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\begin{table}\caption{Anwendungs�bersicht �ber
 verschiedene Derivatisierungsreagenzien III
\label{tabdrehb}}
\centering
\setlength{\extrarowheight}{1pt}
\begin{tabular}{|ll|*5{c}|}\hline
& & \multicolumn{5}{c|}{\large\bfseries Substratklasse}\\
& & \rotatebox{90}{Alkohole}     &
   \rotatebox{90}{Amine}        &
   \rotatebox{90}{Aminos�uren}  &
   \rotatebox{90}{Carbons�uren} &
   \rotatebox{90}{Hydroxylgruppen} \\
\hline
\multirow{5}{3mm}{\rotatebox{90}{\large\bfseries Reagenz}}
& Bortrifluorid-Methanol-Komplex & & & x & & \\
& Chlortrimethylsilan & x & x & x & x & x \\
& Dichlordimethylsilan & & & x & & \\
& Hexamethyldisiloxan & & & & & x \\
& N-Methyl-bis(trifluoracetamid) & x & x & & & \\
\hline
\end{tabular}
\end{table}

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