2971-17-7Relevant academic research and scientific papers
Characterization of 2-Oxindole Forming Heme Enzyme MarE, Expanding the Functional Diversity of the Tryptophan Dioxygenase Superfamily
Zhang, Yuyang,Zou, Yi,Brock, Nelson L.,Huang, Tingting,Lan, Yingxia,Wang, Xiaozheng,Deng, Zixin,Tang, Yi,Lin, Shuangjun
, p. 11887 - 11894 (2017/09/07)
3-Substituted 2-oxindoles are important structural motifs found in many biologically active natural products and pharmaceutical lead compounds. Here, we report an enzymatic formation of the 3-substituted 2-oxindoles catalyzed by MarE in the maremycin biosynthetic pathway in Streptomyces sp. B9173. MarE is a homologue of FeII/heme-dependent tryptophan 2,3-dioxygenases (TDOs). Typical TDOs usually catalyze the insertion of two oxygen atoms from O2 into an indole ring to generate N-formylkynurenine (NFK)-like products. In contrast, MarE catalyzes the insertion of a single oxygen atom from O2 into an indole ring, to probably generate an epoxyindole intermediate that undergoes an unprecedented 2,3-hydride migration to form 2-oxindole structure. MarE shows substrate robustness to catalyze the conversion of a series of 3-substituted indoles into their corresponding 3-substituted 2-oxindoles. Although containing most key amino acid residues conserved in well-known TDO homologues, MarE falls into a separate new subgroup in the phylogenetic tree. The characterization of MarE and its homologue enriches the functional diversities of TDO superfamily and provides a new strategy for discovering novel natural products containing 3-substituted 2-oxindole pharmacophores by genome mining.
Tyrosine kinase inhibitors. 1. Structure-activity relationships for inhibition of epidermal growth factor receptor tyrosine kinase activity by 2,3-dihydro-2-thioxo-1H-indole-3-alkanoic acids and 2,2'-dithiobis(1H- indole-3-alkanoic acids)
Thompson,Rewcastle,Tercel,Dobrusin,Fry,Kraker,Denny
, p. 2459 - 2469 (2007/10/02)
A series of 2,3-dihydro-2-thioxo-1H-indole-3-alkanoic acids, and their methyl esters were prepared, the majority by oxidation of 1H-indole-3- alkanoic acids (DMSO/HCl), followed by thiation of the corresponding 2,3- dihydro-2-oxo-1H-indole-3-alkanoic acid esters. The monomeric thiones undergo facile and reversible oxidation to the corresponding 2,2'-dithiobis(1H- indole-3-alkanoic acids). The compounds were evaluated for their abilities to inhibit the tyrosine kinase activity of the epidermal growth factor receptor using a native complex contained in plasma membrane vesicles shed from cultured A431 cells, and to inhibit the growth of Swiss 3T3 mouse fibroblast in culture. Enzyme inhibitory activity is dependent on the length of the side chain, with propanoic acid derivatives showing the highest activity. The acids are generally significantly more potent than the corresponding esters, and the disulfides more active than the corresponding monomers. An ability to undergo the thione-thiol tautomerism necessary for dimerization is essential, with 3,3-disubstituted compounds being inactive. Overall, the data suggest that the disulfide is the more active form, with much of the activity of the monomeric thiones being due to varying degrees of conversion to the disulfide during the assay. In the growth inhibition assay, the methyl esters are more potent than their corresponding carboxylic acids, and the dimers are generally more potent than the monomers. The data show these compounds to be a novel and potent class of inhibitors of epidermal growth factor receptor tyrosine kinase activity.
