Matthew J. Wyvratt

Human β3-adrenergic receptor agonists containing 1,2,3-triazole-substituted benzenesulfonamides

Compounds containing a 1,2,3-triazole-substituted benzenesulfonamide were prepared and found to be potent and selective human beta3-adrenergic receptor agonists. The most interesting compound, trifluoromethylbenzyl analogue 12e (beta3 EC50 = 3.1 nM with >1500-fold selectivity over binding to both beta1- and beta2 receptors), stimulates lipolysis in the rhesus monkey (ED50 = 0.36 mg/kg) and is 25% orally bioavailable in the dog.

Broad spectrum antiprotozoal agents that inhibit histone deacetylase: structure-activity relationships of apicidin. Part 1.

Apicidin, a natural product recently isolated at Merck, inhibits both mammalian and protozoan histone deacetylases (HDACs). The conversion of apicidin, a nanomolar inhibitor of HDACs, into a series of side-chain analogues that display picomolar enzyme affinity is described within this structure-activity study.

Identification and initial structure-activity relationships of a novel non-peptide quinolone GnRH receptor antagonist.

Screening of the Merck sample collection for non-peptide compounds with binding affinity for the rat GnRH receptor led to the identification of the substituted quinolone (1) as a lead compound in the search for a non-peptide GnRH receptor antagonist. Substantial improvements in potency (approximately 300 fold) were achieved by addition of an alkyl amine at the 4-position, a 3,5-dimethylphenyl group at the 3-position and 6-nitro-7-chloro-substitution of the 1 H-quinolone core.

Potent, selective human β3 adrenergic receptor agonists containing a substituted indoline-5-sulfonamide pharmacophore

A series of compounds possessing an N-substituted indoline-5-sulfonamide pharmacophore was prepared and evaluated for their human beta3 adrenergic receptor agonist activity. The SAR of a wide range of urea and heterocyclic substituents is discussed. 4-Octyl thiazole compound 8c was the most potent and selective compound in the series, with 2800-fold selectivity over beta1 binding and 1400-fold selectivity over beta2 binding.

Potent antagonists of gonadotropin releasing hormone receptors derived from quinolone-6-carboxamides

SAR studies which focused upon the C-6 position of a recently described series of quinolone gonadotropin releasing hormone antagonists are reported. Synthetic access to diverse quinolone-6-carboxamides was achieved via the palladium-catalyzed amino-carbonylation reactions of iodide 4 with various amines. Amides related to 9y were especially potent, functional antagonists of rat and human GnRH receptors.

L-770,644 : A potent and selective human β3 adrenergic receptor agonist with improved oral bioavailability

L-770,644 (9c) is a potent and selective agonist of the human beta3 adrenergic receptor (EC50 = 13 nM). It shows good oral bioavailability in both dogs and rats (%F = 27), and is a full agonist for glycerolemia in the rhesus monkey (ED50 = 0.21 mg/kg). Based on its desirable in vitro and in vivo properties, L-770,644 was chosen for further preclinical evaluation.

Initial structure–activity relationship of a novel class of nonpeptidyl GnRH receptor antagonists: 2-arylindoles

A nonpeptidyl GnRH receptor antagonist (1), with a unique 2-arylindole core, was identified through the Merck in-house screening for binding affinity on the rat GnRH receptor. SAR studies directed toward the alkoxy-ethanolamine and 2-aryl groups resulted in a simpler lead structure with improved activity. This compound 50 exhibits a 60-fold improvement in binding activity over our initial lead 1.

Discovery of Potent and Selective Dipeptidyl Peptidase IV Inhibitors Derived from [beta]-Aminoamides Bearing Subsituted Triazolopiperazines

A series of beta-aminoamides bearing triazolopiperazines have been discovered as potent, selective, and orally active dipeptidyl peptidase IV (DPP-4) inhibitors by extensive structure-activity relationship (SAR) studies around the triazolopiperazine moiety. Among these, compound 34b with excellent in vitro potency (IC50 = 4.3 nM) against DPP-4, high selectivity over other enzymes, and good pharmacokinetic profiles exhibited pronounced in vivo efficacy in an oral glucose tolerance test (OGTT) in lean mice. On the basis of these properties, compound 34b has been profiled in detail. Further refinement of the triazolopiperazines resulted in the discovery of a series of extremely potent compounds with subnanomolar activity against DPP-4 (42b- 49b), that is, 4-fluorobenzyl-substituted compound 46b, which is notable for its superior potency (IC50 = 0.18 nM). X-ray crystal structure determination of compounds 34b and 46b in complex with DPP-4 enzyme revealed that (R)-stereochemistry at the 8-position of triazolopiperazines is strongly preferred over (S) with respect to DPP-4 inhibition.

Investigation of the 4-O-alkylamine substituent of non-peptide quinolone GnRH receptor antagonists

Synthesis and in vitro activity of the enantiomers of quinolone GnRH antagonist (+/-)-1 are reported. Chiral amino alcohols were prepared from the appropriate cyclic D- or L-amino acids by the Amdt-Eistert homologation followed by reduction of the resulting esters. Incorporation of these pharmacophores was achieved via a novel Mitsunobu alkylation of 4-hydroxyquinolones. The key amine pharmacophore for binding to the rat GnRH receptor was most active in the S-configuration. Ring size was not important for potency with 4, 5, 6, and 7-membered ring amines exhibiting similar potency.

Discovery of novel avermectins with unprecedented insecticidal activity

A new class of insecticidal and antiparasitic agents, 4″-amino-4′-deoxy avermectins, has been developed by chemical modification of avermectin B1. The most effective of these compounds are 1500-fold more potent than avermectin B1 (abamectin) against the beet armywormSpodoptera exigua and show similar potency against other lepidopteran larvae.