3405-88-7Relevant articles and documents
A highly stereoselective oxidation and an easy one pot elimination methodology for 3-allyl-3-phenylthio-β-lactams
Bari, Shamsher S.,Nagpal, Reshma,Pandey, Suvidha,Thakur, Aarti,Thapar, Renu
, (2021/12/24)
A novel, facile, highly efficient and stereoselective protocol for the synthesis of cis-3-allyl-3-phenylsulfinyl-β-lactams and 3-allylidene-β-lactams from cis-3-allyl-3-phenylthio-β-lactams using Selectfluor both as an oxidizing agent and as an eliminating agent with temperature as a control parameter over the reaction outcome has been reported. The methodology is able to conquer the earlier reported shortcomings of long reaction time (24–90 hrs.) and lack of control over product ratio. The synthesized compounds will serve as important synthons for compounds of enhanced biological activity and potency.
Competitive behavior of nitrogen based axial ligands in the oxovanadium(IV)-salen catalyzed sulfoxidation of phenylmercaptoacetic acid
Kavitha, C.,Subramaniam, P.
, (2020/08/10)
The sulfoxidation of twelve phenylmercaptoacetic acids (PMAA) by H2O2 catalyzed by three oxovanadium(IV)-salen complexes, having varied substituents on PMAA and salen with regard to their position, size and inductive effect, has been performed spectrophotometrically in 100percent acetonitrile medium. Three nitrogen bases (NB), pyridine (Py), imidazole (ImH) and 1-methylimidazole (MeIm), were used as axial ligands. It has been found that the rate of sulfoxidation is not only tuned by the substituents on PMAA and salen, but it is also varied by the addition of nitrogen bases. The observed order of retardation found among the different nitrogen bases is ImH > MeIm > Py. The rate of reaction decreases with the increase in concentration of the NB axial ligands. The strongly binding ImH shows the least reactivity. Hydroperoxovanadium(V)-salen has been proposed as the sole active oxidizing species. A detailed mechanistic study reveals that the low rate constant values in the presence of the nitrogen base is due to the existence of competition of NB with H2O2 and PMAA during the formation of active species and the coordination of PMAA with active species, respectively. Both electron donating and electron withdrawing substituents on PMAA retard the sulfoxidation rate significantly. The Hammett correlation between the rate constants and substituent constants shows a non-linear concave downward curve which is explained by the existence of two different rate determining steps within the same mechanism; coordination of PMAA with the active species for electron withdrawing substituents and transfer of oxygen to PMAA for electron donating substituents. All the experimental observations are explained by proposing a suitable mechanism.
The synthesis and characterization of tetramic acid derivatives as Mdm2-p53 inhibitors
Muszak, Damian,?abuzek, Beata,Brela, Mateusz Z.,Twarda-Clapa, Aleksandra,Czub, Miroslawa,Musielak, Bogdan,Surmiak, Ewa,Holak, Tad A.
, p. 161 - 174 (2019/04/26)
We present syntheses, prediction of tautomer forms and activities of the second generation of the Mdm2-p53 inhibitors that are based on the tetramic acid scaffold. The inhibitors do not contain 6-chloroindole. Binding of these compounds to Mdm2 was checked by two orthogonal methods: the fluorescence polarization and the 1H-15N HSQC NMR titration experiments. We discovered that the 3-phenylthio-substituted tetramic acid derivatives exist in solution solely in their enol forms which is in contrast to the similar 3-aliphatic substituted derivatives. The inhibitory (Ki) and dissociation (KD) constants are in low micromolar ranges with the best binding compound 9a having KD = 2.9 μM. Furthermore, our data show that the compounds indeed bind to the p53-binding pocket of Mdm2 and do not cause dimerization of Mdm2. The current work provides solid base for further rational design of the Mdm2/p53 inhibitors.