RESUMO
A series of 6- or 7-methylchroman-2-carboxylic acid N-(substituted) phenylamides (2a-s, 3a-s) were synthesized. Their abilities to inhibit nuclear factor-kappaB (NF-kappaB) activity were evaluated in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. Compounds with substituents such as -H, -CH(3), and -CF(3) on the phenyl ring were poor inhibitors of NF-kappaB. The most active NF-kappaB inhibitors contained 4-Cl (3s) and 4-OMe (3g) in the 7-methylchroman-2-carboxamide derivatives and 2-OH (2b) and 4-Cl (2s) in the 6-methylchroman-2-carboxamide derivatives (IC(50): 20.2-24.0 microM). These were slightly more potent than a reference compound, KL-1156 (1) (IC(50): 43.9 microM).
Assuntos
Cromanos/síntese química , Cromanos/farmacologia , NF-kappa B/antagonistas & inibidores , Animais , Linhagem Celular , Cromanos/química , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Relação Estrutura-AtividadeRESUMO
A series of chroman-2-carboxylic acid N-(substituted)phenylamides (2a-s, 3a-j) were synthesized. Their ability to inhibit nuclear factor-kappaB (NF-kappaB) activity was evaluated in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells and their antioxidant activity was examined. NF-kappaB inhibition by chroman compounds was not related to their antioxidant activity. Compounds with -H, -NO2 monosubstituents and -OCH3, -CF3 disubstituents on the phenyl ring were poor inhibitors of NF-kB activity. Compounds with -CH3, -CF3, -CI monosubstituents or -CI, -CH3 disubstituents exhibited moderate to good NF-kappaB activity inhibition (IC50: 18.2-95.8 microM). The most active NF-kappaB inhibitor, 2s, contained a 4-CI (IC50: 18.2 microM) substituent on the phenyl ring and was slightly more potent than the compound KL-1156 (1) (IC50: 43.9 microM).
Assuntos
Cromanos/síntese química , Cromanos/farmacologia , NF-kappa B/antagonistas & inibidores , Animais , Antioxidantes/farmacologia , Compostos de Bifenilo , Química Encefálica/efeitos dos fármacos , Linhagem Celular , Sequestradores de Radicais Livres/farmacologia , Indicadores e Reagentes , Peroxidação de Lipídeos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Camundongos , NF-kappa B/biossíntese , NF-kappa B/genética , Picratos/farmacologia , Ratos , Relação Estrutura-Atividade , Transcrição GênicaRESUMO
4,4-Dimethyloxazolones derived from N-protected aminoisobutyric acid (AIB) are particularly known as poor electrophiles due to the steric hindrance around the carbonyl and not employed as useful intermediates for amidation whereas numerous examples have been reported to support the utility of other oxazolones in amidation. AIB is an important and strategical synthon in medicinal chemistry but the peptide bond formation of the N-protected urethane derivatives of AIB is known to be often unproductive due to the rapid formation of the stable 4,4-dimethyloxazolone via an intramolecular cyclization. We discovered that the 4,4-dimethyloxazolone of an AIB urethane is in fact an excellent electrophile that enables efficient amidation even with weakly reactive nucleophiles. The 4,4-dimethyloxazolone can be stored in a pure form and used as a reagent offering an efficient and convenient synthetic tool for generating AIB-peptide analogs.
Assuntos
Amidas/química , Ácidos Aminoisobutíricos/síntese química , Oxazolona/química , Ácidos Aminoisobutíricos/química , Estrutura MolecularRESUMO
Aminoisobutyric acid (AIB) is an important building block widely incorporated by medicinal chemists in molecular design. Owing to the steric challenge, elaborating AIB's carboxylic acid using conventional amidation protocols is often problematic. We discovered that an amidation protocol utilizing methyl Boc-aminoisobutyrate and magnesium amidates of various reactivities produces the corresponding amide derivatives in good to excellent yields.