An ideal medicament to dilate the pupil in order to acquire knowledge of the optic nerve, the retina and the vessels has long been sought. Its characteristics would include comfort in application to the conjunctiva, rapid and complete dilatation of the pupil, absence of effect on accommodation, general toxic effects and tendency to increase the intra-ocular tension, and finally an action persisting not more than one or two hours. Using such a drug, the physician could readily examine the fundi without taking a long time and without inconveniencing the patient and could feel entirely satisfied as to any ultimate consequences.
After the isolation of epinephrine in 19011 and the realization of the activities of this substance, numerous attempts were made at its synthesis. Also interest grew in the possible value of compounds presenting similar basic structures, and in 1909 Barger and Dale2 reported on a group of amines