Exemplar compounds used in the study (IMAGE) Chinese Academy of Sciences Headquarters Caption Cyclotene propionate (Comp.CP) is structurally a composite of methyl propionate (P) and methylcyclopentenone (C). Credit ZHOU Wen Usage Restrictions News organizations may use or redistribute this image, with proper attribution, as part of news coverage of this paper only. 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.