  • Drug Design*
  • Humans
  • Male
  • Molecular Docking Simulation
  • Muscle, Smooth, Vascular / cytology
  • Muscle, Smooth, Vascular / drug effects
  • Piperazines / chemical synthesis*
  • Piperazines / chemistry
  • Piperazines / metabolism
  • Piperazines / pharmacology*
  • Protein Conformation
  • Rats
  • Receptors, Adrenergic, alpha-1 / chemistry
  • Receptors, Adrenergic, alpha-1 / genetics
  • Receptors, Adrenergic, alpha-1 / metabolism*
  • Signal Transduction / drug effects
  • Structure-Activity Relationship

Substances

  • Adrenergic alpha-1 Receptor Antagonists
  • Piperazines
  • Receptors, Adrenergic, alpha-1