Cycloaddition products (IMAGE) University of Münster Caption Single-crystal X-ray structures of two products arising from the cycloaddition reaction. In particular, on the left a unique five-four-three membered condensed ring system is visible. On the right, a four-six membered framework can be recognized. Carbon atoms are shown in grey, hydrogen atoms in white, nitrogen atoms in blue, oxygen atoms in red and chlorine atoms in green. Credit University of Münster - Peter Bellotti Usage Restrictions The use of the image is only permitted if the copyright is mentioned and in connection with this press release. License Original 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.