Hydrochloric Acid → HCID 14630194, compound

Participants

Reaction Steps

To a stirred solution at 0° C, of HCl.H-Glu(OBzl)-OBzl (1.82 g, 5 mmol) in DMF (35 ml), Et3N (0.7 ml) was added dropwise followed by Boc-Gly-OSu (1.5 g, 5.5 mmol). The mixture was stirrred at 0° C for 2 hr and at room temperature overnight; pH 8 was maintained by addition of a few drops of Et3N. The reaction mixture was then evaporated to a small volume and H2O was added. The precipitated oil was extracted with EtOAc and the organic phase was washed with 1 M AcOH, water, and dried (Na2SO4). Evaporation provided an oil which was purified on a Silica gel 60 column using CHCl3 :MeOH (5:1) as eluant. The pooled fractions containing (XVIII) were evaporated yielding colorless oil which failed to crystallize, 1.62 g (67%) homogeneous on tlc [α]D25 -15.0° (c 2, MeOH). Anal. Calcd for C26H32N2O7 (484.558): C, 64.45; H, 6.66; N, 5.78. Found: C, 64.23; H, 6.72; N, 5.66. Compound XVIII was also prepared from Boc-Gly-Glu(OBzl)-OH via the cesium salt procedure of Wang et al, supra.

Provenance & Evidence