Jet-cooled laser spectroscopy and solid-state vibrational circular dichroism of the cyclo-(Tyr-Phe) diketopiperazine dipeptide
نویسندگان
چکیده
The structures of the diastereomer diketopiperazine dipeptides cyclo(LTyr-LPhe) and cyclo-(DTyr-LPhe) are studied in gas phase using resonance-enhanced two-photon ionization, IR/UV double resonance spectroscopy quantum chemical calculation. Both diastereomers exhibit two conformations, with tyrosine ring folded over DKP phenylalanine extended outwards, or vice versa. differ only slightly by nature weak CH···π NH···π interactions. crystal structure is determined X-ray crystallography composed monomers ring. vibrational circular dichroism spectrum interpreted existence dimers solid state. Quantum calculation shed light on structural modifications between
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ژورنال
عنوان ژورنال: Journal of Molecular Structure
سال: 2022
ISSN: ['0022-2860', '1872-8014']
DOI: https://doi.org/10.1016/j.molstruc.2022.133059