73094-37-8Relevant articles and documents
Stereospecific modulation of dimeric rhodopsin
Chen, Yuanyuan,Getter, Tamar,Gulati, Sahil,Palczewski, Krzysztof,Vinberg, Frans,Zimmerman, Remy
, p. 9526 - 9539 (2020/02/27)
The classic concept that GPCRs function as monomers has been challenged by the emerging evidence of GPCR dimerization and oligomerization. Rhodopsin (Rh) is the only GPCR whose native oligomeric arrangement was revealed by atomic force microscopy demonstrating that Rh exists as a dimer. However, the role of Rh dimerization in retinal physiology is currently unknown. In this study, we identified econazole and sulconazole, two small molecules that disrupt Rh dimer contacts, by implementing a cell-based high-throughput screening assay. Racemic mixtures of identified lead compounds were separated and tested for their stereospecific binding to Rh using UV-visible spectroscopy and intrinsic fluorescence of tryptophan (Trp) 265 after illumination. By following the changes in UV-visible spectra and Trp265 fluorescence in vitro, we found that binding of R-econazole modulates the formation of Meta III and quenches the intrinsic fluorescence of Trp265. In addition, electrophysiological ex vivo recording revealed that R-econazole slows photoresponse kinetics, whereas S-econazole decreased the sensitivity of rods without effecting the kinetics. Thus, this study contributes new methodology to identify compounds that disrupt the dimerization of GPCRs in general and validates the first active compounds that disrupt the Rh dimer specifically.—Getter, T., Gulati, S., Zimmerman, R., Chen, Y., Vinberg, F., Palczewski, K. Stereospecific modulation of dimeric rhodopsin. FASEB J. 33, 9526–9539 (2019). www.fasebj.org.
Diamine-Tethered Bis(thiourea) Organocatalyst for Asymmetric Henry Reaction
Otevrel, Jan,Bobal, Pavel
, p. 8342 - 8358 (2017/08/23)
We have developed a novel multifunctional C2-symmetric biphenyl-based diamine-tethered bis(thiourea) organocatalyst, which was tested in the asymmetric Henry reaction. Under thoroughly optimized conditions, the catalyst provided exceptionally high yields and excellent enantioselectivities especially for electron-deficient aromatic and heterocyclic substrates. Due to a high affinity of the catalyst to silica gel, a simple chromatography-free nitroaldol isolation procedure was feasible. Preliminary kinetic and spectroscopic experiments were performed in order to complete the mechanistic picture of the organocatalyzed nitroaldolization process. Finally, the developed synthetic strategy was successfully applied to the catalytic enantioselective syntheses of enantiopure (S)-econazole and (R)-mirabegron a late-stage intermediate.
Discovery of a small molecule targeting ULK1-modulated cell death of triple negative breast cancer in vitro and in vivo
Zhang, Lan,Fu, Leilei,Zhang, Shouyue,Zhang, Jin,Zhao, Yuqian,Zheng, Yaxin,He, Gu,Yang, Shengyong,Ouyang, Liang,Liu, Bo
, p. 2687 - 2701 (2017/04/06)
UNC-51-like kinase 1 (ULK1) is well-known to initiate autophagy, and the downregulation of ULK1 has been found in most breast cancer tissues. Thus, the activation of ULK1-modulated autophagy could be a promising strategy for breast cancer therapy. In this study, we found that ULK1 was remarkably downregulated in breast cancer tissue samples by The Cancer Genome Atlas (TCGA) analysis and tissue microarray (TMA) analysis, especially in triple negative breast cancer (TNBC). To design a ULK1 agonist, we integrated in silico screening and chemical synthesis to acquire a series of small molecule candidates. After rounds of kinase and anti-proliferative activity screening, we discovered the small molecule, LYN-1604, to be the best candidate for a ULK1 agonist. Additionally, we identified that three amino acid residues (LYS50, LEU53, and TYR89) were key to the activation site of LYN-1604 and ULK1 by site-directed mutagenesis and biochemical assays. Subsequently, we demonstrated that LYN-1604 could induce cell death, associated with autophagy by the ULK complex (ULK1-mATG13-FIP200-ATG101) in MDA-MB-231 cells. To further explore LYN-1604-induced autophagic mechanisms, we found some potential ULK1 interactors, such as ATF3, RAD21, and caspase3, by performing comparative microarray analysis. Intriguingly, we found that LYN-1604 induced cell death involved in ATF3, RAD21, and caspase3, accompanied by autophagy and apoptosis. Moreover, we demonstrated that LYN-1604 has potential for good therapeutic effects on TNBC by targeting ULK1-modulated cell death in vivo; thus making this ULK1 agonist a novel potential small-molecule drug candidate for future TNBC therapy.
