Alternative aspirins as antisickling agents: acetyl-3,5-dibromosalicylic acid.

Acetyl-3,5-dibromosalicylic acid (dibromoaspirin) is shown to be a potent acylating agent of intracellular hemoglobin in vitro. Transfer of the actyl group of dibromoaspirin to amino groups of hemoglobins A and S seems to occur predominantly at just two or three sites on these proteins. This acetylation produces moderate increases in the oxygen affinities of normal and sickle erythrocytes. Furthermore, treatment of intracellular hemoglobin S with dibromoaspirin directly inhibits erythrocyte sickling. This antisickling effect is paralleled by an increase in the minimum gelling concentration of deoxy hemoglobin S extracted from sickle erythrocytes that had been exposed to low concentrations of dibromoaspirin. These observations suggest that dibromoaspirin might be an effective antisickling agent in vivo.