3-Fluoro sialosyl fluorides

As previously shown, 3-fluoro sialosyl fluorides could be employed as donor substrates for TcTS. Due to the fluoro substituent and its pronounced electron-withdrawing features at the anomeric center, these derivatives show delayed reactions with acceptor structures [28]. This effect proved to be useful in determination of essential mechanistic aspects, since the intermediate enzyme substrate complex could be crystallized and studied [25, 26]. By further modification via introduction of a 9-benzamide function as in compound 24 this effect was increased. In contrast to the expected outcome the enhanced binding of this aromatic residue was unexpectedly due to its location in the acceptor-binding site rather than in the glycerol sidechain binding domain, as evidenced by X-ray structural studies (Fig. 11) [52]. 

Fig. 11 3-Fluoro sialosyl fluoride derivative with acceptor site binding properties in TcTS [52]...

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See also in sourсe #XX -- [ ]

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