HOBt-6-carboxamidomethyl polystyrene; dicyclohexyl-carbodiimide 1.) CH2Cl2, RT, 6 h, 2.) CHCl3, RT, 5 h; Yield given. Multistep reaction;

1: 99 percent / Et3N; (benzotriazol-1-yloxy)tris(dimethylamino)phosphonium*PF6 / tetrahydrofuran / 8 h / 0 - 20 °C 2: AcCl; MeOH / 4 h / 0 - 20 °C View Scheme

4-methyl-morpholine; isobutyl chloroformate 1.) CH2Cl2, 0 deg C, 30 min., 2.) 0 deg C, 30 min., r.t., 2 h; Yield given. Multistep reaction;

1: C16H22NO4PolS With 3-methyl-phenol; trifluoroacetic acid 0.25 h; Automated synthesizersolid phase reaction; 2: N-tert-butoxycarbonyl-O-benzyl-L-serine With 1-methyl-pyrrolidin-2-one; benzotriazol-1-ol; diisopropyl-carbodiimide 1 h; Automated synthesizersolid phase reaction; 3: BOC-glycine; N-tert-butoxycarbonyl-L-alanine; N-tert-butoxycarbonyl-L-phenylalanine; N-Boc-L-threonine benzyl ether; BOC-S-4-methoxybenzyl-L-cysteine; N6-[[(2-Chlorophenyl)methoxy]carbonyl]-N2-[t-butyloxycarbonyl]-L-lysine; N-BOC-D-tryptophan; Boc-Asn(Xan)-OH Further stages;

1: NMM / dimethylformamide / 0.17 h / -15 °C 2: NMM / dimethylformamide / 20 h / -20 °C 3: 90 percent / 1.5 N HCl/AcOH 4: 97 percent / HOBt*H2O, NEt3 / dimethylformamide / 23 h 5: 95 percent / 1.5 N HCl/AcOH / 1 h 6: 90 percent / HOBt*H2O, NEt3, DCC / dimethylformamide / a) -5 deg C to 0 deg C, 1 h, b) 20 deg C, 24 h 7: 86 percent / 0.5 M NaOH / acetone / 1.5 h View Scheme

1: 70 percent / NMM, IBCF / dimethylformamide / -15 °C 2: 85 percent / 1N NaOH / dioxane; methanol / 0 deg C, 5 h, RT 3: 54.6 percent / IBCF, NMMole / dimethylformamide / -20 °C 4: TFA, anisole / CH2Cl2 / 1 h / 0 °C 5: 55 percent View Scheme

sulfuric acid; sodium hydrogencarbonate in diethyl ether; water; ethyl acetate; acetonitrile

1: 70 percent / NMM, IBCF / dimethylformamide / -15 °C 2: 85 percent / 1N NaOH / dioxane; methanol / 0 deg C, 5 h, RT 3: 54.6 percent / IBCF, NMMole / dimethylformamide / -20 °C 4: TFA, anisole / CH2Cl2 / 1 h / 0 °C View Scheme

1: N-hydroxybenzotriazole, triethylamine, dicyclohexylcarbodiimide / dimethylformamide 2: HCl, acetic acid / various solvent(s) / 1.5 h 3: N-hydroxybenzotriazole, triethylamine, dicyclohexylcarbodiimide / dimethylformamide 4: NH3 / methanol 5: HCl, acetic acid / various solvent(s) View Scheme

1: 92 percent / Et3N, DCC / CH2Cl2 / 0 - 20 °C 2: 100 percent / HCl / ethyl acetate / 2 h / 0 °C View Scheme