UV Spectral Characteristics and Acidic Dissociation Constants of 280 Alkyl Bases, Nucleosides, and Nucleotidesa

The λ_max (nm), in those cases where more than one value has been reported, are either the most frequent value or an average of several values, the range being ± 1 to 2 nm for the λ_max. Since the λ_min is more sensitive than the λ_max to impurities in the sample, the values of λ_min in the table are generally the lowest reported. Values in parentheses are shoulders or inflexions. The cationic and anionic forms are either so stated by the authors or are arbitrarily taken at pH 1 and pH 13. Individual values are given for pK_a except when there are more than two values. In that case, a range is given.