Study of Non-Covalent Interactions Present in the Tapinarof-Ethanol System with Special Emphasis on Hydrogen-Bonding Interactions

In this study, the effect of non-covalent interactionin the tapinarof-EtOHsystems is evaluated, particularly the hydrogen-bonding interactionusing density functional theory in a gas phase. From the optimizationresults and the binding energy calculated thereafter, it is concludedthat interaction in the employed system occurs between the O-Hgroups on tapinarof and the oxygen atom of EtOH molecules existingin the vicinity of the O-H group. These interactions were concludedto be those of the weak hydrogen bonds by carrying out the reducedgradient approach and QTAIM analysis, which are basically electron-density-basedtopological analyses. The charge localization between the donor-acceptormoieties was analyzed using the NBO analysis. Using the LED analysis,the binding energy between the tapinarof and EtOH was partitionedinto different energy terms centered on a domain-based local pairnatural orbital coupled cluster method. Thus, the electronic environmentof the tapinarof-EtOH systems is evaluated.