Pyridine Coupling (IMAGE) Colorado State University Caption The left image is a modification of the antihistamine drug loratadine made via the pyridine-pyridine coupling method developed by CSU chemists. The bold line represents the reaction, the result of which is a derivative of loratadine obtained with 70 percent yield. The right image is a 3D representation of the coupling reaction. Credit Juan Alegre-Requena/Colorado State University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.