RESUMEN
Establishing target engagement is fundamental to effective target-based drug development. It paves the way for efficient medicinal chemistry design and definitive answers about target validation in the clinic. For irreversible targeted covalent inhibitor (TCI) drugs, there is a unique opportunity to establish and quantify the target engagement or occupancy. This is typically accomplished by using a covalent molecular probe, often a TCI analogue, derivatized to allow unoccupied target sites to be tracked; the difference of total sites minus unoccupied sites yields the occupied sites. When such probes are not available or the target is not readily accessible to covalent probes, another approach is needed. Receptor tyrosine-protein kinase erbB-2 (HER2) occupancy by afatinib presents such a case. Available HER2 covalent probes were unable to consistently modify HER2 after sample preparation, resulting in inadequate data. We demonstrate an alternative quantitative probe-free occupancy (PFO) method. It employs the immunoprecipitation of HER2 and direct mass spectrometer analysis of the cysteine-containing peptide that is targeted and covalently occupied by afatinib. Nontarget HER2 peptides provide normalization to the total protein. We show that HER2 occupancy by afatinib correlates directly to the inhibition of the receptor tyrosine kinase activity in NCI-N87 cells in culture and in vivo using those cells in a mouse tumor xenograft mode.
RESUMEN
A lead optimization campaign in our previously reported sulfamoyl benzamide class of CB(2) agonists was conducted to improve the in vitro metabolic stability profile in this series while retaining high potency and selectivity for the CB(2) receptor. From this study, compound 14, N-(3,4-dimethyl-5-(morpholinosulfonyl)phenyl)-2,2-dimethylbutanamide, was identified as a potent and selective CB(2) agonist exhibiting moderate in vitro metabolic stability and oral bioavailability. Compound 14 demonstrated in vivo efficacy in a rat model of post-surgical pain.
Asunto(s)
Compuestos de Anilina/química , Benzamidas/química , Receptor Cannabinoide CB2/agonistas , Sulfonamidas/química , Compuestos de Anilina/síntesis química , Compuestos de Anilina/farmacocinética , Animales , Benzamidas/síntesis química , Benzamidas/farmacocinética , Humanos , Microsomas Hepáticos/metabolismo , Dolor/tratamiento farmacológico , Ratas , Ratas Sprague-Dawley , Receptor Cannabinoide CB2/metabolismo , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/farmacocinéticaRESUMEN
Non-selective cannabinoid ligands display a wide range of physiological effects including analgesic, anti-inflammatory, anti-convulsive and immuno-suppressive activities. A separation between therapeutic effects and undesirable CNS side effects may be accomplished by increasing the selectivity for the CB(2) receptor over the CB(1) receptor. There is considerable interest in developing new cannabimimetic compounds possessing preferentially high affinity for the CB(2) receptor as potential novel therapeutics for the treatment of inflammation and chronic pain. This review will summarize the literature on selective cannabinoid CB(2) receptor agonists from 2007 to the present, with special emphasis on SAR and medicinal chemistry strategies to improve physicochemical properties, metabolic stability and oral bioavailabilty of these inherently lipophilic ligands. Incorporating physicochemical property filters early in hit identification, concurrent screening of liver microsomal stability and addressing metabolic hot-spots through structural modifications or bio-isosteric replacements during lead optimization led to a number of structurally diverse CB(2) agonists with good oral bioavailability and in vivo efficacy in rodent models of pain.
Asunto(s)
Cannabinoides/farmacología , Receptor Cannabinoide CB2/química , Receptor Cannabinoide CB2/efectos de los fármacos , Animales , Cannabinoides/química , Cannabinoides/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Isomerismo , Ligandos , Relación Estructura-Actividad Cuantitativa , Receptor Cannabinoide CB2/agonistas , Receptor Cannabinoide CB2/antagonistas & inhibidoresRESUMEN
Chiral recognition and resolution of methanobenzazocines was investigated by HPLC using polysaccharide, Pirkle-type, native and derivatized beta-cyclodextrin chiral stationary phases. Enantioseparation of phenyl substituted 2,6-methanobenzazocines was achieved with multiple chiral stationary phases throughout the classes described. Chiral resolution of the enantiomers of 1,5-methano-3-methyl-6-oxo-1,2,3,4,5,6-hexahydro-3-benzazocine was produced on both polysaccharide and Pirkle-type phases. In the case of 1,5-methano-3-methyl-6-phenyl-1,2,3,4,5,6-hexahydro-3-benzazocine only a dinitrophenyl substituted beta-cyclodextrin produced a separation of enantiomers.
Asunto(s)
Benzomorfanos/química , Cromatografía Líquida de Alta Presión/métodos , EstereoisomerismoRESUMEN
Replacement of the phenyl ring in our previous (morpholinomethyl)aniline carboxamide cannabinoid receptor ligands with a pyridine ring led to the discovery of a novel chemical series of CB2 ligands. Compound 3, that is, 2,2-dimethyl-N-(5-methyl-4-(morpholinomethyl)pyridin-2-yl)butanamide was identified as a potent and selective CB2 agonist exhibiting in vivo efficacy after oral administration in a rat model of neuropathic pain.
