Benzylamine → Cbz-Trp-NHBn

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Reaction Steps

The coupling procedure described above for the preparation of Cbz-Phe-Ala-NH2 was employed using 10.0 g of Cbz-Trp-OH (Sigma Chemical Company) and 4.84 mL of freshly distilled BnNH2 in dry THF to give 11.3 g (89% yield) of crystalline Cbz-Trp-NHBn. Characteristic analytical data are as follows: mp 104°-105° C.; 1H NMR (300 MHz, CDCl3) δ8.00-6.88 (m, 16H, Ar), 5.85 (br, 1H, H-α), 5.45 (br, 1H, H-N), 5.10 (s, 2H, CH2--O), 4.57-4.45 (br, H-), 4.27 (t, 6H, CH2 --N), 3.38 (dd, J=4, 14 Hz, 1H, H-β), 3.16 (dd, J=8, 14 Hz, 1H, H-β); mass spectrum (EI), m/e 427 (M+), 336 (M+ -Bn), 277 (M+ -Cbz-NH), 130 (M+ -Cbz-NH-CH-CONH-Bn), 91 (Bn+); [α]25D +7.0° (c=0.20, EtOAC).

Provenance & Evidence