1145-32-0Relevant articles and documents
Reactivity of Tyrosyl–Proline toward Benzoylation in Aqueous 1,4-Dioxane
Khachatryan, D. S.,Kochetova, L. B.,Kustova, T. P.,Lokteva, I. I.
, (2020)
Abstract: The kinetics of the reaction of L-tyrosyl-L-proline (Tyr–Pro) with di- andtrinitrophenyl benzoates in aqueous 1,4-dioxane (40 wt percent of water) were studiedin the temperature range 298–313 K. The reaction rate constant k298 was fou
Direct 3-Acylation of Indolizines by Carboxylic Acids for the Practical Synthesis of Red Light-Releasable Caged Carboxylic Acids
Watanabe, Kenji,Terao, Nodoka,Niwa, Takashi,Hosoya, Takamitsu
, p. 11822 - 11834 (2021/07/31)
To enhance the practicality of photouncaging system using 3-acyl-2-methoxyindolizines, direct acylation of indolizines with carboxylic acids was developed using condensation reagents, generally used for peptide coupling. This method allowed for caging a broad range of carboxylic acids with indolizines. The method enabled a facile synthesis of water-soluble caged bioactive carboxylic acids having an intramolecular photosensitizer. The efficient release of carboxylic acids from the synthesized caged compounds upon red light irradiation was confirmed in neutral buffered solutions.
Kinetic study on nucleophilic displacement reactions of 2-chloro-4-nitrophenyl x-substituted-benzoates with primary amines: Reaction mechanism and origin of the a-effect
Um, Tae-Il,Kim, Min-Young,Kim, Tae-Eun,Um, Ik-Hwan
, p. 436 - 440 (2014/03/21)
Second-order rate constants for aminolysis of 2-chloro-4-nitrophenyl X-substituted-benzoates (1a-h) have been measured spectrophotometrically in 80 mol % H2O/20 mol % DMSO at 25.0 °C. The Bronsted-type plot for the reactions of 2-chloro-4-nitrophenyl benzoate (1d) with a series of primary amines curves downward, which has been taken as evidence for a stepwise mechanism with a change in rate-determining step (RDS). The Hammett plots for the reactions of 1a-h with hydrazine and glycylglycine are nonlinear while the Yukawa- Tsuno plots exhibit excellent linearity with ρX = 1.22-1.35 and r = 0.57-0.59, indicating that the nonlinear Hammett plots are not due to a change in RDS but are caused by stabilization of substrates possessing an electron-donating group (EDG) through resonance interactions between the EDG and C=O bond of the substrates. The α-effect exhibited by hydrazine increases as the substituent X changes from a strong EDG to a strong electron-withdrawing group (EWG). It has been concluded that destabilization of hydrazine through the electronic repulsion between the adjacent nonbonding electrons is not solely responsible for the substituent dependent α-effect but stabilization of the transition state is also a plausible origin of the α-effect.
