Description
B-Raf is a MAP kinase kinase kinase, which functions downstream of Ras family GTPases to activate MEK1/2 and ERK1/2 signaling.
1 Mutations of B-Raf, particularly at Val
600, are common in melanomas and melanocytic nevi.
1 CEP-32496 is a potent inhibitor of B-Raf
V600E (K
d = 14 nM in an
in vitro binding assay).
2 It blocks B-Raf
V600E-dependent phosphorylation of MEK in human melanoma A375 and colorectal cancer COLO 205 cells (IC
50s = 78 and 60 nM, respectively).
2 CEP-32496 binds kinases other than B-Raf but displays selective cytotoxicity for cells expressing B-Raf
V600E.
2 It displays good oral bioavailability in rats, dogs, and monkeys and has single oral dose pharmacodynamics inhibition of both pMEK and pERK in B-Raf
V600E colon carcinoma xenografts in nude mice.
2
Synthesis
A 10L Chemglass jacketed reactor, equipped with an N2 inlet/outlet, was charged with 3-[(6,7-dimethoxy-4-quinazolinyl)oxy]aniline (Compound 2, 200.0 g, 637 mmol) and phenyl (5-(1,1,1-trifluoro-2-methylpropan-2-yl)isoxazol-3-yl)carbamate (Compound 3, 177.0 g, 596 mmol). equipped with N2 inlet/outlet, 4-dimethylaminopyridine (DMAP, 2.88 g) and 4.0 L of isopropylacetic acid were added. The internal temperature of the reaction mixture was raised to 70 °C and maintained at this temperature for 9 hours. The slurry was maintained during the reaction and HPLC monitoring showed that compound 2 was completely consumed after a period of heating. Subsequently, 2.0 L of heptane was added at 70 °C and the reaction mixture was cooled to 20 °C. Stirring was continued for 1 h to precipitate the solid, filtered, and the filter cake was washed with 2.0 L of a 1:1 (v/v) isopropyl acetate/heptane solvent mixture. The resulting white solid was dried under vacuum at 55 °C and 75 mbar by N2 exhaust to give 295 g (96% yield) of form A0 product with 99.3% HPLC purity.
References
[1] rowbottom mw1, faraoni r, chao q, campbell bt, lai ag, setti e, ezawa m, sprankle kg, abraham s, tran l, struss b, gibney m, armstrong rc,gunawardane rn, nepomuceno rr, valenta i, hua h, gardner mf, cramer md, gitnick d, insko de, apuy jl, jones-bolin s, ghose ak, herbertz t, ator ma,dorsey bd, ruggeri b, williams m, bhagwat s, james j, holladay mw. identification of 1-(3-(6,7-dimethoxyquinazolin-4-yloxy)phenyl)-3-(5-(1,1,1-trifluoro-2 -methylpropan- 2-yl) isoxazol-3-yl) urea hydrochloride (cep-32496), a highly potent and orally efficacious inhibitor of v-raf murine sarcoma viral oncogene homologue b1 (braf) v600e. j med chem. 2012 feb 9;55(3):1082-105. doi: 10.1021/jm2009925. epub 2012 jan 23.