ABSTRACT
This letter describes the discovery and SAR optimization of tetrazoyl tetrahydroquinoline derivatives as potent CETP inhibitors. Compound 6m exhibited robust HDL-c increase in hCETP/hApoA1 double transgenic model and favorable pharmacokinetic properties.
Subject(s)
Cholesterol Ester Transfer Proteins/antagonists & inhibitors , Drug Design , Hypolipidemic Agents/chemical synthesis , Quinolines/chemistry , Tetrazoles/chemical synthesis , Animals , Apolipoprotein A-I/genetics , Apolipoprotein A-I/metabolism , Cholesterol Ester Transfer Proteins/genetics , Cholesterol Ester Transfer Proteins/metabolism , Cholesterol, HDL/drug effects , Cholesterol, HDL/metabolism , Dogs , Female , Hypolipidemic Agents/chemistry , Hypolipidemic Agents/pharmacokinetics , Injections, Intravenous , Male , Mice , Mice, Transgenic , Quinolines/chemical synthesis , Quinolines/pharmacokinetics , Rats , Rats, Sprague-Dawley , Structure-Activity Relationship , Tetrazoles/chemistry , Tetrazoles/pharmacokineticsABSTRACT
2-Methylalanyl-N-{1-[(1R)-1-(4-fluorophenyl)-1-methyl-2-oxo-2-pyrrolidin-1-ylethyl]-1H-imidazol-4-yl}-5-phenyl-D-norvalinamide (LY654322) was rapidly cleared in rats and dogs by renal excretion of parent and metabolism (oxidative and hydrolytic). Among the metabolites identified in the urine of rats and dogs was M25, which was structurally unusual. Indeed, the characterization of M25 and investigation into its disposition relied on the convergence of diverse analytical methodologies. M25 eluted after the parent on reverse-phase chromatography with an MH(+) at m/z 598 (parent + 35 Da). Given its increased lipophilicity and its mass difference compared with the parent, it was evident that M25 was not a phase 2 conjugate. Subsequent liquid chromatography with multiple-stage tandem mass spectrometry and accurate mass experiments identified the structure of M25 as having two replicates of the 1-(4-fluorophenyl)-1-methyl-2-oxo-2-pyrrolidinyl substructure flanking a central aromatic core of composition C(7)H(3)N(5) that was refractory to fragmentation. Compared with the UV spectrum of the parent (λ(max) = 213 nm), M25 displayed a bathochromic shift (λ(max) = 311 nm), which substantiated extensive conjugation within the central core. Subsequent NMR analysis of M25 isolated from dog urine coupled with molecular modeling revealed the structure to be consistent with a diimidazopyridine core with two symmetrically substituted 1-(4-fluorophenyl)-1-methyl-2-oxo-2-pyrrolidinyl moieties. Using a structural analog with a chromophore similar to M25, LC-UV was used to quantitate M25 and determine its urinary disposition. The formation of M25 appears consistent with hydrolysis of LY654322 to an aminoimidazole, dimerization of the latter with the loss of NH(3), C-formylation, and subsequent ring closure and aromatization with loss of H(2)O.
Subject(s)
Dipeptides/chemistry , Dipeptides/metabolism , Heterocyclic Compounds, 3-Ring/analysis , Heterocyclic Compounds, 3-Ring/chemistry , Imidazoles/chemistry , Imidazoles/metabolism , Pyridines/analysis , Pyridines/chemistry , Receptors, Ghrelin/agonists , Animals , Dipeptides/blood , Dipeptides/pharmacokinetics , Dipeptides/pharmacology , Dogs , Female , Human Growth Hormone/metabolism , Imidazoles/blood , Imidazoles/pharmacokinetics , Imidazoles/pharmacology , Male , Rats , Rats, Inbred F344 , Receptors, Ghrelin/metabolismABSTRACT
The synthesis and biological evaluation of a series of oxindole beta(3) adrenergic receptor agonists is described. A modulation of rat atrial tachycardia was observed with substitution at the 3-position of the oxindole moiety.
Subject(s)
Adrenergic beta-3 Receptor Agonists , Adrenergic beta-Agonists/chemical synthesis , Adrenergic beta-Agonists/pharmacology , Indoles/chemical synthesis , Indoles/pharmacology , Tachycardia/drug therapy , Adrenergic beta-Agonists/chemistry , Animals , CHO Cells , Cricetinae , Cricetulus , Disease Models, Animal , Drug Evaluation, Preclinical , Humans , Indoles/chemistry , Molecular Structure , Oxindoles , Rats , Rats, Long-Evans , Receptors, Adrenergic, beta-3/biosynthesis , Receptors, Adrenergic, beta-3/geneticsABSTRACT
The synthesis and biological evaluation of a series of benzimidazolone beta(3) adrenergic receptor agonists are described. A trend toward the reduction of rat atrial tachycardia upon increasing steric bulk at the 3-position of the benzimidazolone moiety was observed.
Subject(s)
Adrenergic beta-3 Receptor Antagonists , Adrenergic beta-Agonists/pharmacology , Benzimidazoles/pharmacology , Adrenergic beta-Agonists/chemistry , Benzimidazoles/chemistry , HumansABSTRACT
The microsomal metabolism of 7-ethoxycoumarin (7-EC) was investigated using liquid chromatography (LC)-NMR and liquid chromatography-mass spectrometry (LC-MS) to characterize the coupling of oxidative-conjugative metabolism events. Within microsomes, cytochromes P450 (P450s) and UDP-glucuronosyltransferases (UGTs) are spatially disparate, each having surface and luminal localization, respectively. To optimize cofactor and substrate transit to UGT without compromising P450 activity, the pore-forming peptide alamethicin was used for microsomal perforation. Aqueous extracts of microsomal incubations containing NADPH and UDP-glucuronic acid were injected for LC-NMR and LC-MS analysis. The analytical complementarity of LC-NMR and LC-MS permitted the identification of four metabolites (M1 to M4). The metabolites M1 and M2 are novel microsomal metabolites for 7-EC, consistent with 3-hydroxylation and subsequent glucuronidation, respectively. Metabolites M3 and M4 were 7-hydroxycoumarin (7-HC) and 7-HC glucuronide, respectively. Viewed collectively, these results illustrate the utility of alamethicin in the examination of coupled oxidative-conjugative metabolism and the synergy of LC-NMR and LC-MS in metabolite identification.