Accurate kinetic measurements of the rate constants for the acidolysis of five N-acetyl-N-(4-methoxybenzyl)-alpha,alpha-trialkyl glycine cyclohexyl amides in TFA were performed at 25 degrees C and the reactions monitored by HPLC. In all cases the results were consistent with a first order behaviour with respect to the substrate. No direct correlation was obtained with these data between the rate constant values and structure, but a good correlation coefficient was obtained when a multiple regression analysis was applied by taking advantage of a Taft equation using appropriate polar and steric substituent parameters. In a plot of the values observed for log k against those calculated by this equation all five points fell very close to the line of perfect correlation. The calculated sensitivity coefficients to polar and steric contributions were used to discuss the experimental results and showed that the acidolysis were comparatively less affected by steric effects than expected.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/psc.673 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Mechanisms of the Photomechanical Response in Thin-Film Dye-Doped Glassy Polymers.
Polymers (Basel)
January 2025
Department of Physics, Washington State University, Pullman, WA 99163, USA.
This work aims to determine the mechanism of the photomechanical response of poly(Methyl methacrylate) polymer doped with the photo-isomerizable dye Disperse Red 1 using the non-isomerizable dye Disperse Orange 11 as a control to isolate photoisomerization. Samples are free-standing thin films with thickness that is small compared with the optical skin depth to assure uniform illumination and photomechanical response throughout their volume, which differentiates these studies from most others. Polarization-dependent measurements of the photomechanical stress response are used to deconvolute the contributions of angular hole burning, molecular reorientation and photothermal heating.
View Article and Find Full Text PDFMechanistic Insights into the Anticancer Potential of Methoxyflavones Analogs: A Review.
Molecules
January 2025
Preclinical Department, Faculty of Medicine & Defence Health, Universiti Pertahanan Nasional Malaysia, Kuala Lumpur 57000, Malaysia.
2-phenylchromen-4-one, commonly known as flavone, plays multifaceted roles in biological response that can be abundantly present in natural sources. The methoxy group in naturally occurring flavones promotes cytotoxic activity in various cancer cell lines by targeting protein markers, in facilitating ligand-protein binding mechanisms and activating cascading downstream signaling pathways leading to cell death. However, the lipophilic nature of these analogs is a key concern as it impacts drug membrane transfer.
View Article and Find Full Text PDFEngineering perfluoroarenes for enhanced molecular barrier effect and chirality transfer in solutions.
Chem Sci
January 2025
School of Chemistry and Chemical Engineering, Shandong University Jinan 250100 PR China
Noncovalent forces have a significant impact on photophysical properties, and the flexible employment of weak forces facilitates the design of novel luminescent materials with a variety of applications. The arene-perfluoroarene (AP) force, as one type of π-hole/π interaction, shows unique directionality, involving an electron-deficient π-hole interacting with a π-electron-rich region, facilitating precise orientation and stabilization in supramolecular structures. Here we present an amination engineering protocol to build a perfluoroarene library based on an octafluoronaphthalene skeleton with various steric and electronic properties.
View Article and Find Full Text PDFA study on indolo[3,2,1-]carbazole donor-based dye-sensitized solar cells and effects from addition of auxiliary donors.
Phys Chem Chem Phys
January 2025
Department of Physics, Assam University, Silchar-788011, India.
Density functional theory has been employed to study indolo[3,2,1-]carbazole donor-based dyes, incorporating one and two units of 2,4-dimethoxybenzene auxiliary donors. Electrostatic potential analysis highlights the dye with one auxiliary donor (D2) as having the highest charge-donating capability. Structural analysis shows that auxiliary donors enhance planarity, reduce steric hindrance, and improve π-conjugation.
View Article and Find Full Text PDFNoncovalent carbon bonding (C-bonding), a recently explored σ-hole interaction, has primarily been characterized through X-ray structural and computational studies. Evidence of C-bonds in solution is scarce, especially in highly polar solvents like DMSO where solvation effects typically overshadow weak non-covalent interactions. In this work, we present three novel spiroisatin-based -acyl hydrazones (1-3) in which C-bonds play a critical role in stabilizing the conformation in solution.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!