反应详情

The hapten [10-O-(carboxypropyl)]ractopamine ether(Hapten A—derivatised at position 10) was prepared in three steps according to FIG. 3 of the accompanying drawings, from 4-(4-hydroxyphenyl)-2-butanone, 2. The reaction of 4-(4-hydroxyphenyl)-2-butanone, 2 with ethyl 4-bromobutyrate in dimethylformamide (DMF) in the presence of sodium hydride (NaH), gives ethyl 4-[4-(3-oxobutyl)phenoxy]butanoate 3. The ketoester, 3, obtained was reacted with octopamine hydrochloride, 4, in methanol in the presence of triethylamine (TEA) and sodium cyanoborohydride (Na BH3CN) to give 10-O-[3-(ethoxycarbonyl)propyl]ractopamine ether 5, in moderate yields. The hapten A was obtained after saponification of the ester, 5, with sodium hydroxide (NaOH) (2N) in methanol.