\documentclass[12pt,border=1pt]{standalone}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{chemfig,chemmacros}
\usepackage{lmodern}

\chemsetup[chemformula]{font-shape=sf,format=\sffamily}
\renewcommand*\printatom[1]{\ensuremath{\mathsf{#1} } }
\setatomsep{2.5em}
\setdoublesep{.6ex}
\setarrowdefault{,.75}
\setbondstyle{thick}

\begin{document}
\chemfig{
	*6((-O-[::-60])
    	= (-O-[::-60])
        - (-O-[::60])
        =
        - ( -(=[::60]O)-[::-60]NH-[::60,,1]-[::-60]-[::60]-[::-60]-[::60]-[::-60](=[::-60]O)-[::60]OH
        )
        =
        -
     )
}
\end{document}