Luna c18 2 hst column

Starting materials and solvents were purchased from commercial suppliers (Iris Biotech, Sigma-Aldrich, and Merck) and were used without further purification. H-Rink-Amide ChemMatrix resin (loading 0.52 mmol/g, 0.05 mmol) was purchased from PCAS BioMatrix Inc., QC, Canada. Preparative HPLC was performed by using a Phenomenex Luna C18 (2) column (250 mm × 21.2 mm; 5 μm particle size) on a Shimadzu Prominence system using an aqueous MeCN gradient with 0.1% TFA added (eluent A: 5:95 MeCN - H₂O with 0.1% TFA added; eluent B: 95:5 MeCN - H₂O with 0.1% TFA added). Analytical UHPLC was performed by using a Phenomenex Luna C18 (2) HST column (100 mm × 3.0 mm; 2.5 μm particle size) on a Shimadzu Prominence and Shimadzu Nexera system by using the above eluents A and B. All tested compounds had a purity of at least 95%. HRMS spectra were obtained by using a Bruker MicrOTOF-Q II Quadrupole MS detector.

Water was filtered by using an Evoqua LaboStar PRO TWF Ultra Pure Water System prior to use in high-performance liquid chromatography (HPLC). The retention time for each peptidomimetic was determined by analytical HPLC using a Phenomenex Luna C18(2) HST column (100 mm × 3 mm; particle size: 2.5 μm; pore size: 100 Å) on a Shimadzu Prominence and Shimadzu Nexera system using an aqueous MeCN gradient with 0.1% trifluoroacetic acid (TFA) added (eluent A: 5:95 MeCN–H₂O + 0.1% TFA; eluent B: 95:5 MeCN–H₂O + 0.1% TFA); a flow rate of 0.5 mL/min was used. For the elution of peptidomimetics, a linear gradient of 0% to 60% B over 10 min was used with UV detection at λ = 220 nm. The percentage MeCN at peak elution was calculated from the retention time (t_R) by using the following formula: