Puromycin (thing)

Puromycin is one of the antibiotics interfering with protein synthesis in the cell by releasing nascent polypeptide chains before their synthesis is completed. This is because it mimicks Aminoacyl-tRNA, which is normally involved. This is in prokaryotes as well as eukaryotes.
A second advantage of its structure is the alpha-amino group, which forms a covalent bond with the carboxyl end, causing dissociation from the ribosome.

     H3C  CH3
       \ /
	N
	|
	C   N
      // \ / \\
      N   C   CH
      |   ||  /
     HC   C--N
      \\  /  |
	N    |
	     |
	  O  |
  HOCH2 /  \ |
      |/    \|
      |\ __ /|
      H |  |
      H-N  OH
	|
	C=O
	|
	C-CH2-benzene ring-OCH3
	|
	NH2

Aminoacyl-tRNA looks the same, but with another side chain at the bottom Carbon atom (aka not the benzene ring).