Quinazolinone derivatives as orally available ghrelin receptor antagonists for the treatment of diabetes and obesity

J Med Chem. 2007 Oct 18;50(21):5202-16. doi: 10.1021/jm070071+. Epub 2007 Sep 21.


The peptide hormone ghrelin is the endogenous ligand for the type 1a growth hormone secretagogue receptor (GHS-R1a) and the only currently known circulating appetite stimulant. GHS-R1a antagonism has therefore been proposed as a potential approach for obesity treatment. More recently, ghrelin has been recognized to also play a role in controlling glucose-induced insulin secretion, which suggests another possible benefit for a GHS-R1a antagonist, namely, the role as an insulin secretagogue with potential value for diabetes treatment. In our laboratories, piperidine-substituted quinazolinone derivatives were identified as a new class of small-molecule GHS-R1a antagonists. Starting from an agonist with poor oral bioavailability, optimization led to potent, selective, and orally bioavailable antagonists. In vivo efficacy evaluation of selected compounds revealed suppression of food intake and body weight reduction as well as glucose-lowering effects mediated by glucose-dependent insulin secretion.

MeSH terms

  • Administration, Oral
  • Animals
  • Binding, Competitive
  • Blood Glucose / analysis
  • Cell Line
  • Diabetes Mellitus / drug therapy*
  • Eating / drug effects
  • Glucose Tolerance Test
  • Humans
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Obesity / drug therapy*
  • Quinazolinones / chemical synthesis*
  • Quinazolinones / chemistry
  • Quinazolinones / pharmacology
  • Radioligand Assay
  • Rats
  • Rats, Wistar
  • Receptors, Ghrelin / antagonists & inhibitors*
  • Stereoisomerism
  • Structure-Activity Relationship
  • Weight Loss / drug effects


  • 6-(4-fluorophenoxy)-3-((1-isopropylpiperidin-3-yl)methyl)-2-methylquinazolin-4(3H)-one
  • 6-(4-fluorophenyl)-2-isopropyl-3-((1-isopropylpiperidin-3-yl)methyl)quinazolin-4(3H)-one
  • Blood Glucose
  • Quinazolinones
  • Receptors, Ghrelin