Method for detecting methylated cytosine by using bisulfite reaction

A method for converting non-methylated cytosine in a single-stranded DNA to uracil, comprising subjecting the single-stranded DNA to bisulfite reaction in the presence of at least one of compounds shown by the following general formula [1] to [8];

• a compound shown by the following general formula [1]
• wherein R1 to R6 represent each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms;
• n represents an integer of 1 to 3;
• a compound shown by the following general formula [2]
• wherein Y represents a carbon atom, an oxygen atom or a nitrogen atom;
• R7 to R12 represent each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms;
• k represents an integer of 0 to 2, but when Y is an oxygen atom, k represents 0, when Y is a nitrogen atom, k represents 1, and when Y is a carbon atom, k represents 2;
• a compound shown by the following general formula [3]
• wherein R13 to R15 represent each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms;
• a compound shown by the following general formula [4]
• wherein R17 and R19 represent each independently a hydrogen atom, an amino group or an alkyl group having 1 to 6 carbon atoms;
• R16, R18 and R20 represent each independently a hydrogen atom, an amino group, an alkyl group having 1 to 6 carbon atoms or a dialkylamino group having 2 to 6 carbon atoms;
• and R16 and R17 may form a benzene ring together with a carbon atom adjacent to R16 and a carbon atom adjacent to R17;
• a compound shown by the following general formula [5]
• wherein R21 and R22 represent each independently an alkyl group having 1 to 6 carbon atoms;
• and X2 represents a counter anion;
• a compound shown by the following general formula [6]
• wherein R23 represents an alkyl group having 1 to 6 carbon atoms;
• R24 to R28 represent each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms;
• and X2 represents a counter anion;
• a compound shown by the following general formula [7]
• wherein R29 to R34 represent each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms;
• a compound shown by the following general formula [8]
• wherein Z represents a nitrogen atom or a carbon atom;
• m represents an integer of 0 or 1, and when Z is a nitrogen atom, m represents 0, and when Z is a carbon atom, m represents 1;
• R35 to R39 represent each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.