How many conformers of the 1, 2, 3-propanetriol triacetate are present in gas phase and in aqueous solution?

Abstract We found 109 rotamers within 3 kcal from the global minimum of the triglyceride in vacuo and only 6 water-solvated rotamers within this range. Hydration restricts triacetin's conformational flexibility which is an unusual situation for small polar molecules. The lowest solvated conformation forms a system of three ring-like formations as the three carbonyl oxygens approach the hydrogen of the mid carbon of the glyceride skeleton. The structures of the global minima were subjected to geometry optimization with ab initio methods in order to validate the results.

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