Using fast scanning calorimetry to study solid-state cyclization of dipeptide L-leucyl-L-leucine

• Published in: Thermochimica acta 2020-10, Vol.692, p.178748, Article 178748
• Main Authors: Safiullina, Aisylu S., Buzyurov, Aleksey V., Ziganshina, Sufia A., Gerasimov, Alexander V., Schick, Christoph, Gorbatchuk, Valery V., Ziganshin, Marat A.
• Format: Article
• Language: English
• Subjects: 2,5-Diketopiperazines; Dipeptide; Fast scanning calorimetry; Non-isothermal kinetics; Solid-state synthesis
• ISSN: 0040-6031; 1872-762X
• DOI: 10.1016/j.tca.2020.178748

[Display omitted] •Solid-state cyclization of dipeptide was studied by fast scanning calorimetry.•Kinetic parameters of leucyl-leucine cyclization in the solid-state were estimated.•Specific heat capacity versus temperature for linear and cyclic Leu-Leu dipeptides. The possibility of using fast scanning calorimetry (FSC) to study the kinetics of the solid-state cyclization of dipeptide was demonstrated in the present work for the first time. The activation energy and Arrhenius constant of the cyclization of L-leucyl-L-leucine (Leu-Leu) were estimated. FSC data obtained at heating rates from 18,000 to 54,000 K min−1 were evaluated by non-isothermal kinetics. The dependence of the specific heat capacity cp on temperature was determined for linear and cyclic Leu-Leu dipeptides using differential scanning calorimetry (DSC) and FSC. The application of FSC allows studies of solid-state reactions for expensive substances and compounds synthesized in very small amounts.