RESUMO
Attenuation of fructose metabolism by the inhibition of ketohexokinase (KHK; fructokinase) should reduce body weight, free fatty acids, and triglycerides, thereby offering a novel approach to treat diabetes and obesity in response to modern diets. We have identified potent, selective inhibitors of human hepatic KHK within a series of pyrimidinopyrimidines (1). For example, 8, 38, and 47 exhibited KHK IC50 values of 12, 7, and 8 nM, respectively, and also showed potent cellular KHK inhibition (IC50 < 500 nM), which relates to their intrinsic potency vs KHK and their ability to penetrate cells. X-ray cocrystal structures of KHK complexes of 3, 8, and 47 revealed the important interactions within the enzyme's adenosine 5'-triphosphate (ATP)-binding pocket.
RESUMO
A new aspartic protease inhibitory chemotype bearing a 2-amino-3,4-dihydroquinazoline ring was identified by high-throughput screening for the inhibition of BACE-1. X-ray crystallography revealed that the exocyclic amino group participated in a hydrogen bonding array with the two catalytic aspartic acids of BACE-1 (Asp(32), Asp(228)). BACE-1 inhibitory potency was increased (0.9 microM to 11 nM K(i)) by substitution into the unoccupied S(1)' pocket.
Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Ácido Aspártico Endopeptidases/antagonistas & inibidores , Modelos Moleculares , Quinazolinas/síntese química , Secretases da Proteína Precursora do Amiloide/química , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/sangue , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Ácido Aspártico Endopeptidases/química , Células CHO , Células CACO-2 , Permeabilidade da Membrana Celular , Cricetinae , Cricetulus , Cristalografia por Raios X , Humanos , Ligação de Hidrogênio , Conformação Molecular , Mutação , Oligopeptídeos/química , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/metabolismo , Quinazolinas/química , Quinazolinas/farmacologia , Ratos , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
A series of N-biarylalkyl-1-phenyl-1,3,8-triazaspiro[4.5]decan-4-ones were prepared and evaluated for biological activity at opioid (mu, delta, kappa) and opioid receptor like-1 (ORL-1) G-protein coupled receptors. Substitution on the biaryl moiety produced enhanced affinity for the mu-opioid receptor.
Assuntos
Receptores Opioides/efeitos dos fármacos , Espiperona/análogos & derivados , Espiperona/farmacologia , Animais , Sítios de Ligação , Células CHO , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Cricetinae , Humanos , Estrutura Molecular , Espiperona/química , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
The reaction of molecular bromine (Br2) with arylthioureas is known to produce 2-aminobenzothiazoles (Hugerschoff reaction). We show here that benzyltrimethylammonium tribromide (1, PhCH2NMe3Br3), a stable, crystalline organic ammonium tribromide (OATB), can be readily utilized as an alternative electrophilic bromine source. It is easier to control the stoichiometry of addition with an OATB, which minimizes aromatic bromination caused by excess reagent. We have developed a direct procedure from isothiocyanates and amines using tetrabutylammonium thiocyanate (Bu4NSCN) and PhCH2NMe3Br3 to afford functionalized 2-aminobenzothiazoles.
RESUMO
5-ethoxymethyl-7-fluoro-3-oxo-1,2,3,5-tetrahydrobenzo[4,5] imidazo[1,2a]pyridine-4-N-(2-fluorophenyl)carboxamide) (RWJ-51204) binds selectively and with high affinity (K(i) = 0.2-2 nM) to the benzodiazepine site on GABA(A) receptors. Considering the GABA shift, the intrinsic modulatory activity of RWJ-51204 is lower than that of full agonist anxiolytics (lorazepam, diazepam, alprazolam, and clonazepam) but similar to partial agonists (bretazenil, abecarnil, panadiplon, and imidazenil). RWJ-51204 was orally active in anxiolytic efficacy tests; pentylenetetrazole induced seizure inhibition in mice (ED(50) = 0.04 mg/kg), Vogel conflict in rats (ED(50) = 0.36 mg/kg), elevated plus-maze in rats (minimal effective dose = 0.1 mg/kg), and conflict in squirrel monkeys (ED(50) = 0.49 mg/kg). RWJ-51204 attenuated chlordiazepoxide-induced motor impairment in mice. Usually, RWJ-51204 was more potent than reference anxiolytics in rodent efficacy tests but less potent in monkey conflict. Usually, the slope of the dose-response lines for RWJ-51204 was more shallow than the full agonist anxiolytics but steeper than partial agonists in efficacy tests but typically shallow in tests for central nervous system side effects. In monkeys only mild or moderate sedation was observed at doses equivalent to 20 or 40 times the anxiolytic ED(50). RWJ-51204 fits into the partial agonist class of GABA(A) receptor modulators. In conclusion, RWJ-51204 exhibits a profile in in vitro experiments and in animal models, in mice and monkeys (but not in rats), suggesting that it has a profile of anxiolytic activity associated with less sedation, motor impairment, or muscle relaxation than currently available GABA(A) receptor modulators, i.e., the benzodiazepines.
Assuntos
Ansiolíticos/farmacologia , Imidazóis/farmacologia , Piridonas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Clordiazepóxido/farmacologia , Conflito Psicológico , Sedação Consciente , Convulsivantes , Interações Medicamentosas , Etanol/farmacologia , Flumazenil/farmacologia , Moduladores GABAérgicos/farmacologia , Lorazepam/farmacologia , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Pentilenotetrazol , Equilíbrio Postural/efeitos dos fármacos , Ratos , Ratos Long-Evans , Receptores de GABA-A/efeitos dos fármacos , Saimiri , Convulsões/induzido quimicamente , Convulsões/prevenção & controleRESUMO
A series of pyrido[1,2-a]benzimidazoles (PBIs) with substitution on the N(5)-nitrogen has been synthesized and found to possess high affinity for the benzodiazepine (BZD) site on the GABA-A receptor. The compounds evaluated include those bearing a heteroalkyl group and heterocyclic rings. The most promising of these compounds is ethoxymethyl analogue 24, which has an IC(50) of 0.1 nM for the BZD site on the GABA-A receptor and has been advanced to human clinical trials.