Molnupiravir (MPV) has a strong antiviral
effect. However,
there
are few existing reports on the solubility properties of this drug.
In this article, the solubility of MPV in 15 monosolvents was measured
using the gravimetric method. Among all experimental solvents, the
solubility of MPV was found to be the highest in cyclohexanone and
the lowest in ethyl formate. In alcohol solvents, the maximum solubility
was observed in s-butanol, while the minimum value
was observed in i-butanol. The solubility of MPV
increases with an increase in the temperature. Thermodynamic models
including the modified Apelblat model, λh model,
Yaws model and Abolghasem Jouyban model were chosen to fit the solubility
data in 15 monosolvents. The Abolghasem Jouyban model fitted the experimental
data best among all the selected models in 15 monosolvents, with relative
average deviation (RAD) = 0.0024. Finally, a molecular dynamics simulation,
radial distribution function (RDF) analysis, and density functional
theory (DFT) calculation were performed. The results indicated that
MPV could interact with organic solvents via van der Waals interactions,
electrostatic interactions, and hydrogen bonding. The experimental
data for MPV will provide significant guidance for the optimization
of the crystallization process.