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Updated: Jan 25, 2026

Synthesis and Microdiffraction at Extreme Pressures and Temperatures
Published on: October 7, 2013
Completing the picture of tolazamide polymorphism under extreme conditions: a low-temperature study
Alexey Yu Fedorov1, Denis A Rychkov1, Evgeniy A Losev1
1Novosibirsk State University, Pirogova str. 2, Novosibirsk 630090, Russian Federation.
Abstract:
We present the results of an experimental and computational study of structural changes in two polymorphs of tolazamide {systematic name: 1-[(azepan-1-ylamino)carbonyl]-4-methylbenzenesulfonamide}, C14H21N3O3S, on cooling to 100 K and reverse heating. No phase transitions occurred in this temperature range. The anisotropy of the thermal expansion was different for the two polymorphs and differed from that reported previously for the hydrostatic compression. The changes in different intermolecular contacts responsible for the strain anisotropy were analysed. Relative shortening of the contacts was related directly to their initial length and reversely to the steric density around them. Increasing steric density is likely to be the driving force for the conformational ordering of the azepane ring under compression.
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