105016-76-0Relevant academic research and scientific papers
The Halicylindramides, Farnesoid X Receptor Antagonizing Depsipeptides from a Petrosia sp. Marine Sponge Collected in Korea
Hahn, Dongyup,Kim, Hiyoung,Yang, Inho,Chin, Jungwook,Hwang, Hoosang,Won, Dong Hwan,Lee, Byoungchan,Nam, Sang-Jip,Ekins, Merrick,Choi, Hyukjae,Kang, Heonjoong
, p. 499 - 506 (2016)
Three new structurally related depsipeptides, halicylindramides F-H (1-3), and two known halicylindramides were isolated from a Petrosia sp. marine sponge collected off the shore of Youngdeok-Gun, East Sea, Republic of Korea. Their planar structures were elucidated by extensive spectroscopic data analyses including 1D and 2D NMR data as well as MS data. The absolute configurations of halicylindramides F-H (1-3) were determined by Marfey's method in combination with Edman degradation. The absolute configurations at C-4 of the dioxyindolyl alanine (Dioia) residues of halicylindramides G (2) and H (3) were determined as 4S and 4R, respectively, based on ECD spectroscopy. The C-2 configurations of Dioia in 2 and 3 were speculated to both be 2R based on the shared biogenesis of the halicylindramides. Halicylindramides F (1), A (4), and C (5) showed human farnesoid X receptor (hFXR) antagonistic activities, but did not bind directly to hFXR.
Synthesis of 2-bromo-L-tryptophan and 2-chloro-L-tryptophan
Phillips,Cohen
, p. 5555 - 5558 (1983)
Free-radical halogenation of protected L-tryptophan with N-bromosuccinimide or N-chlorosuccinimide leads to the corresponding 2-halo derivative in high yield; enzymatic removal of the blocking groups provides the new amino acid analogues.
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.
