Structure-affinity relationships of a unique nicotinic ligand: N(1)-dimethyl-N(4)-phenylpiperazinium iodide (DMPP)

J Med Chem. 2001 Nov 8;44(23):3946-55. doi: 10.1021/jm010901y.

Abstract

DMPP is a well-known nicotinic agonist that does not fit any proposed pharmacophore for nicotinic binding and represents a unique ligand among the hundreds of nicotinic agonists studied in the past decades. A systematic modulation of the chemical structure of DMPP, aimed to establish its structure-affinity relationships, is reported. The research has allowed to identify molecules such as 11c, 13c, 14c, and 28c, with affinities for alpha(4)beta(2) receptors in the low nanomolar range, some 2 orders of magnitude lower than the lead compound. The agonistic properties of the most interesting compounds have been assessed by measuring their analgesic activity on mice (hot-plate test). Another result of the research was the identification of DMPP analogues, such as 3a (K(i) = 90 nM) and 14b (K(i) = 180 nM), that maintain affinity for the central nicotinic receptor when the ammonium function is changed into an aminic one and are therefore possible leads for drug development in neurodegenerative diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analgesics / chemical synthesis
  • Analgesics / chemistry
  • Analgesics / pharmacology
  • Animals
  • Cerebral Cortex / metabolism
  • Dimethylphenylpiperazinium Iodide / analogs & derivatives*
  • Dimethylphenylpiperazinium Iodide / chemical synthesis*
  • Dimethylphenylpiperazinium Iodide / chemistry
  • Dimethylphenylpiperazinium Iodide / pharmacology
  • In Vitro Techniques
  • Ligands
  • Male
  • Mice
  • Nicotinic Agonists / chemical synthesis*
  • Nicotinic Agonists / chemistry
  • Nicotinic Agonists / pharmacology
  • Pain Measurement
  • Piperidines / chemical synthesis*
  • Piperidines / chemistry
  • Piperidines / pharmacology
  • Pyridines / chemical synthesis*
  • Pyridines / chemistry
  • Pyridines / pharmacology
  • Radioligand Assay
  • Rats
  • Rats, Wistar
  • Receptors, Nicotinic / metabolism*
  • Structure-Activity Relationship

Substances

  • Analgesics
  • Ligands
  • Nicotinic Agonists
  • Piperidines
  • Pyridines
  • Receptors, Nicotinic
  • Dimethylphenylpiperazinium Iodide