Date of Award


Publication Type

Doctoral Thesis

Degree Name



Chemistry and Biochemistry


Chemistry, Biochemistry.




Three 4-azidobenzenesulfonates were studied as potential reversible and irreversible inhibitors (photoaffinity labeling reagents) of the human erythrocyte anion exchange system by monitoring their effect on the rate of {('35)S}-sulfate self-exchange at equilibrium. In the dark 4-azido, 2-nitro-4-azido, and 3,5-diiodo-4-azidobenzenesulfonates were reversible inhibitors of sulfate self-exchange with 50% inhibition concentrations (ID(,50) values) of 8.6 (+OR-) 0.46, 0.86 (+OR-) 0.007 and 0.40 (+OR-) 0.004 mM, respectively. If the compounds were first photolyzed at 350 nm and then checked as reversible inhibitors the first two were less potent (ID(,50)'s doubled) while the diiodo compound became a much more potent inhibitor. Photolysis at 350 nm in the presence of cells was carried out at concentrations around the respective ID(,50) values at 0(DEGREES)C and 37(DEGREES)C. At 0(DEGREES)C maximum irreversible inhibition of 4, 53 and 33% were observed with the 4-azido, 2-nitro-4-azido and 3,5-diiodo-4-azido compounds at 2.5, 0.5 and 0.092 mM respectively. At 37(DEGREES)C maximum inhibition of 3, 73 and 25% were observed at respective concentrations of 2.5, 0.5 and 0.092 mM. Further chemical characterization of the diiodo compound photolysis mixtures indicated that azido group decomposition was incomplete and the possibility that the compound was deiodinating upon photolysis was discussed. Additional kinetic characterization of the diiodo compound as a reversible inhibitor showed that it could possibly be non-competitive with respect to sulfate, but no definite conclusion has been arrived at.Dept. of Chemistry and Biochemistry. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1983 .T348. Source: Dissertation Abstracts International, Volume: 44-03, Section: B, page: 0783. Thesis (Ph.D.)--University of Windsor (Canada), 1983.