Authoheld the doubt that, according to the construction of synthetic lignin analog (A. Russel;J. Amer. Chem. Soc. 70, No. 3, 1060 (1948)), when it is oxydized, isohemipinic acid is produced but not veratric acid (lignin oxydations product), therefore supposed that the synthetic lignin analog would be different from the lignin in the wood.
In order to study its true form we observed the ultraviolet absorption spectrum of gymnosperm lignin and its analog by Hartley-Baly method.
In the dioxan-, ethanol gymnosperm lignin they had respectively one absorption band, the maximum absorption was 280mμ and the minimum absorption 261 mμ.
On the other hand the synthetic analog had two absorption bands, in the 1st absorption band, the wavelength of the maximum absorption was 280mμ, the minimum absorption 275mμ, in the 2nd absorption band, the wavelength of the maximum absorption was 265mμ, the minimum absorption 260mμ.
So we have supposed that the synthetic analog was different from the gymnosperm lignin in the wood.