compound SP307P. Same procedure as above with Trp-NHCH2Ph (120.7 mg, 0.411 mmol), N-Boc-Tyr(Bn)-Lys(Boc)-OH (246.9 mg, 0.411 mmol), EDC (87.1 mg, 0.45 mmol) and HOBt (62.1 mg, 0.46 mmol) in CH2Cl2/DMF (1.8 mL, 1/1). The crude residue was triturated with MeOH/pentane to afford a white solid (243 mg, 67%). 1H NMR (300 MHz, DMSO-d6) δ 1.2-1.61 (m, 6H, 3 CH2 Lys), 1.29 (s, 9H, (CH3)3), 1.36 (s, 9H, (CH3)3), 2.64 (m, 1H, CH2 Tyr), 2.86 (m, 3H, CH2 Lys, CH2 Tyr), 3 (dd, J=14.1 Hz, J=7 Hz, 1H, CH2 Trp), 3.14 (dd, J=14.1 Hz, J=6 Hz, 1H, CH2 Trp), 4.11 (m, 1H, CHα), 4.26 (m, 3H, CH2 (Bn Trp), CHα), 4.59 (m, 1H, CHα), 5.02 (broad s, 2H, CH2 (Bn)), 6.72 (m, 1H), 6.85-7.4 (m, 19H), 7.59 (d, J=7.6 Hz, 1H), 7.89 (d, J=7.4 Hz, 1H), 8.1 (d, J=7.4 Hz, 1H), 8.38 (m, 1H), 10.8 (s, 1H). 13C NMR (75 MHz, DMSO-d6) δ 22.4, 29.2, 32 (3 CH2 Lys), 27.8 (CH2 Trp), 28.1, 28.2 (2 (CH3)3), 36.3 (CH2 Tyr), 39.8 (CH2 Lys), 42 (CH2 (Bn) Trp), 52.4, 53.5, 55.8 (CHα Tyr, Lys, Trp), 69.1 (CH2 (Bn)), 77.3, 78 (2 C(CH3)3), 109.7, 111.2, 114.3, 118.2, 118.4, 120.8, 123.5, 126.5, 126.9, 127.3, 127.5, 127.7, 128, 128.3, 130.1, 130.2, 136, 137.2, 139 (25 aromatic C), 155.2, 155.5, 156.8 (Car-O, 2 CO carbamate), 171, 171.3, 171.6 (3 CO amide). Anal. Calcd. for C50H62N6O, 2H2O: C, 65.91; H, 7.30; N, 9.22. Found: C, 65.59; H, 7.06; N, 9.09.
