Diaryl dihydropyrazole-3-carboxamides with significant in vivo antiobesity activity related to CB1 receptor antagonism: synthesis, biological evaluation, and molecular modeling in the homology model

J Med Chem. 2007 Nov 29;50(24):5951-66. doi: 10.1021/jm061490u. Epub 2007 Nov 3.

Abstract

A number of analogues of diaryl dihydropyrazole-3-carboxamides have been synthesized. Their activities were evaluated for appetite suppression and body weight reduction in animal models. Depending on the chemical modification of the selected dihydropyrazole scaffold, the lead compounds--the bisulfate salt of (+/-)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid morpholin-4-ylamide 26 and the bisulfate salt of (-)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid morpholin-4-ylamide 30--showed significant body weight reduction in vivo, which is attributed to their CB1 antagonistic activity and exhibited a favorable pharmacokinetic profile. The molecular modeling studies also showed interactions of two isomers of (+/-)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid morpholin-4-ylamide 9 with CB1 receptor in the homology model similar to those of N-piperidino-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-3-pyrazole-carboxamide (rimonabant) 1 and 4S-(-)-3-(4-chlorophenyl)-N-methyl-N'-[(4-chlorophenyl)-sulfonyl]-4-phenyl-4,5-dihydro-1H-pyrazole-1-carboxamidine (SLV-319) 2.

MeSH terms

  • Amides / chemical synthesis*
  • Amides / pharmacokinetics
  • Amides / pharmacology
  • Animals
  • Anti-Obesity Agents / chemical synthesis*
  • Anti-Obesity Agents / pharmacokinetics
  • Anti-Obesity Agents / pharmacology
  • Appetite Depressants / chemical synthesis
  • Appetite Depressants / pharmacokinetics
  • Appetite Depressants / pharmacology
  • Body Weight / drug effects
  • Female
  • Models, Molecular
  • Morpholines / chemical synthesis
  • Morpholines / pharmacokinetics
  • Morpholines / pharmacology
  • Piperidines / chemistry
  • Pyrazoles / chemical synthesis*
  • Pyrazoles / chemistry
  • Pyrazoles / pharmacokinetics
  • Pyrazoles / pharmacology
  • Rats
  • Rats, Zucker
  • Receptor, Cannabinoid, CB1 / antagonists & inhibitors
  • Rimonabant
  • Stereoisomerism
  • Structure-Activity Relationship
  • Sulfonamides / chemistry

Substances

  • 3-(4-chlorophenyl)-N-methyl-N'-((4-chlorophenyl)sulfonyl)-4-phenyl-4,5-dihydro-1H-pyrazole-1-carboxamidine
  • Amides
  • Anti-Obesity Agents
  • Appetite Depressants
  • Morpholines
  • Piperidines
  • Pyrazoles
  • Receptor, Cannabinoid, CB1
  • Sulfonamides
  • Rimonabant