Conformations of n -alkyl-α/β- d -glucopyranoside surfactants: Impact on molecular properties

Abstract

Sugar-based surfactants are amphiphilic compounds bearing a head group derived from sugar. Such surfactants represent a good alternative to petroleum-based surfactants, because they can be prepared from bio-products and generally have a low toxicity. The conformational flexibility of sugars is well known and since they can form competitive intramolecular hydrogen bonding-like interactions, the most stable conformations are often non-trivial. Calculating molecular descriptors in the context of Quantitative Structure-Property Relationship (QSPR) studies require relevant conformations. To find such conformations and then develop QSPR models, in this study, we carried out a conformational analysis of two anomers, octyl α-D-glucopyranoside and octyl β-D-glucopyranoside, to exhibit the main conformational parameters of glucopyranosides and their influence on some quantum chemical molecular descriptors that could be used in QSPR models of surfactants. From a starting set of 26 conformations for each anomer, optimized at B3LYP/6-31+G(d,p) level of Density Functional Theory, three most significant conformations, common for both glucopyranosides, generated by changing a single dihedral angle, were highlighted as the most significant conformations. The influence of solvent modeled by an implicit solvation model on conformations was discussed. Moreover, the influence of conformations on calculated molecular properties (partial charges, polarisability, and dipole moment) was discussed, for n-alkyl α/β-D-glucopyranosides. It was shown that for the studied alkyl glucosides, 2 the dipole moment is influenced by the choice of conformations, but that the polarisability and the partial charges are less so.

New QSPR Models to Predict the Critical Micelle Concentration of Sugar-Based Surfactants

“…To further study the specific character of S-linked surfactants, we analyzed partial charges on the linker and along the chain, as in a previous study 81 Table 2).…”

Anticipating Dissolution Issues of Sugar‐Based Surfactants through a Decision Tree Approach

“…Frequency calculations were also performed at the same level of theory to ensure that the conformation well corresponds to a local minimum on the potential energy surface. This level of calculation has been successfully used in previous works (Gaudin et al, ) and already used for the development of QSPR models for other properties (Gaudin et al, , ) for this class of sugar‐based surfactants.…”

Synthesis of ultra‐high concentration of salt‐resistant polyacrylamide

“…More generally, glucose has a circular rigid structure and the hydroxyl groups on the molecules form hydrogen bonds, and it can form complexes with cations. [19][20][21] This is great value in the study of salt resistance of polyacrylamide.…”

“…It has low toxicity and is easy to biodegrade, which is very attractive for environmental protection. More generally, glucose has a circular rigid structure and the hydroxyl groups on the molecules form hydrogen bonds, and it can form complexes with cations 19‐21 . This is great value in the study of salt resistance of polyacrylamide.…”