3-Diazirine-derivatives of bile salts for photoaffinity labeling.
New carbene-generating photolabile bile salt derivatives, 3,3-azo-7 alpha,12 alpha-dihydroxy-5 beta [7 beta-3H]cholan-24-oic acid and (3,3-azo-7 alpha,12 alpha-dihydroxy-5 beta [7 beta-3H]cholan-24-oyl)-2- aminoethanesulfonic acid were synthesized with high specific radioactivity. These 3-diazirine-derivatives could be activated to the corresponding carbenes by irradiation with ultraviolet light at 350 nm with a half-life time of 2 min. The 3-diazirine derivatives behaved in enterohepatic circulation like the natural bile salts. The uptake of [3H]taurocholate into isolated hepatocytes was competitively inhibited by (3,3-azo-7 alpha,12 alpha-dihydroxy-5 beta-cholan-24-oyl)-2- aminoethanesulfonic acid indicating that the 3,3-azo-derivative of taurocholate shares the hepatic transport systems for natural bile salts. It was demonstrated that the radioactively labeled 3-diazirine bile salt derivatives are useful probes for photoaffinity labeling of bile salt binding proteins especially in intact cells and tissues.
Institut für Organische Chemie und Biochemie, Universität Freiburg, Federal Republic of Germany.
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W
Kramer
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S
Schneider
D000345:Affinity Labels / Q000138:chemical synthesis*; D000818:Animals; D001647:Bile Acids and Salts / Q000378:metabolism*; D001692:Biological Transport; D003978:Diazomethane; D003979:Diazonium Compounds / Q000138:chemical synthesis* / Q000378:metabolism; D004764:Enterohepatic Circulation; D008099:Liver / Q000378:metabolism; D010777:Photochemistry; D051381:Rats
D000345:Affinity Labels; D001647:Bile Acids and Salts; D003979:Diazonium Compounds; D003978:Diazomethane