The guanidiniocarbonylpyrrole–fluorophore conjugates as theragnostic tools for dipeptidyl peptidase III monitoring and inhibition

Triarylborane Dyes as a Novel Non-Covalent and Non-Inhibitive Fluorimetric Markers for DPP III Enzyme

“…We also performed a single injection ITC experiment under comparable conditions, which Thus, establishing the strong interaction of 1 and 2 with BSA, a protein known to be a small-molecule carrier in the blood, the question arose whether 1 and 2 can interact with enzymes. For that purpose, we have chosen one type of peptidase enzyme, human DPP III (hDPP III), for which we previously reported several types of fluorescent markers [13,14], which also showed promising inhibitory activity of the enzyme action. As hDPP III could eventually cleave the peptide bond in 2, we first performed fluorimetric titrations with mutant hDPP III-E451A, which due to its mutation at the active site, cannot cleave peptide bonds [11].…”

“…TLC was carried out on TLC Silica gel 60 F254 plastic sheets and a preparative thick layer (2 mm) chromatography was done on Merck 60 F254 plates (Merck KGaA, Darmstadt, Germany). NMR spectra were recorded on Bruker AV600 and AV300 MHz spectrometers operating at 150.92 or 75.47 MHz for 13 C and 600.13 or 300.13 MHz for 1 H using DMSO-d 6 as the solvent and internal reference. High-resolution mass spectra (HRMS) were obtained using a Thermo Fisher Scientific Exactive Plus Orbitrap MS System.…”

“…Parameterisation, energy minimization, and molecular dynamics (MD) simulations of the complexes between compound 2 and DPP III, as well as between 2 and the preferred synthetic substrate of DPP III Arg-Arg-2-naphthylamide (RR-2-NA), and the product of its hydrolysis 2NA were performed using the AMBER16 suite of programs [39]. The solutes were prepared using the AMBER16 utility program tLeap wherein the small molecules and DPP III were parametrized within general AMBER gaff [40] and ff14SB [41] force fields, respectively, wherein hybrid bonded-non bonded parameters were used for the zinc ion [42] (for details of the parametrization procedure, see our previous work [6,13]). Initial 2-Arg2 2NA and 2-2NA complexes were prepared in PyMOL (The PyMOL Molecular Graphics System, Version 1.7 SchroÈdinger, LLC, New York, NY, USA), while the protein complexes with 2, DPP III-2 were prepared using the DPP III-tynorphine complex (pdb code: 3T6B) as a template.…”

Fluorimetric and CD Recognition between Various ds-DNA/RNA Depends on a Cyanine Connectivity in Cyanine-guanidiniocarbonyl-pyrrole Conjugate

“…The 2 was prepared as shown on Scheme 2 , starting from the corresponding cyanine-amino acids ( Cy-aa ) [ 19 ] and guanidiniocarbonyl-pyrrole ( GCP ) [ 10 , 11 , 12 ], following a similar procedure used previously for the preparation of its analog 1 [ 18 ]. Namely, the reaction mixture of Cy-amino acid and GCP in acetonitrile with O-(1H-6-Chlorobenzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HCTU) and Et 3 N was left stirring at room temperature under argon for three days.…”

“…A larger volume of “Br” is likely to block intercalation of cyanine moiety between DNA/RNA base pairs, thus directing small molecule to the DNA or RNA grooves, which could result in the high sensitivity to binding site properties (namely, grooves of various ds-DNA or ds-RNA differ considerably—see Table S1, Supplementary Materials ). Conjugate 1 was previously tested for inhibitor properties of dipeptidyl peptidase III (DPP III) [ 18 ].…”