Complex sentence: Among the most important was the discovery of the anticonvulsant properties of phenytoin (Dilantin); the technique he used, along with Tracy Putnam, to identify this compound ushered in the modern era of drug therapy for epilepsy.
Split into simpler sentences: Among the most important was the discovery of the anticonvulsant properties of phenytoin (Dilantin). The technique he used, along with Tracy Putnam, to identify this compound ushered in the modern era of drug therapy for epilepsy.