701945-42-8Relevant articles and documents
Identification of a novel family of BRAFV600E inhibitors
Qin, Jie,Xie, Peng,Ventocilla, Christian,Zhou, Guoqiang,Vultur, Adina,Chen, Quan,Liu, Qin,Herlyn, Meenhard,Winkler, Jeffrey,Marmorstein, Ronen
, p. 5220 - 5230 (2012/08/28)
The BRAF oncoprotein is mutated in about half of malignant melanomas and other cancers, and a kinase activating single valine to glutamate substitution at residue 600 (BRAFV600E) accounts for over 90% of BRAF-mediated cancers. Several BRAFV600E inhibitors have been developed, although they harbor some liabilities, thus motivating the development of other BRAF V600E inhibitor options. We report here the use of an ELISA based high-throughput screen to identify a family of related quinolol/naphthol compounds that preferentially inhibit BRAFV600E over BRAF WT and other kinases. We also report the X-ray crystal structure of a BRAF/quinolol complex revealing the mode of inhibition, employ structure-based medicinal chemistry efforts to prepare naphthol analogues that inhibit BRAF V600E in vitro with IC50 values in the 80-200 nM range under saturating ATP concentrations, and demonstrate that these compounds inhibit MAPK signaling in melanoma cells. Prospects for improving the potency and selectivity of these inhibitors are discussed.
Discovery and synthesis of hydronaphthoquinones as novel proteasome inhibitors
Ge, Yiyu,Kazi, Aslamuzzaman,Marsilio, Frank,Luo, Yunting,Jain, Sanjula,Brooks, Wesley,Daniel, Kenyon G.,Guida, Wayne C.,Sebti, Sa?d M.,Lawrence, Harshani R.
, p. 1978 - 1998 (2012/05/04)
Screening efforts led to the identification of PI-8182 (1), an inhibitor of the chymotrypsin-like (CT-L) activity of the proteasome. Compound 1 contains a hydronaphthoquinone pharmacophore with a thioglycolic acid side chain at position 2 and thiophene sulfonamide at position 4. An efficient synthetic route to the hydronaphthoquinone sulfonamide scaffold was developed, and compound 1 was synthesized in-house to confirm the structure and activity (IC50 = 3.0 ± 1.6 μM [n = 25]). Novel hydronaphthoquinone derivatives of 1 were designed, synthesized, and evaluated as proteasome inhibitors. The structure-activity relationship (SAR) guided synthesis of more than 170 derivatives revealed that the thioglycolic acid side chain is required and the carboxylic acid group of this side chain is critical to the CT-L inhibitory activity of compound 1. Furthermore, replacement of the carboxylic acid with carboxylic acid isosteres such as tetrazole or triazole greatly improves potency. Compounds with a thio-tetrazole or thio-triazole side chain in position 2, where the thiophene was replaced by hydrophobic aryl moieties, were the most active compounds with up to 20-fold greater CT-L inhibition than compound 1 (compounds 15e, 15f, 15h, 15j, IC50 values around 200 nM, and compound 29, IC50 = 150 nM). The synthetic iterations described here not only led to improving potency in vitro but also resulted in the identification of compounds that are more active such as 39 (IC50 = 0.44 to 1.01 μM) than 1 (IC50 = 3.54 to 7.22 μM) at inhibiting the proteasome CT-L activity in intact breast cancer cells. Treatment with 39 also resulted in the accumulation of ubiquitinated cellular proteins and inhibition of tumor cell proliferation of breast cancer cells. The hit 1 and its analogue 39 inhibited proteasome CT-L activity irreversibly.
