2767-70-6Relevant articles and documents
Oxalylmethylenephosphoranes. 2. Synthesis and biological activity of some methylenetriphenylphosphoranes and phosphonium salts containing an acyl moiety
Koz'minykh, V. O.,Shavkunova, G. A.,Berezina, E. S.,Igidov, N. M.,Koz'minykh, E. N.,et al.
, p. 906 - 911 (1994)
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Femtosecond Transient Grating Studies of Chlorophylls and Chlorophyll-Based Electon Donor-Acceptor Molecule
Wiederrecht, Gary P.,Svec, Walter A.,Niemczyk, Mark P.,Wasielewski, Michael R.
, p. 8918 - 8926 (1995)
Ultrafast, polarization selective, transient grating studies are performed on several chlorophylls and an electron donor-acceptor molecule, Zn DMPPH-PI, that consists of a zinc methyl 131-desoxopyropheophorbide a donor covalently linked to a pyromellitimide acceptor.The covalent linkage between the donor and acceptor constrains the distance and geometric relationship between them.The ability of the experiment to determine the nature of a particular physical phenomenon through separable polarization characteristics of the diffracted signal is used to analyze photophysical and photochemical processes in these molecules.This is achieved for cases in which the observed physical processes have overlapping spectral contributions, a situation where linear dichroism experiments are very difficult to interpret.Careful analysis of the absorption grating data allows us to determine rotational anisotropy values for the molecules in solution, two-photon absorption-state symmetries, and the relative orientation of the donor and acceptor in the Zn DMPPH-PI molecule.These results demonstrate complete separation of the contributions to the time dependent diffracted signal from the two radical ion pair products formed in the electron transfer reaction.
Substituted dienes prepared from betulinic acid – Synthesis, cytotoxicity, mechanism of action, and pharmacological parameters
Frydrych, Ivo,Urban, Milan,?arek, Jan,Benická, Sandra,D?ubák, Petr,Gurská, Soňa,Hajdúch, Marián,Kotulová, Jana,Li?ková, Barbora,Olejníková, Denisa,Pokorny, Jan
, (2021/07/28)
A set of new substituted dienes were synthesized from betulinic acid by its oxidation to 30-oxobetulinic acid followed by the Wittig reaction. Cytotoxicity of all compounds was tested in vitro in eight cancer cell lines and two noncancer fibroblasts. Almost all dienes were more cytotoxic than betulinic acid. Compounds 4.22, 4.30, 4.33, 4.39 had IC50 below 5 μmol/L; 4.22 and 4.39 were selected for studies of the mechanism of action. Cell cycle analysis revealed an increase in the number of apoptotic cells at 5 × IC50 concentration, where activation of irreversible changes leading to cell death can be expected. Both 4.22 and 4.39 led to the accumulation of cells in the G0/G1 phase with partial inhibition of DNA/RNA synthesis at 1 × IC50 and almost complete inhibition at 5 × IC50. Interestingly, compound 4.39 at 5 × IC50 caused the accumulation of cells in the S phase. Higher concentrations of tested drugs probably inhibit more off-targets than lower concentrations. Mechanisms disrupting cellular metabolism can induce the accumulation of cells in the S phase. Both compounds 4.22 and 4.39 trigger selective apoptosis in cancer cells via intrinsic pathway, which we have demonstrated by changes in the expression of the crucial apoptosis-related protein. Pharmacological parameters of derivative 4.22 were superior to 4.39, therefore 4.22 was the finally selected candidate for the development of anticancer drug.
Cis alkenes stabilized by intramolecular sulphur?π interactions
Zhao, Xiaolei,Zheng, Wei,Zhang, Yi,Huang, Wei
supporting information, p. 814 - 817 (2020/01/29)
A series of alkenes with bistable isomers were obtained containing a thiophene/azoheteroaryl backbone. Visible light and heat-induced reversible cis ? trans isomerizations were evidenced by UV-Vis and 1H NMR spectra. The stabilization of cis alkenes was attributed to intramolecular sulphur?π (S?π) interactions, which were further supported by theoretical calculations.
