Modified inositols have emerged both as important probes of the enzymes of the phoso phatidylinositoi pathway 12~61 and also as inhibitors of cell growth [7][8][9]. Furthermore, certain cyclitol epoxides and related compounds have shown significant activity as inhibitors of various hydrolases 110-121. While eonduritol epoxides are widely used examples of potent, irreversible glycosidase inhibitors [ 10], compounds such as the bromoeonduritols and conduritol aziridines are just a few of the more recently developed examples 111,121. Lately there has been renewed interest in the discovery of novel glycosidase inhibitors as potential antiviral agents [ 13].
As part of our ongoing studies in the preparation and evaluation of novel eyclitols, we have developed an expedient route to the optically pure intermediate, 1L-2,3:4,5-bis-O-(tetraisopropyldisiloxane-l,3-diyl)-chiro-inositol (1), by utilizing the bifunetional protecting agent 1,3-diehloro-1,1,3,3-tetraisopropyldisiloxane { [ C! (MezCH) :Si ] :O }. The utility of this intermediate was subsequently demonstrated by transforming it into several important derivatives including conduritol B epoxide (3), 1 L-1,2-dideoxy-1,2-epithio-myoinositol (5), and the naturally occurring deoxy cyclitol, ( -)-viburnitol (4).
The [ CI(Me2CH) 2Si] 20 reagent was primarily developed for the simultaneous protection of the 3'-5'-hydroxy functions of nucleosides [ 14], but it has since proven to be quite a versatile blocking group for a large variety of diols [15][16][17]. Ozaki and co-workers have ~' For a preliminary report see Ref. [ 11.