\documentclass{standalone}
\usepackage{chemfig}
\begin{document}
\setatomsep{3em}
\rlap{\tikz[baseline]\node[draw,circle,inner sep=2pt] at (0,3em) {1};}
\chemfig{
\textcolor{blue}{H_2N}
-[,,,,blue]\chemabove{C}{\alpha\hspace{1em}}
(-[2,,,,green]\textcolor{green}{R})
(-[6]H)
-[,,,,red]\textcolor{red}{C}
(-[7,,,,red]\textcolor{red}{OH})
(=[1,,,,red]\textcolor{red}{O})
}
\quad\vrule\quad
\rlap{\tikz[baseline]\node[draw,circle,inner sep=2pt] at (0,3em) {2};}
\chemfig{
\color{blue}\chemabove{H_3N}{\hspace{2em}\oplus}