A student performed analysis of aliphatic organic compound ' $X$ ' which on analysis gave $\mathrm{C}=61.01 \%$, $\mathrm{H}=15.25 \%, \mathrm{~N}=23.74 \%$. This compound, on treatment with $\mathrm{HNO}_2 / \mathrm{H}_2 \mathrm{O}$ produced another compound ' Y ' which did not contain any nitrogen atom. However, the compound ' $Y$ ' upon controlled oxidation produced another compound ' $Z$ ' that responded to iodoform test. The structure of ' $X$ ' is :