Abstract
7-Aminocephalosporanic acid(7-ACA) was reacted with diphenyldiazomethane(DPM) to get diphenylmethyl 7-$\beta$-(O-ethylphthalimidomethylphosphony1)-3-acetoxymethyl-3-cephem-4-carboxylate. Diethyl phthalimidomethylphosphonate was chloridated with a slight excess of phosphorus pentachloride to the O-ethyl phthalimidoalkylphosphonochloridate. Previously unreported two compounds, diphenylmethy1 -7-$\beta$-(O-ethylphthalimidomethylphosphony1)-3-acetoxymethyl-3-cephem-4-carboxylate and diphenylmethyl-7-$\beta$-[O-ethylphthalimidoethylphosphonyl]-3-acetoxymethyl-3-cephem-4-carboxylate were synthesized by cupling reaction of DPM 7-ACA and O-ethyl phthalimidoalkylphosphonochloridate. All of the compounds including starting materials and reaction intermediates were characterized by $^1H$ NMR and FT-IR spectroscopy.
Phthalic anhydride를 출발물질로 halogenation, phosphorylation하여 diethyl phthalimidoalkylphosphonate를 합성하였다. 이 화합물을 chlorination하여 O-ethyl phthalimidoalkylphosphonate을 만든후 diphenylmethyl 7-$\beta$-amino-3-acetoxymethyl-3-cephem-4-carboxylate와 coupling하여 지금까지 알려져 있지 않은 화합물 diphenylmethyl-7-$\beta$-(O-ethylphthalimidomethylphosphony1)-3-acetoxymethyl-3-cephem-4-carboxylate와 diphenylmethyl-7-$\beta$-[O-ethylphthalimidoethylphosphonyl]-3-acetoxymethyl-3-cephem-4-carboxylate를 각각 19%, 43%의 수율로 합성하였다.
