226879-00-1Relevant articles and documents
Stereoselective photoinduced electron-transfer reaction between zinc myoglobin and new chiral quinolinium ions
Tsukahara, Keiichi,Ueda, Rie
, p. 561 - 566 (2003)
New chiral quinolinium derivatives, 1-[(S)- or (R)-(1-phenylethyl)carbamoylmethyl]-6-methoxyquinolinium hexafluorophosphate ([PMQ]PF6, 2) and 1-[(S)- or (R)-(1-phenylethyl)carbamoylmethyl]quinolinium hexafluorophosphate ([PQ]PF6, 3), were synthesized and characterized. A cyclic voltammetry in MeCN shows an irreversible redox behavior at -0.88 V and -0.85 V vs SCE (saturated calomel electrode) for 2 and 3, respectively. Fluorescence from the quinolinium moiety of 2 and 3 was observed at 455 nm and 440 nm, respectively. The fluorescence lifetime of 2 was longer than that of 3: τf = 30 ns (2) and 20 ns (3) in MeCN and τf = 26 ns (2) and 16 ns (3) in H2O). The excited triplet state of zinc-substituted myoglobin (3(ZnMb)*) was quenched by chiral [PMQ]+ and [PQ]+ ions; thereafter, the back electron-transfer (ET) reaction from a quinoline radical (PMQ. or PQ. to a zinc myoglobin radical cation was detected. The stereoselectivity was observed for both ET quenching and back ET reactions; the (S)-isomers preferentially quench 3(ZnMb)* (kq(S)/kq(R) = 1.3 and 1.4 at 25°C for [PMQ]+ and [PQ]+, respectively); in contrast, the (R)-isomers react faster than the (S)-isomers in the back ET reaction (kb(R)/kb(S) = 1.3 and 1.4 for PMQ. and PQ., respectively). From a comparison of the rate constants with those for the previously reported systems we suggest that both the quenching and back reactions are controlled by ET, but not by conformational gating.
Effect of chirality and redox potentials on the cytotoxicity of new ferrocene functionalized chiral tertiary amines
Roy, Hetal,Savani, Chirag J.,Singh, Vinay K.,Vennapu, Dushyanth R.
, (2021/08/03)
Optically pure enantiomeric pair viz. ferrocene functionalized chiral tertiary amines S,S-(-)-1 and R,R-(+)-2 have been synthesized from ferrocenylmethylamine to probe the influence of chirality and the redox potential on their anti-proliferative activity. Compounds were characterized by microanalysis, HPLC, 1H, 13C NMR, UV-visible, fluorescence, FTIR, thermogravimetric and crystallographic techniques. The single crystal X-ray diffraction (SCXRD) study revealed that the molecules of 1 holding S,S-chirality at benzylic carbons forms a fascinating M-helix while 2 holding R,R-chirality at benzylic carbons forms P-helix by involving intra- and intermolecular H-bonding interactions as verified by Hirshfeld surface analysis. Chirality-related influence was observed on the antiproliferative activity of enantiomeric pair and at the supramolecular level. For instance, enantiomer R,R-(+)-2 is found to be highly active against all the investigated human carcinoma cell lines MCF 7, IMR 32, HepG2, and immortal L132 cell lines. In particular, R,R-(+)-2 exhibited more than 10 folds better antiproliferation (IC 50: 6.35±0.19 μM) than other enantiomer S,S-(-)-1 (IC50: 65.96 ± 0.12 μM) and four folds better activity than highly successful anticancer drug, cisplatin (IC50: 24.3 ± 1.7 μM) against Hep G2 cell line. The electrochemical, DFT calculations and molecular docking study have been performed to justify the experimental outcomes.
Metabotropic glutamate receptor antagonists and their use for treating central nervous system diseases
-
, (2008/06/13)
The present invention provides compounds, and pharmaceutical compositions containing those compounds, that are active at metabotropic glutamate receptors. The compounds are useful for treating neurological diseases and disorders. Methods of preparing the compounds also are disclosed.
