SPIN-LABELED C-GLYCOSIDE ANALOGS - DERIVATIVES OF OPENTYLIDENE-1,4-N-HYDROXYIMINO-DL-ERYTHROFURANOSE

A series of 2,3-O-cyclopentylidene C-glycoside analogs in which the fu ranose ring has been replaced with a N-hydroxypyrrolidine have been pr epared. A structural study of these tricyclic compounds and the aminox yl radicals thereof has been carried out using variable temperature H- 1 NMR, X-ray diffraction, molecular dynamics and EPR spectroscopy. Bot h types of compounds, N-hydroxypyrrolidines and pyrrolidine N-oxyls, f undamentally prefer - in solutions - N-endo conformations over the alt ernate, N-exo forms found by X-ray diffraction studies and computed to be more stable by molecular dynamics.