Isoenergetic Polymorphism: The Puzzle of Tolazamide as a Case Study.
In the present case study of tolazamide we illustrate how many seemingly contradictory results that have been obtained from experimental observations and theoretical calculations can finally start forming a consistent picture: a "puzzle put together". For many years, tolazamide was considered to have no polymorphs. This made this drug substance unique among the large family of sulfonylureas, which was known to be significantly more prone to polymorphism than many other organic compounds. The present work employs a broad and in-depth analysis that includes the use of optical microscopy, single-crystal and powder X-ray diffraction, IR and Raman spectroscopies, DSC, semiempirical PIXEL calculations and DFT of three polymorphs of tolazamide. This case study shows how the polymorphs of a molecular crystal can be overlooked even if discovered serendipitously on one of numerous crystallizations, and how very different molecular packings can be practically isoenergetic but still crystallize quite selectively and transform one into another irreversibly upon heating.
Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze str., 630128 Novosibirsk (Russian Federation), Fax: (+7) 383-363-41-32. eboldyreva@yahoo.com.|Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation). eboldyreva@yahoo.com.
Elena V
EV
Boldyreva
Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze str., 630128 Novosibirsk (Russian Federation), Fax: (+7) 383-363-41-32.|Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation).
Sergey G
SG
Arkhipov
Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze str., 630128 Novosibirsk (Russian Federation), Fax: (+7) 383-363-41-32.|Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation).
Tatiana N
TN
Drebushchak
Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation).|Institute of Geology and Mineralogy, 3 Koptyuga pr., 630090 Novosibirsk (Russian Federation).
Valeri A
VA
Drebushchak
Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze str., 630128 Novosibirsk (Russian Federation), Fax: (+7) 383-363-41-32.|Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation).
Evgeniy A
EA
Losev
Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze str., 630128 Novosibirsk (Russian Federation), Fax: (+7) 383-363-41-32.|Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation).
Alexander A
AA
Matvienko
Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze str., 630128 Novosibirsk (Russian Federation), Fax: (+7) 383-363-41-32.|Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation).
Vasily S
VS
Minkov
Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze str., 630128 Novosibirsk (Russian Federation), Fax: (+7) 383-363-41-32.|Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation).
Denis A
DA
Rychkov
Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze str., 630128 Novosibirsk (Russian Federation), Fax: (+7) 383-363-41-32.|Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation).|Institute of Geology and Mineralogy, 3 Koptyuga pr., 630090 Novosibirsk (Russian Federation).
Yurii V
YV
Seryotkin
National Institute of Chemistry, 19 Hajdrihova str., 1000 Ljubljana (Slovenia).
Jernej
J
Stare
Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze str., 630128 Novosibirsk (Russian Federation), Fax: (+7) 383-363-41-32.|Novosibirsk State University, 2 Pirogov str., 630090 Novosibirsk (Russian Federation).
Boris A
BA
Zakharov
X-ray diffraction; calorimetry; crystal growth; density functional calculations; polymorphism