SYNTHESIS OF 2-IMINO-3-[1-（#beta#-D-RIBOFURANOSYL)OXO]-1H,5H-1,5-BENZODIAZEPINE THROUGH CONDENSATION OF O-PHENYLENEDIAMINE WITH FORMYLISOXAZOLE GLYCOLIDE

摘要

The synthesis of 3-[1-(#beta#-D-ribofuranosyl)oxo]-1H1,5-benzodiazepine (3) and 2-imino-3-[1-(#beta#-D-ribofuranosyl)oxo]-1H,5H-1,5-benzodiazepine (8) is described.The cyclocondensation of enaminone glycoside (1)with o-phenylenediamine afforded benzodiazepine (2)in 64% yield.The reaction of formylisoxazole (4) with o-phenylenediamine led to three products,iminobenzodiazepine (5),benzimidazole (6),and enaminone nitrile (7) in 33%,27%,and 9% yields,respectively.Removal of the sugar protecting groups in 2 and 5 with aqueous sodium carbonate in methanol gave the dejprotected C-nucleosides (3 and 8).