All reagents and chemicals were purchased from Merck (Milan, Italy) without further purification, except for the Rink amide linker and the 2-chlorotrityl chloride resin that were obtained from Iris Biotech GmbH (Marktredwitz, Germany). An in-line Millipore RiOs/Origin system provided MilliQ water with a resistivity higher than 18 M Ω cm. LC-MS analyses were performed on an Agilent 6120 singlequadrupole system. was obtained from. 1H-NMR and 13C-NMR spectra were recorded at 400 MHz and 100 MHz, respectively, using a 400 MHz Varian Innova Instrument, with chemical shift reported as ppm.