1. Core ring: a pyridine (six-membered aromatic ring with nitrogen at position 1).
  
2. Substitution pattern on the pyridine:  
   - Chlorine atoms at positions 2 and 4 (i.e., ortho and para to the ring nitrogen).  
   - At position 6 (ortho to the ring nitrogen), a carboxamide group (-C(=O)-N-) is attached. The carbonyl carbon is bonded to the pyridine, and the amide nitrogen is incorporated into a piperazine ring (six-membered, with two nitrogens in para positions). 

3. Additional substitution on the piperazine:
   - The second nitrogen of the piperazine ring is acylated, bearing a carbonyl group.
   - That carbonyl carbon is bonded to the 2-position of an unsubstituted thiophene ring (five-membered aromatic with sulfur at position 1).

4. No stereocenters or double-bond stereochemistry are present.