(3) The elemental composition of this substance was established by CH and N combustion analysis. (4) Separation of the mixlure into Its lndhridual components was accomplished by column chromatography at - 15 "C. (5) This substance was characterized by fuiiy consistent spectroscopic ('H NW, l3C NMR, IR, UV, mass spectrum) data. (6) All efforts to purify this substance by column chromatography at - 15 "C were frustrated by its tendency to undergo overall dehydration ...