In this task, you are given a sentence. You are expected to recognize the name of any form of chemical substances. Although there might be several correct answers, you need to write one of them.

Example Input: Anti-inflammatory trends of 1, 3-diphenyl-2-propen-1-one derivatives.
Example Output: 1, 3-diphenyl-2-propen-1-one

Example Input: Identification of a primary target of thalidomide teratogenicity.
Example Output: thalidomide

Example Input: Analysis of NMDA receptors in the human spinal cord.
Example Output:
NMDA