Asunto(s)
Aminopiridinas/química , Morfolinas/química , Piridinas/química , Receptor Cannabinoide CB2/agonistas , Administración Oral , Aminopiridinas/síntesis química , Aminopiridinas/farmacología , Animales , Perros , Humanos , Masculino , Microsomas Hepáticos , Morfolinas/síntesis química , Morfolinas/farmacología , Dolor/tratamiento farmacológico , Unión Proteica , Piridinas/síntesis química , Piridinas/farmacocinética , Ratas , Ratas Sprague-Dawley , Receptor Cannabinoide CB1/agonistas , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/metabolismo , Relación Estructura-ActividadRESUMEN
Recently sulfamoyl benzamides were identified as a novel series of cannabinoid receptor ligands. Replacing the sulfonamide functionality and reversing the original carboxamide bond led to the discovery of N-(3-(morpholinomethyl)-phenyl)-amides as potent and selective CB(2) agonists. Selective CB(2) agonist 31 (K(i)=2.7; CB(1)/CB(2)=190) displayed robust activity in a rodent model of postoperative pain.
Asunto(s)
Antiinflamatorios/química , Benzamidas/química , Receptor Cannabinoide CB2/agonistas , Animales , Antiinflamatorios/síntesis química , Antiinflamatorios/farmacología , Benzamidas/síntesis química , Benzamidas/farmacología , Células CHO , Línea Celular , Cricetinae , Cricetulus , Descubrimiento de Drogas , Humanos , Dolor Postoperatorio/tratamiento farmacológico , Ratas , Receptor Cannabinoide CB2/metabolismo , Estereoisomerismo , Relación Estructura-Actividad , TransfecciónRESUMEN
Previous research within our laboratories identified sulfamoyl benzamides as novel cannabinoid receptor ligands. Optimization of the amide linkage led to the reverse amide 40. The compound exhibited robust antiallodynic activity in a rodent pain model when administered intraperitoneally. Efficacy after oral administration was observed only when ABT, a cytochrome P450 suicide inhibitor, was coadministered.
Asunto(s)
Benzamidas/farmacología , Receptor Cannabinoide CB2/efectos de los fármacos , Animales , Benzamidas/administración & dosificación , Benzamidas/química , Benzamidas/uso terapéutico , Dolor/tratamiento farmacológico , RoedoresRESUMEN
Sulfamoyl benzamides were identified as a novel series of cannabinoid receptor ligands. Starting from a screening hit 8 that had modest affinity for the cannabinoid CB(2) receptor, a parallel synthesis approach and initial SAR are described, leading to compound 27 with 120-fold functional selectivity for the CB(2) receptor. This compound produced robust antiallodynic activity in rodent models of postoperative pain and neuropathic pain without traditional cannabinergic side effects.
Asunto(s)
Benzamidas/uso terapéutico , Neuralgia/tratamiento farmacológico , Receptor Cannabinoide CB2/metabolismo , Sulfonamidas/uso terapéutico , Animales , Benzamidas/síntesis química , Benzamidas/farmacología , Sitios de Unión , Relación Dosis-Respuesta a Droga , Ligandos , Ratones , Modelos Animales , Modelos Químicos , Dimensión del Dolor/efectos de los fármacos , Ratas , Receptor Cannabinoide CB2/química , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/farmacologíaRESUMEN
Synthesis, in vitro biological evaluation, and structure-activity relationships of a biaryl cannabinoid mimetic 2 are reported. Variations in the substitution pattern yielded a number of agonists with low nanomolar affinity. Replacing the phenol group by a methyl morpholino acetate group led to compound 28, a 500-fold selective CB(2) receptor agonist.
Asunto(s)
Cannabinoides/química , Cannabinoides/síntesis química , Química Farmacéutica/métodos , Ácidos Carboxílicos/química , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Humanos , Hidrógeno/química , Enlace de Hidrógeno , Inmunosupresores/química , Concentración 50 Inhibidora , Cinética , Modelos Químicos , Parasimpatolíticos , Fenol/química , Unión ProteicaRESUMEN
10-Hydroxy-10,9-boroxarophenanthrenes were obtained as unexpected major products upon BBr(3)-mediated O-demethylation of 2-methoxybiaryls. The formation likely proceeds via intramolecular electrophilic aromatic cyclization of a reactive dibromoaryloxyborane intermediate. Essentially quantitative yields of 10-hydroxy-10,9-boroxarophenanthrenes were also obtained from 2-hydroxybiaryl and BCl(3)/AlCl(3) with use of a modified literature procedure. As synthetic intermediates, 10-hydroxy-10,9-boroxarophenanthrenes were efficiently converted to 3,4-benzocoumarins and triaryls through Pd-catalyzed CO insertion and Suzuki reaction.
RESUMEN
Cationic phosphine ligands containing m-guanidinium phenyl substituents {Ph(3-n)P[C(6)H(4)-m-NHC(NH(2))(NMe(2))](n)}(n+) nCl(-) (n = 1-3) (17a-c) have been obtained by addition of dimethylcyanamide to the amino groups of tertiary (m-aminophenyl)phosphines in acidic medium. The tertiary (m-aminophenyl)phosphines Ph(3-n)P(C(6)H(4)-m-NH(2))(n) (4a-c) were prepared by reaction of (3-[N,N-bis(trimethylsilyl)amino]phenyl)magnesium chloride (1) with chlorophosphines Ph(3-n)PCl(n) followed by deprotection of the bis(trimethylsilyl)amino groups with methanol. Using a similar protected group synthesis as above, the secondary (m-aminophenyl)phosphine Ph(H)PC(6)H(4)-m-NH(2) (7) could be prepared as well. It may be employed as a building block for the syntheses of chiral bidentate phosphine ligands (11, 14, and 15) bearing m-aminophenyl substituents. The guanidinium phosphines 17b and 17c are readily soluble in water. A comparative study of 17b and 17c, the aryl alkyl guanidinium phosphines 18 and 19, and TPPTS (P(C(6)H(4)-m-SO(3)Na)(3)) in the aqueous phase palladium-catalyzed C-C coupling reaction between p-iodobenzoate and (trifluoroacetyl)propargylamine shows 17b to be of surmounting activity.