Which of the following compounds is not aromatic?

Cyclic conjugation

Lone pair involved in aromaticity

Having $=6\text{π}{e}^{-}$ Aromatic




Cyclic conjugation and by Huckel rule $=6\text{π}{e}^{-}$

So aromatic




Cyclic conjugation $6\text{π}{e}^{-}$

Cyclic conjugation lp of $-N$ is involved in delocalization

Having $=6\text{π}{e}^{-}$ Aromatic




Cyclic conjugation and by Huckel rule $=4\text{π}{e}^{-}$

So ,Anti-aromatic