Syntheses of new nonionic radiographic contrast media: acylamino-triiodophenyl ethers of sugars.

New, potentially useful radiographic contrast media, employing hexoses attached to the triiodophenyl moiety by an ether bond, have been synthesized and tested. Two of the nitro groups in trinitrobenzene were displaced by two fully protected glycose-3-yl residues. The bis-ethers (IV) were successively reduced, iodinated, acylated, and then subjected to base and/or acid catalyzed deprotection to obtain the acylamino-triiodophenyl ethers (VIII). The bis-glucose-3-yl ether (VIIIa) was converted into the corresponding bis-arabinos-2-yl ether (XIII) by standard methods. These sugar ethers have high water solubility, hydrolytic stability, and low toxicity. The glycolyl-bis-hexose ether DL-2-98, which has the lowest neurotoxicity in this series of compounds, is comparable to iopamidol, and is potentially useful as a new nonionic radiographic contrast agent.