Structures of the triclinic and monoclinic modifications of (2-oxo-1-pyrrolidinyl)acetamide

Abstract

C6H10N202 crystallizes in a triclinic (T) and a monoclinic (M) modification. T has space group Pi with a = 6.403 (3), b = 6.618 (4), c = 8.556 (6) Least-squares refinement gave R(T) = 5.8% for 2499 and R(M) = 6.4% for 2435 independent reflections 0567-7408/82/102600-06501.00

Pharmaceutical Co-Crystals

“…124,125 Four polymorphic forms of 2 have been deposited in the CSD. [126][127][128][129] Two forms, a triclinic and a monoclinic modification, crystallize via III, while the other two are monoclinic forms, crystallizes in a catemeric fashion (Fig. 6).…”

Phenomenology of Polymorphism, III:p,TDiagram and Stability of Piracetam Polymorphs

“…If slope 5 Ͼ slope 7, curve The molecular volumes of phases II and III (Table 1) 5, which also crosses this triple point, cannot be directed are taken from Ref. (10) because the lattice parameter toward triple point f (II-III-v) of Fig. 4, that has been values have been obtained with the same apparatus, and proved to be positioned at high temperature.…”

Prediction of the crystal structures of axitinib, a polymorphic pharmaceutical molecule

“…Thus, there are emerging attempts (Day et al, 2003;Karamertzanis et al, 2008;van Eijck, 2001;Vasileiadis, 2013) to take some account of entropic contributions. A further approximation is usually made to neglect the pV term, as this is very small (of the order of J mol À 1 ) at low pressures, only becoming practically important at pressures of the order of GPa (Admiraal et al, 1982;Allan et al, 2002;Paliwoda et al, 2012).…”