Structural specificities in acylation of hemoglobin and sickle hemoglobin by diaspirins.

Double-headed aspirins with bridging groups of different length and molecular structure have been examined for their reactivity with hemoglobin A or S. The compounds constructed are bound in the beta-cleft and show a wide range of beta-beta cross-linking effectiveness. Oxygenation curves of the modified hemoglobins in the presence of inositol hexaphosphate are strikingly modified. Many of the diaspirins also produce substantial changes in the minimum gelling concentration of sickle hemoglobin. These reagents offer possibilities for further enhancement of specificity toward hemoglobin, particularly by taking advantage of stereoselectivities.