Several genotoxic butenedioic acids present inchlorine-disinfected drinking water wereallowed to react with adenosine, guanosine, and cytidine in aqueoussolution. HPLC analyses,with detection at 254 and 310 nm, showed that clearly detectableproducts were formed onlyin the reactions with adenosine. The major products from thereactions between either 2-chloro-3-methyl-2-butenedioic acid (ox-MCF) or2-chloro-3-(chloromethyl)-2-butenedioic acid (ox-CMCF)and adenosine were the same. This substance was isolated by C18column chromatographyand characterized by UV absorbance,
1H and
13CNMR spectroscopy, and mass spectrometry.It was identified as3-(
-
D-ribofuranosyl)-7-carboxy-7-formyl-8-[9'-(
-
D-ribofuranosyl)-
N6-adenosinyl]-1,
N6-ethanoadenosine (cf
A,A).The yields of cf
A,A in reactions performed at pH7.4 and 37
C were 0.7% and 0.3% with ox-MCF and ox-CMCF,respectively.