ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Publication Date: 2015-06-14
    Description: The title compounds, 6-(2-hydroxybenzyl)-5H-thiazolo[3,2-a]pyrimidin-5-one, C13H8N2O3S, (1), and 6-(2-hydroxybenzyl)-3-methyl-5H-thiazolo[3,2-a]pyrimidin-5-one, C14H10N2O3S, (2), were synthesized when a chromone-3-carboxylic acid, activated with (benzotriazol-1-yloxy)tripyrrolidinylphosphonium hexafluoridophosphate (PyBOP), was reacted with a primary heteromamine. Instead of the expected amidation, the unusual title thiazolopyrimidine-5-one derivatives were obtained serendipitously and a mechanism of formation is proposed. Both compounds present an intramolecular O—H...O hydrogen bond, which generates an S(6) ring. The dihedral angles between the heterocyclic moiety and the 2-hydroxybenzoyl ring are 55.22 (5) and 46.83 (6)° for (1) and (2), respectively. In the crystals, the molecules are linked by weak C—H...O hydrogen bonds and π–π stacking interactions.
    Keywords: crystal structurethiazoleconformationsupramolecular structurehydrogen bondingπ–π stacking interactions
    Electronic ISSN: 1600-5368
    Topics: Chemistry and Pharmacology , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2014-12-21
    Description: Four N-(4-halophenyl)-4-oxo-4H-chromene-3-carboxamides (halo = F, Cl, Br and I), N-(4-fluorophenyl)-4-oxo-4H-chromene-3-carboxamide, C16H10FNO3, N-(4-chlorophenyl)-4-oxo-4H-chromene-3-carboxamide, C16H10ClNO3, N-(4-bromophenyl)-4-oxo-4H-chromene-3-carboxamide, C16H10BrNO3, N-(4-iodophenyl)-4-oxo-4H-chromene-3-carboxamide, C16H10INO3, have been structurally characterized. The molecules are essentially planar and each exhibits an anti conformation with respect to the C—N rotamer of the amide and a cis geometry with respect to the relative positions of the Carom—Carom bond of the chromone ring and the carbonyl group of the amide. The structures each exhibit an intramolecular hydrogen-bonding network comprising an N—H...O hydrogen bond between the amide N atom and the O atom of the carbonyl group of the pyrone ring, forming an S(6) ring, and a weak Carom—H...O interaction with the O atom of the carbonyl group of the amide as acceptor, which forms another S(6) ring. All four compounds have the same supramolecular structure, consisting of R22(13) rings that are propagated along the a-axis direction by unit translation. There is π–π stacking involving inversion-related molecules in each structure.
    Keywords: crystal structuredrug designchromonesconformationsupramolecular structure
    Electronic ISSN: 1600-5368
    Topics: Chemistry and Pharmacology , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2017-07-13
    Description: Chromone derivatives have been extensively studied recently because of to their promising biological activities. The new title chromone–thiazole hybrid presented here, C14H10N2O3S, is a candidate as a selective ligand for adenosine receptors. The compound has been synthesized and characterized by the usual spectroscopic means (NMR and EM/IE) and its structure elucidated by X-ray crystallography, which revealed the presence of packing polymorphism. The two polymorphs (one with space group P21/n and one with P21/c) show slightly different conformations and the major change induced by crystallization regards the intramolecular contacts defining the supramolecular structure. Those differences been highlighted by Hirshfeld surface analysis mapped over dnorm and ESP.
    Keywords: crystal structuredrug designchromonesconformationsupramolecular structure
    Electronic ISSN: 1600-5368
    Topics: Chemistry and Pharmacology , Geosciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...