A high-pressure polymorph of chlorpropamide formed on hydrostatic compression of the α-form in saturated ethanol solution.
The crystal structure of the high-pressure polymorph (α') of an antidiabetic drug, chlorpropamide [4-chloro-N-(propylaminocarbonyl)benzenesulfonamide, C(10)H(13)ClN(2)O(3)S], which is formed at ~2.8 GPa from the α-polymorph (P2(1)2(1)2(1)) on hydrostatic compression in saturated ethanol solution, has been determined. As a result of the phase transition, the a, c and α parameters change jumpwise, whereas the changes in b parameter are continuous through the phase transition point. The high-pressure form is monoclinic (P2(1)11) and has Z' equal to 2, the two independent molecules differing in their conformations. The hydrogen bonds expand slightly in the high-pressure polymorph after the transition, and this expansion is interrelated with the changes in molecular conformations enabling a denser packing. The transition is reversible, but the crystal quality deteriorates as a result of multiple compression-decompression cycles, and a pseudomerohedral twinning accompanies the transformation.
Novosibirsk State University, REC-008, Pirogova 2, Novosibirsk 90, Russian Federation.
Yury V
YV
Seryotkin
Tatiana N
TN
Drebushchak
Elena V
EV
Boldyreva
D002747:Chlorpropamide / Q000737:chemistry*; D003460:Crystallization; D000431:Ethanol / Q000737:chemistry*; D006860:Hydrogen Bonding; D015394:Molecular Structure; D044367:Phase Transition; D011312:Pressure; D011437:Propylamines / Q000737:chemistry*; D012996:Solutions / Q000737:chemistry*; D013449:Sulfonamides / Q000737:chemistry*; D000096926:Benzenesulfonamides
D002747:Chlorpropamide; D000431:Ethanol; D011437:Propylamines; D012996:Solutions; D013449:Sulfonamides; C522878:4-chloro-N-(propylaminocarbonyl)benzenesulfonamide; D000096926:Benzenesulfonamides
chlorpropamide; high pressure; hydrogen bonds; molecular conformations; polymorphism; twinning