Trace derivatization of cytosine with pentafluorobenzoyl chloride and dimethyl sulfate

Methods are being developed for derivatizing trace amounts of DNA adducts for ultimate determination by gas chromatographic techniques. High-pressure liquid chromatography is used to optimize appropriate derivatization reactions for the determination of cytosine. A single vial reaction scheme involves acylation with electrophoric pentafluorobenzoylchloride followed by alkylation with dimethyl sulfate. Currently, the overall yield for this reaction starting with 50 nmole of cytosine is 59 +/- 4.6%.