Z-Glu(OtBu)-Lys(Boc)-Lys(Boc)-Glu(OtBu)-Val-Val-Glu(OtBu)-Glu(OtBu)-Ala-Glu(OtBu)-Asn-OtBu → H-Glu(OtBu)-Lys(Boc)-Lys(Boc)-Glu(OtBu)-Val-Val-Glu(OtBu)-Glu(OtBu)-Ala-Glu(OtBu)-Asn-OtBu

Participants

Reaction Steps

A solution of Z-Glu(OtBu)-Lys(Boc)-Lys(Boc)-Glu(OtBu)-Val-Val-Glu(OtBu)-Glu(OtBu)-Ala-Glu(OtBu)-Asn-OtBu (45.0 g, 23 mmol) in TFE (1.1 L) containing 10% Pd-BaSO4 (15 g) was hydrogenated in a Vibromixer apparatus for 3 h. The reaction mixture was filtered through celite which was washed with TFE (3×100 mL). The combined filtrate was evaporated to dryness and taken up in DMF:DMSO (1300 mL:650 mL) for use in the next stage of synthesis. A portion of the residue was precipitated from TFE-H2O, filtered and dried in vacuo; mp 326°-327°; [α]D25 -17.65° (c 1, DMSO); Rf 0.73 (n-BuOH:AcOH:EtOAc:H2O; 1-1-1-1). Anal. calc. for C88H154N14O27.H2O (1876.27): C, 56.33; H, 8.49; N, 10.45. Found: C, 56.40; H, 8.69; N, 10.55.

Provenance & Evidence