Thiohydroximate 7-sulfonates

The oxime, 34, is glycosylated by a UDPG-thiohydroximate glucosyltransferase, and subsequently sulfonated by sulfotransferase to yield a glucosinolate of the type Thus, aldoximes generated by initial oxygenation of amino acids are found to serve as substrates of a wide variety of plant enzymes that act directly at the hydroximino function. 

The intact glucosides are probably not the active agents, but rather the isothiocyanates, thiocyanates, and nitrile derivatives derived from them. The initial hydrolysis products are thiohydroximate 0-sulfonates, which are followed by rearrangements to give isothiocyanates, and, under some conditions, nitriles and thiocyanates are also formed (Dewick, 1984). In contrast to the intact glucosinolates, most of the hydrolysis products are relatively volatile (Fig. 17.6). 

---