%% 
%%  The LaTeX Graphics Companion, 2ed (first printing May 2007)
%% 
%%  Example 8-2-36 on page 539.
%% 
%%  Copyright (C) 2007 Michel Goossens, Frank Mittelbach, Denis Roegel, Sebastian Rahtz, Herbert Vo\ss 
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 

\documentclass{ttctexa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{207.83385pt}

\StartShownPreambleCommands
\usepackage{xymtexps}
\StopShownPreambleCommands
\begin{document}
\changeunitlength{0.09pt}
\furanose{1Sa==H;2Sb==H;2Sa==OH;3Sb==H;%
3Sa==OH;4Sa==H;4Sb==HOC\rlap{H$\sb{2}$};%
1Sb==\fiveheterov[bd]{1==N;2==N;4==N}
{1==(yl);3==CONH$\sp{2}$}}
\end{document}