These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Conformational polymorphs of isobutyl-6-amino-5-cyano-2-methyl-4-phenyl-4H-pyran-3-carboxylate: spectroscopic, structural and DFT approach.
    Author: Prasad AA, Kumar CU, Prakasam BA, Meenakshisundaram SP.
    Journal: Acta Crystallogr B Struct Sci Cryst Eng Mater; 2016 Jun 01; 72(Pt 3):301-9. PubMed ID: 27240761.
    Abstract:
    The crystal structure of a new crystalline phase, polymorph (II) of isobutyl-6-amino-5-cyano-2-methyl-4-phenyl-4H-pyran-3-carboxylate, was accurately determined by single-crystal X-ray diffraction analysis providing a clean identification of polymorphic forms. Comparison with a known phase, referred to as polymorph (I), reveals the type of supramolecular assembly. Inter- and intramolecular hydrogen-bonding interactions exhibit various supramolecular architectures in crystal packing and these variations confirm well the polymorphism in isobutyl-6-amino-5-cyano-2-methyl-4-phenyl-4H-pyran-3-carboxylate (IAPC) crystal structure. Crystal cohesion is achieved by N-H...N, N-H...O and C-H...H-C interactions, responsible for the formation and strengthening of the supramolecular assembly. The objective of this investigation is to study crystalline forms which can offer enhanced physicochemical properties, and also to recognize the molecular orientations between such forms. The conformational polymorphs of IAPC were compared spectroscopically by FT-IR and FT-Raman. The bulk phases were studied by X-ray powder diffraction patterns. External morphology was investigated using scanning electron microscopic images. The molecular interactions were quantified using Hirshfeld surface and fingerprint analysis. Density functional theory (DFT) computations were used to optimize the structure. The optimized structure is further subjected to an analysis of Mulliken population, natural population and electrostatic potential.
    [Abstract] [Full Text] [Related] [New Search]