77-95-2Relevant articles and documents
Eucommicin A, a β-truxinate lignan from Eucommia ulmoides, is a selective inhibitor of cancer stem cells
Fujiwara, Ayaka,Nishi, Mayuko,Yoshida, Shigeo,Hasegawa, Morifumi,Yasuma, Chieko,Ryo, Akihide,Suzuki, Yoshihito
, p. 139 - 145 (2016)
Cancer stem cells (CSCs) constitute a small population of undifferentiated cells within a tumor that have the ability to self-renew and drive tumor formation, thus behaving as cancer-initiating cancer cells. Therapeutic interventions that eliminate CSCs are necessary to completely cure patients, since CSCs are a crucial source of tumor recurrence and metastasis. An induced CSC-like (iCSCL) model was recently established using induced pluripotent stem cells (iPSCs). In this study, a natural product - eucommicin A - was identified from Eucommia ulmoides leaves by screening for anti-CSC activity using the iCSCL model. Its structure was elucidated by spectroscopic methods as a quinic acid diester of 3,4,3′,4′-tetrahydroxy-β-truxinic acid. Eucommicin A exhibited selective anti-CSC activity and inhibited tumor sphere formation by iCSCL cells. The results of this study suggest that eucommicin A could serve as a lead compound in the development of drugs to abrogate the stemness and self-renewal ability of CSCs.
SEVEN QUINIC ACID GALLATES FROM QUERCUS STENOPHYLLA
Nishimura, Hiroaki,Nonaka, Gen-Ichiro,Nishioka, Itsuo
, p. 2621 - 2624 (1984)
A chemical investigation of the bark of Quercus stenophylla has led to the isolation and characterization of all of the possible structural isomers of quinic acid gallates; 3-O-, 4-O-, 5-O-, 3,4-di-O-, 3,5-di-O-, 4,5-di-O- and 3,4,5-tri-O-galloylquinic acids.Evidence for the structures of these compounds was obtained from analysis of the 1H and 13C NMR spectra, and hydrolytic studies.Key Word Index - Quercus stenophylla; Fagaceae; quinic acid gallates; gallotannins; tannase.
Analysis of protein-phenolic compound modifications using electrochemistry coupled to mass spectrometry
Kallinich, Constanze,Schefer, Simone,Rohn, Sascha
, (2018/02/07)
In the last decade, electrochemical oxidation coupled with mass spectrometry has been successfully used for the analysis of metabolic studies. The application focused in this study was to investigate the redox potential of different phenolic compounds such as the very prominent chlorogenic acid. Further, EC/ESI-MS was used as preparation technique for analyzing adduct formation between electrochemically oxidized phenolic compounds and food proteins, e.g., alpha-lactalbumin or peptides derived from a tryptic digestion. In the first step of this approach, two reactant solutions are combined and mixed: one contains the solution of the digested protein, and the other contains the phenolic compound of interest, which was, prior to the mixing process, electrochemically transformed to several oxidation products using a boron-doped diamond working electrode. As a result, a Michael-type addition led to covalent binding of the activated phenolic compounds to reactive protein/peptide side chains. In a follow-up approach, the reaction mix was further separated chromatographically and finally detected using ESI-HRMS. Compound-specific, electrochemical oxidation of phenolic acids was performed successfully, and various oxidation and reaction products with proteins/peptides were observed. Further optimization of the reaction (conditions) is required, as well as structural elucidation concerning the final adducts, which can be phenolic compound oligomers, but even more interestingly, quite complex mixtures of proteins and oxidation products.
An easy 'Filter-and-Separate' method for enantioselective separation and chiral sensing of substrates using a biomimetic homochiral polymer
Senthilkumar,Asha
supporting information, p. 8931 - 8934 (2015/05/27)
We present a polyfluorene appended with protected l-glutamic acid that exhibited a reversible α-helix/β-sheet-like conformation and helical porous fibrous morphology mimicking the super-structure of proteins. The new homochiral polymer probe enabled efficient heterogeneous enantioselective separation and chiral sensing of a wide variety of substrates from their aqueous racemic mixture using an easy 'Filter-and-Separate' method.