Abstract: Novel compounds are disclosed which have the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 may be the same or different and independently selected from the group consisting of hydrogen, halogen, straight and branched chain alkyl of from 1-6 carbon atoms, aryl, cycloalkyl of 4 to 7 carbon atoms; and alkoxy of 1 to 6 carbon atoms; R.sub.5 and R.sub.6 may be the same or different and are selected from the group consisting of hydrogen, halogen, straight and branched chain alkyl groups of from 1-6 carbon atoms, aralkyl groups wherein the alkyl portion has from 1-6 carbon atoms cycloalkyl of from 4-7 carbon atoms and aryl; R.sub.7 is hydrogen or a straight or branched chain alkyl group of 1-6 carbon atoms and the pharmaceutically acceptable salts thereof.These compounds are useful for the treatment of hyperlipidemia and for the in vivo and in vitro treatment of hemoglobin or blood to modify the affinity of hemoglobin for oxygen.