Heptane → HCID 88467540, compound

Participants

Reaction Steps

Diphenylmethyl 7-(t-butoxycarbonylamino)-3-(2-amino-3,4-dioxo-1-cyclobutenyl)-3-cephem-4-carboxylate (400 mg, 0.712 mmol) was added to a stirred solution of p-toluenesulfonic acid monohydrate (272 mg, 1.43 mmols) in acetonitrile (1.6 mL). Stirring was continued for 0.5 hr at 22° C., at which time additional acetonitrile (1 mL) and H2O (2 drops) were added. Stirring was continued for an additional 0.5 hr at 22° C. and then for 0.33 hr at a water bath temperature of 35°-40° C. The solution was applied to a Michel-Miller HPLPLC column (22×300 mm, purchased from Ace Glass) containing Partisil Prep 40 ODS-3 (purchased from Whatman Chemical Separation Inc., Clifton, N.J.). The column was eluted with a mixture of 80% acetonitrile-20% H2O (50%) and 0.05M (pH 6.5) ammonium phosphate (50%). The appropriate fractions were combined and acetonitrile was removed on a rotary evaporator. The resulting mixture was extracted with ethyl acetate (3×). The combined extracts were washed (saturated aqueous NaCl), dried (MgSO4), and partially concentrated. Dilution with n-heptane precipitated the title compound as a yellow powder (93.6 mg, 28% yield). Analytical HPLC indicated a purity of 97 area percent.

Provenance & Evidence