| Popis: |
Two preparations of carbon-14 labelled 4-amino-3-(4-chlorophenyl)-butyric acid are described : First, the label is introduced in the 3-position of the butyric acid chain in nine steps, starting from 14CO2. The total radiochemical yield is 30%, calculated from the first labelled intermediate, i.e. 4-chlorobenzoic acid. Second, the 14C-atom is incorporated in the 4-position of the acid chain through three steps only, using K14CN as starting material with a yield of 39%. Synthesis of the title compound labelled with tritium in the benzene nucleus is performed by catalytic bromine-tritium exchange, affording a product with a specific radioactivity of 9.38 Ci/mmol. The des-chloro compound which is obtained as a by-product, is separated by column chromatography. |
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