Pterin chemistry. 46. Identification of substituted tetrahydropterins through gas chromatography and mass spectrometry

When treated with cyanide ion, 1,2:5,6-di-O-isopropylidene-α-_D-ribo-hexofuranos-3-ulose yields one or the other of the two corresponding epimeric cyanhydrines, depending on the experimental conditions. One of these epimers, reacted with ammonium cyanide, yields the corresponding amino-nitrile, the other being unreactive. Several derivatives of these compounds are briefly described.