H2NC2H5\mathrm{H}_{2} \mathrm{NC}_{2} \mathrm{H}_{5}H2NC2H5
C6H5NO2\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NO}_{2}C6H5NO2
C6H5NH2\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NH}_{2}C6H5NH2
(H3C)3 N\left(\mathrm{H}_{3} \mathrm{C}\right)_{3} \mathrm{~N}(H3C)3 N