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Updated: Jun 23, 2026

Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
Rapid conversion of API hydrates to anhydrous forms in aqueous media
Rositza I Petrova1, Andrey Peresypkin, Christopher J Mortko
1Merck & Co., Inc, RY818-B112, P.O. Box 2000, Rahway, New Jersey 07065, USA. rositza_petrova@merck.com
Abstract:
Three anhydrous polymorphs, a monohydrate and a dihydrate of an active pharmaceutical ingredient, N-{[(5S)-3-(4-{6-[(1R,5S)-6-cyano-3-oxabicyclo[3.1.0]hex-6-yl]pyridin-3-yl}phenyl)-2-oxo-1,3-oxazolidin-5-yl]methyl}acetamide (Compound 1), have been crystallized and characterized. Slurry experiments and thermal data have been used to determine their relative thermodynamic stability. The hydrates of Compound 1 were found to be less stable than the most stable anhydrous Form I and converted into Form I in water within 15 min. The rate of conversion in a dry state was found to depend on the relative humidity (RH) and was highest at the two RH extremes examined, 5% and 97.5% RH.
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