$C{H_3}CN\xrightarrow{{Na + {C_2}{H_5}OH}}X\xrightarrow{{HN{O_2}}}Y\mathop {\xrightarrow{{{K_2}C{r_2}{O_7}}}}\limits_{{H_2}S{O_4}} Z$
image $\mathop {\xrightarrow{{NaN{O_2}}}}\limits_{HCl} A\,\,\xrightarrow{{CuCN}}B\,\,\mathop {\xrightarrow{{{H_2}}}}\limits_{Ni} C\,\,\xrightarrow{{HN{O_2}}}D$