%% 
%%  The LaTeX Graphics Companion, 2ed (first printing May 2007)
%% 
%%  Example 8-2-20 on page 531.
%% 
%%  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{348.0pt}
\StartShownPreambleCommands
\usepackage{array}\usepackage{xymtexps}
\StopShownPreambleCommands
\begin{document}
\setlength{\tabcolsep}{1mm}
\changeunitlength{.05pt}
\begin{tabular}{@{}>{\small}lcccc@{}}\hline
\emph{N}
 & \multicolumn{4}{c@{}}{\itshape\small Specific commands}\\\hline
1
 & \pyridinev       {1==a1;2==a2;3==a3}
  & \pyridinevi     {1==a1;2==a2;3==a3}
   & \pyridineh     {1==a1;2==a2;3==a3}
    & \pyridinehi   {1==a1;2==a2;3==a3} \\[-1mm]
 & \footnotesize\verb|\pyridinev|
  & \footnotesize\verb|\pyridinevi|
   & \footnotesize\verb|\pyridineh|
    & \footnotesize\verb|\pyridinehi| \\
2,4
 & \pyrazinev       {1==a1;2==a2;3==a3}
  && \pyrazineh     {1==a1;2==a2;3==a3}
   & \\[-3mm]
 & \footnotesize\verb|\pyrazinev|
  && \footnotesize\verb|\pyrazineh|
   & \\
1,3
 & \pyrimidinev     {1==a1;2==a2;3==a3}
  & \pyrimidinevi   {1==a1;2==a2;3==a3}
   & \pyrimidineh   {1==a1;2==a2;3==a3}
    & \pyrimidinehi {1==a1;2==a2;3==a3}  \\[-1mm]
 & \footnotesize\verb|\pyrimidinev|
  & \footnotesize\verb|\pyrimidinevi|
   & \footnotesize\verb|\pyrimidineh|
    & \footnotesize\verb|\pyrimidinehi|  \\
1,2
 & \pyridazinev     {1==a1;2==a2;3==a3}
  & \pyridazinevi   {1==a1;2==a2;3==a3}
   & \pyridazineh   {1==a1;2==a2;3==a3}
    & \pyridazinehi {1==a1;2==a2;3==a3}  \\[-1mm]
 & \footnotesize\verb|\pyridazinev|
  & \footnotesize\verb|\pyridazinevi|
   & \footnotesize\verb|\pyridazineh|
    & \footnotesize\verb|\pyridazinehi|  \\
1,3,5
 & \triazinev       {1==a1;2==a2;3==a3}
  & \triazinevi     {1==a1;2==a2;3==a3}
   & \triazineh     {1==a1;2==a2;3==a3}
    & \triazinehi   {1==a1;2==a2;3==a3}  \\[-1mm]
 & \footnotesize\verb|\triazinev|
  & \footnotesize\verb|\triazinevi|
   & \footnotesize\verb|\triazineh|
    & \footnotesize\verb|\triazinehi|    \\\hline
\end{tabular}
\end{document}