Azide → HCID 131711193, compound

Participants

Reaction Conditions

Reaction Steps

Boc-Leu-Phe-OH (XVI) (0.53 g, 1.4 mmol) was deblocked with 4 N HCl/THF (17.5 ml) and worked up as in Example 9 to yield the white crystalline salt. Boc-Ser(Bzl)-Gln-Thr(Bzl)-Pro-Leu-Val-Thr(Bzl)-NHNH2 (XV) (0.79 g, 0.7 mmol) in DMF (10 ml) was converted into the azide by treatment with 2.8 N HCl/THF (1.25 ml) and i-amylnitrite (0.14 ml) at -20° C for 25 min. The temperature was lowered to -30° C, Et3N (0.49 ml) was added followed by a pre-cooled mixture of the hydrochloride salt of compound (XVI) which was pretreated with Et3N. The mixture was stirred for 1.5 hr at -15° C and for 4 days at 4° C. It was acidified with glacial AcOH, evaporated to a smaller volume, and treated with 1 M AcOH. The precipitated solid was filtered and washed with H2O. The crude product (0.92 g) mp 194°- 196.5° C, after trituration with EtOAc, was recrystallized from hot MeOH to provide (XVII) in fine crystals, 0.51 g (53%); mp 205°-207° C; [α]D25 -20.1° (C 1, DMF). Anal. Calcd for C73H102N10O16 (1375.70): C, 63.73; H, 7.47; N, 10.18. Found: C, 63.26; H, 7.43; N, 10.23. Amino Acid Analysis (6 N HCl-phenol, 100° C, 24 hr): Thr2.00, Ser0.91, Glu1.03, Pro1.05, Val0.99, Leu2.08, Phe1.00.

Provenance & Evidence