Studies in vitamin A. 10. Vitamin A1 and retinene1 in relation to photopic vision

Abstract

2) In the presence of ammonia the amino de- rivatives move much faster than the corresponding hydroxy compounds, but on changing to an acidic solvent this difference is greatly decreased and the relative positions may even be reversed. This is particularly evident in the case of the pyrimidines cytosine and uracil (and their ribosides) in which the reversal takes place at neutrality.