ABSTRACT
The optimization of the distance between two key pharmacophore features within our first hit compounds 1a and 2a led to the identification of a new class of potent non-peptidic antagonists for the MCH-R1, based around 4-amino-2-cyclohexylaminoquinazolines. In particular, ATC0065 (2c), N2-[cis-4-([2-[4-Bromo-2-(trifluoromethoxy)phenyl]ethyl]amino)cyclohexyl]-N4,N4-dimethylquinazoline-2,4-diamine dihydrochloride, bound with high affinity to the MCH-R1 (IC50 value of 16 nM) and showed good metabolic stability in liver microsomes from human and rat.
Subject(s)
Quinazolines/chemistry , Quinazolines/pharmacology , Receptors, Somatostatin/antagonists & inhibitors , Receptors, Somatostatin/chemistry , Animals , Humans , Lethal Dose 50 , Microsomes/metabolism , Molecular Structure , RatsABSTRACT
The optimization of a series of 4-(dimethylamino)quinazoline antagonists of the melanin-concentrating hormone receptor 1 (MCH-R1) is described. The combination of the elaboration of both the linker portion and the terminal phenyl ring provided N-(cis-4-{[4-(dimethylamino)quinazolin-2-yl]amino}cyclohexyl)-3,4-difluorobenzamide hydrochloride 28 (ATC0175), which showed excellent antagonist activity at the MCH-R1 (IC50 = 3.4 nM) as well as good selectivity over the Y5 and the alpha2A receptors.
Subject(s)
Quinazolines/chemical synthesis , Receptors, Somatostatin/antagonists & inhibitors , Humans , Inhibitory Concentration 50 , Quinazolines/chemistry , Quinazolines/pharmacology , Radioligand Assay , Structure-Activity Relationship , Substrate SpecificityABSTRACT
A series of 4-(dimethylamino)quinazoline based antagonists of the melanin-concentrating hormone receptor 1 (MCH-R1) is described. This series was derived from a lead compound, AR129330, identified by HTS of a GPCR-directed library using a functional assay with a constitutively activated (CART) form of the receptor. The preliminary optimization resulted in the identification of compounds 20, 21, and 23.
Subject(s)
Quinazolines/chemistry , Quinazolines/pharmacology , Receptors, Pituitary Hormone/antagonists & inhibitors , Cell Line , Humans , Structure-Activity RelationshipABSTRACT
Melanin-concentrating hormone (MCH) is a cyclic peptide produced in the lateral hypothalamus. It has been implicated in a number of physiological processes including feeding behavior, energy balance, and the regulation of emotional states. Here, we report in vitro and in vivo profiles of ATC0065 [N(2)-[cis-4-({2-[4-bromo-2-(trifluoromethoxy)phenyl]ethyl}amino)cyclohexyl]-N(4), N(4)-dimethylquinazoline-2,4-diamine dihydrochloride] and ATC0175 [N-(cis-4-{[4-(dimethylamino)quinazolin-2-yl]amino}cyclohexyl)-3,4-difluorobenzamide hydrochloride], newly synthesized MCH receptor 1 (MCHR1) antagonists. Both ATC0065 and ATC0175 had high affinities for human MCHR1 with IC(50) values of 15.7 +/- 1.95 and 7.23 +/- 0.59 nM, respectively. Both ATC0065 (IC(50) = 21.4 +/- 1.57 nM) and ATC0175 (IC(50) = 13.5 +/- 0.78 nM) showed potent antagonist activities at MCHR1, as assessed by MCH-increased guanosine 5'-O-(3-[(35)S]thio)phosphate ([(35)S]GTPgammaS) binding to human MCHR1. Oral administration of ATC0065 (3-30 mg/kg) or ATC0175 (1-10 mg/kg) significantly reduced immobility time in the forced swimming test in rats, indicating antidepressant-like effects. Both ATC0065 and ATC0175 significantly reversed swim stress-induced anxiety in the elevated plus-maze test in rats and stress-induced hyperthermia in mice. ATC0175 significantly increased social interaction between unfamiliar rats and reduced separation-induced vocalizations in guinea pig pups, indicating anxiolytic potential. In contrast, ATC0065 and ATC0175 did not affect spontaneous locomotor activity or rotarod performance in rats. These findings indicate that ATC0065 and ATC0175 are potent and orally active MCHR1 antagonists with anxiolytic and antidepressant activity in rodents.
Subject(s)
Anti-Anxiety Agents/administration & dosage , Antidepressive Agents/administration & dosage , Cyclohexylamines/administration & dosage , Quinazolines/administration & dosage , Receptors, Somatostatin/antagonists & inhibitors , Administration, Oral , Animals , Anti-Anxiety Agents/chemistry , Antidepressive Agents/chemistry , CHO Cells , Cricetinae , Cyclohexylamines/chemistry , Dose-Response Relationship, Drug , Female , Humans , Male , Mice , Mice, Inbred ICR , Pregnancy , Protein Binding/drug effects , Protein Binding/physiology , Quinazolines/chemistry , Rats , Rats, Sprague-Dawley , Receptors, Somatostatin/metabolism , Stress, Physiological/drug therapy , Stress, Physiological/metabolismABSTRACT
[reaction: see text]. The zirconium-mediated intramolecular ester transfer reaction of N-alkenyl carbamate derivatives proceeded to give alpha-substituted gamma-aminobutyric acid (GABA) derivatives in good to excellent yields. Quenching experiments of the reaction mixture with iodine or O2 indicated the presence of a cyclopropane intermediate. The resulting iodide was converted to 2-substituted pyrrolidine-3-carboxylate and/or alpha-alkylidene-gamma-aminobutyric acid derivatives in a stereospecific manner.
