, 10 mmol) or microwave protocol (0.25 mmol). The completed peptide was cleaved from the resin by treatment with the water/TIS/TFA (3:4:148 v/v) for 4 h at room temperature. The solid support was removed by filtration, the filtrate concentrated under reduced pressure, and aPvd2 precipitated from diethyl ether. All these steps were repeated 7 times, Sasrin ® was obtained and the 3,4dihydroxyphenylacetic acid (DOPAC) was double coupled using a standard FastMoc ®, vol.538

H. Nmr, CHa), 56.1 (CHa, 400 MHz, MeOD4), d (ppm): 6.77 (d, J ¼ 1.98 Hz, 1H Ar ), 6.73 (d, J ¼ 8.03 Hz, 1H Ar ), 6.63 (dd, J ¼ 1.98, 8.03 Hz, 1H Ar ), 4.47e4.43 (m, 3H), 4.40e4.20 (m, 7H), 4.00e3.81 (m, 6H), 3.48 (s, 2H), 3.12 (t, J ¼ 7.00 Hz, 2H), 2.92 (t, J ¼ 7.28 Hz, 2H), 2.50e2.41 (m, 4H), 2.25e2.15 (m, 2H), 2.06e1.95 (m, 2H), 1.95e1.85 (m, 2H), 1.85e1.70 (m, 2H), 1.70e1.55 (m, 4H), 1.55e1.40 (m, 2H), 1.26e1.20 (m, 6H, CH 3 ). 13 C NMR (100 MHz, MeOD4), d (ppm): 175.4 (COOH, Glu), vol.175

, (tBu)-Sasrin ® was cleaved from the resin and side chain deprotected by treatment with a mixture of water/TIS/TFA (3:4:148 v/v) for 4 h at room temperature. The solid support was removed by filtration, the corresponding filtrate concentrated under reduced pressure, and aPvd3 precipitated from diethyl ether. All these steps were repeated 3 times. After reversephase chromatography purification and lyophilisation the peptide, Synthesis of aPvd3 126.60 mg (0.10 mmol) of Fmoc-L-Thr(tBu)-Sasrin ® were used for the synthesis of aPvd3. The peptide Gly-D-Ser(tBu)-L-Arg(Pbf)-DSer(tBu)-L-Lys(ivDde)-L-Lys(Boc)-L-Lys(ivDde)-L-Thr(tBu)-LThr(tBu)-Sasrin ® was obtained using a standard FastMoc ®

, 3% analytical purity). The composition of aPvd3 was verified by spectrometric analysis, HPLC: 20.9 min (98

, 4 (b5 ion, DOPAC-Gly-SerArg-Ser-Lys(DOPAC)), 944.4 (b6 ion, DOPAC-Gly-Ser-Arg-SerLys(DOPAC)-Lys), 1222.6 (b7 ion, DOPAC-Gly-Ser-Arg-SerLys(DOPAC)-Lys-Lys(DOPAC)), 1323.6 (b8 ion, DOPAC-Gly-Ser-ArgSer-Lys(DOPAC)-Lys-Lys(DOPAC)-Thr). The ions y'' are represented by the fragments at 1235.6 (y''8 ion, Ser-Arg-Ser-Lys(DOPAC)-LysLys(DOPAC)-Thr-Thr), 1148.6 (y''7 ion, Arg-Ser-Lys(DOPAC)-LysLys(DOPAC)-Thr-Thr), 992.5 (y''6 ion, The fragmentation of aPvd3 by mass spectra (MS/MS) shows the presence of the ions N-terminal side at 208.1 (b1 ion, vol.538

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