Preparation of di-O-triphenylmethyl-(trityl-)cyclomalto-octaoses, and isolation and characterization by "hex-5-enose degradation" of four positional isomers.

Four regioisomeric ditritylated derivatives of cyclomalto-octaose (1, cG8), namely, 6(I),6(n)-di-O-trityl-cG8S have been prepared by the reaction of 1 with chlorotriphenylmethane in pyridine and isolated by high-performance liquid chromatography. The regiochemical determination of the four ditrityl-substituted derivatives has been achieved by means of the "hex-5-enose degradation," followed by examination of the products by fast-atom bombardment-mass spectrometry.