Stereochemistry-dependent hydrogen bonds stabilise stacked conformations in jet-cooled cyclic dipeptides: (LD) vs. (LL) cyclo tyrosine–tyrosine
| Autor: | Nejm-Eddine Jaidane, Valeria Lepere, Ivan Alata, Anne Zehnacker, Feriel BenNasr, Ariel Pérez-Mellor |
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| Přispěvatelé: | Centre laser université Paris Sud (CLUPS), Université Paris-Sud - Paris 11 (UP11), Laboratoire des collisions atomiques et moléculaires (LCAM), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Moléculaires d'Orsay (ISMO), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), SYSIPHE, Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Dipeptide
010304 chemical physics Hydrogen bond Chemistry Stereochemistry Diastereomer Aromaticity 010402 general chemistry Ring (chemistry) Resonance (chemistry) 01 natural sciences 0104 chemical sciences 3. Good health chemistry.chemical_compound Radical ion 0103 physical sciences [CHIM]Chemical Sciences Physical and Theoretical Chemistry Conformational isomerism ComputingMilieux_MISCELLANEOUS |
| Zdroj: | Faraday Discussions Faraday Discussions, Royal Society of Chemistry, 2018, 212, pp.399-419. ⟨10.1039/c8fd00079d⟩ |
| ISSN: | 1359-6640 1364-5498 |
| DOI: | 10.1039/c8fd00079d⟩ |
| Popis: | Tyrosine-containing cyclic dipeptides based on a diketopiperazine (DKP) ring are studied under jet-cooled conditions using resonance-enhanced multi-photon ionisation (REMPI), conformer-selective IR-UV double resonance vibrational spectroscopy and quantum chemical calculations. The conformational landscape of the dipeptide containing natural L tyrosine (Tyr), namely c-LTyr–LTyr strongly differs from that of its diastereomer c-LTyr–DTyr. A similar family of conformers exists in both systems, with one aromatic ring folded on the dipeptide DKP ring and the other one extended. Weak NH⋯π and CH⋯π interactions are observed, which are slightly different in c-LTyr–LTyr and c-LTyr–DTyr. These structures are identical to those of LL and LD cyclo diphenylalanine, which only differ from c-Tyr–Tyr by the absence of hydroxyl on the benzene rings. While this is the only conformation observed for c-LTyr–DTyr, c-LTyr–LTyr exhibits an additional form stabilised by the interaction of the two hydroxyls, in which the two aromatic rings are in a stacked geometry. Stereochemical effects are still visible in the radical cation, for which one structure is observed for c-LTyr–DTyr, while the spectrum of the c-LTyr–LTyr radical cation is explained in terms of two co-existing structures. |
| Databáze: | OpenAIRE |
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