Further investigation of the mass fragmentation of dinucleotide analogues containing the 6‐azauracil moiety

Abstract
The mass fragmentation of four dinucleotide analogues in which uracil and 6‐azauracil derivatives are connected by a trimethylene bridge is discussed. The fragmentation pathways have been proposed on the basis of high resolution data and metastable transitions. The distinct influence of alkyl substituents in the 5‐position of the uracil moiety on the fragmentation pathway has been observed and a novel fragmentation of 6‐azapyrimidine ring noted.