RESUMEN
The same two major CYP mediated metabolites of DG-051 were produced in the presence of rat, dog, monkey and human liver microsomes. Their respective structures were hypothesized based on mass spectrometry data correlated with the parent structure and confirmed by comparison with authentic synthetic samples. The number of regioisomers synthesized as candidates for metabolite M1 was narrowed down using a metabolic study of a selectively deuterated DG-051 analogue.
Asunto(s)
Inhibidores Enzimáticos/química , Epóxido Hidrolasas/antagonistas & inhibidores , Microsomas Hepáticos/metabolismo , Espectrofotometría Ultravioleta/métodos , Anestésicos Disociativos , Animales , Cromatografía Líquida de Alta Presión , Citocromo P-450 CYP3A/metabolismo , Perros , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Humanos , Espectrometría de Masas/métodos , Metabolómica , Estructura Molecular , Ratas , Bibliotecas de Moléculas Pequeñas , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodosRESUMEN
The Mitsunobu reaction was used to attach tetra-O-benzyl-D-glucopyranose to a monoindolylmaleimide, providing a key intermediate in the total synthesis of indolocarbazole topoisomerase I poisons. Using normal-phase silica gel chromatography, purification of the glycosylated product normally required multiple columns, resulting in poor recovered yields. Reversed-phase chromatography was used successfully to purify this highly hydrophobic material, rapidly and in high yield.
Asunto(s)
Inhibidores Enzimáticos/síntesis química , Indoles/química , Inhibidores de Topoisomerasa I , Carbazoles/química , Cromatografía Liquida , Glucosa/análogos & derivados , Glucosa/química , Glicosilación , Espectroscopía de Resonancia MagnéticaRESUMEN
The indolo[2,3-a]carbazole alkaloids constitute an important class of natural products with interesting and diverse biological activities. A series of novel ring-fused indolocarbazoles were synthesized and evaluated for inhibition of topoisomerase I-mediated relaxation of supercoiled DNA and in vitro antitumor activity. The derivatives bearing a methylenedioxy or an ethylenedioxy ring fused onto the nonglycosylated indole (1a, 1b) demonstrated more potent anti-topoisomerase I activity. The isopropylenedioxy analogue 1c was approximately half as active as 1a, while the O-dimethoxy analogue 1d and the regioisomers 2a and 2b were essentially devoid of measurable activity, implying that the stacking with the intact DNA strand has been impeded by these compounds due to steric hindrance. The newly synthesized indolocarbazoles were screened against the NCI's 60 tumor cell lines. The order of activity, based on the mean GI50 values, is as follows: 1a > 2a ~ 1d > 1b > MCR-47 > 2b. Though in general the analogues that showed potent activity against topoisomerase I (1a, 1b) also showed potent in vitro inhibition of tumor cell growth, the antitumor activity of the anti-topoisomerase I inactive 1d and 2a were intriguing. COMPARE analyses confirmed that the topoisomerase I is the primary target for 1a and 1b; however, other target(s) or pathway(s) may also be involved, with PLD1 and MERTK suggested. Further investigation of these molecular targets against these indolocarbazoles is warranted.
Asunto(s)
Antineoplásicos/química , Carbazoles/química , ADN-Topoisomerasas de Tipo I/metabolismo , Indoles/química , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Inhibidores de Topoisomerasa I/química , Antineoplásicos/farmacología , Carbazoles/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Indoles/farmacología , Relación Estructura-Actividad , Inhibidores de Topoisomerasa I/farmacologíaRESUMEN
The EP(3) receptor on the platelet mediates prostaglandin E(2) potentiation of thrombogenic coagonists including collagen and adenosine diphosphate (ADP). A pharmacophore driven approach led to the identification of diverse peri-substituted heterocycles as potent and selective EP(3) receptor antagonists. A simultaneous chemical optimization and druglike assessment of prioritized molecules converged on a lead compound 50 (DG-041) that displayed favorable in vitro and functional activities as an inhibitor of human platelet aggregation. This agent is currently in human clinical trials for the treatment of atherothrombosis.
Asunto(s)
Acrilamidas/farmacología , Hemorragia , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Receptores de Prostaglandina E/antagonistas & inhibidores , Sulfonas/farmacología , Acrilamidas/síntesis química , Acrilamidas/química , Coagulación Sanguínea/efectos de los fármacos , Descubrimiento de Drogas , Humanos , Ligandos , Estructura Molecular , Inhibidores de Agregación Plaquetaria/síntesis química , Inhibidores de Agregación Plaquetaria/química , Subtipo EP3 de Receptores de Prostaglandina E , Estereoisomerismo , Relación Estructura-Actividad , Sulfonas/síntesis química , Sulfonas/químicaRESUMEN
Both in-house human genetic and literature data have converged on the identification of leukotriene 4 hydrolase (LTA(4)H) as a key target for the treatment of cardiovascular disease. We combined fragment-based crystallography screening with an iterative medicinal chemistry effort to optimize inhibitors of LTA(4)H. Ligand efficiency was followed throughout our structure-activity studies. As applied within the context of LTA(4)H inhibitor design, the chemistry team was able to design a potent compound 20 (DG-051) (K(d) = 26 nM) with high aqueous solubility (>30 mg/mL) and high oral bioavailability (>80% across species) that is currently undergoing clinical evaluation for the treatment of myocardial infarction and stroke. The structural biology-chemistry interaction described in this paper provides a sound alternative to conventional screening techniques. This is the first example of a gene-to-clinic paradigm enabled by a fragment-based drug discovery effort.