steric effect

steric effect

[′ster·ik i‚fekt]
(physical chemistry)
The influence of the spatial configuration of reacting substances upon the rate, nature, and extent of reaction.
References in periodicals archive ?
Essentially, the steric effect relates to the spatial arrangement of atoms in the molecule, especially as the arrangement impacts a chemical reaction.
SAR studies with refrence to analgesia suggested that the opiod receptors were responsible for antinociceptive, hence in the series of substituted piperidine analogues, the nature of receptor binding with the structure of whole molecule describes analgesic response and hence the strength and also the duration of action may be influenced only by the steric effect.
With the increase of the EO units, the esterification rate of dodecyl alcohol polyoxyethylene ethers decreased, which could mainly be due to steric effect.
The implications are rather large because the cornerstone of our understanding of the structure of molecules is the steric effect," says Goodman.
On the other hand decrease in activity in case of octyl and nonyl ester substituent may be due to steric effect as enzyme cannot favorably accommodate these bulkier analogs.
The chelating of DNA with metal complexes will lead to the inhibition of DNA synthesis in cancer cells and microbes which result to apoptosis of the cell, this could be probably due to electronic effect, lipophilicitym steric effect or could be to the hydrophobic behaviors to the molecule of the complex.
The ionic nature of the polymer results in the electrostatic repulsion between nanoparticles while the long polymer chain simultaneously keeps the nanoparticles away from each other by steric effect.
17) This relayed steric effect would account for increased activation energy of the transition state; hence, it may justify the observed hydrolysis rate.
Steric effect played an important role in complex formation and achieving good ees as the enantiomeric excess of 1-phenylethanol obtained was maximum 81% for 8 (Entry 5 table 1), which helped us to access structure of the ligands in easy way.
At the same time, larger molecule could be obtained after derivatization, and the steric effect could enhance adsorption with CSP to improve chiral recognition.