\documentclass{ppex}
\nonstopmode
\AtBeginDocument {\setlength \unitlength {0.09pt}}
\usepackage {epic,carom}
\pagestyle{empty}
\setlength\textwidth{207.0pt}
\begin{document}
\ResetPreambleCommands
\ReadyForTheFray
\usepackage {epic,carom}
\naphdrv[ob]
  {1Sb==Br;1Sa==Br;3D==O}
\naphdrh[A]
  {1==Cl;4==F;2==CH$_{3}$}
\end{document}