Systems combining phosphorothioate and bridging oxygen-substitutions (Table 3, entry 7) have demonstrated potential as therapeutics against Alzheimer’s disease owing to their metal Selleck TGF beta inhibitor ion chelation properties [47 and 48]. The use of sulfur-based analogues in the determination of mechanism has been reviewed recently [49]. Recent synthetic advances have also given (easier) access

to: azido-phosphonate dNTPs, where bridging O-atoms have been replaced by CHN3 groups (Table 3, entry 8), and these analogues can be isolated as separate diastereomers [50]; and oxymethyl analogues (CH2 insertion between O and P within anhydride linkages) for following ApnA and NpnN degradation and metabolism (Table 3, entry 9) [51]. Phosphonate NDP-sugar analogues, where the C1-oxygen of the glycosyl group has been replaced by methylene, have given insight into the mechanism of UDP-apiose/UDP-xylose synthase (Table 3,entry 10) [52], and bis-α,β-β,γ-CF2-NTPs offer sterically undemanding mimics that do not hydrolyse while maintaining comparable polarity properties to their natural NTP progenitors (Table 3,entry 11) [53]. Multi-faceted approaches

combining several experimental techniques and/or computational methods are currently giving some of the clearest pictures of phosphoryl transfer strategies. Most of these approaches have, in principle, been available for some time, however, experimental difficulties have precluded their exploitation. Synthesis www.selleckchem.com/products/Gemcitabine-Hydrochloride(Gemzar).html of analogues remains a substantial obstacle, with many ‘obvious’ analogues only becoming

accessible through painstaking development of challenging routes. This is particularly true of the phosphoanhydride systems. Fortunately, several groups are working towards more convenient methodologies for the preparation of phosphoesters, anhydrides and their analogues, and details of these efforts can be accessed elsewhere [55, 56•, 57, 58, 59, 60•, 61, 62, 63•, 64, 65•, 66, 67, 68•• and 69]. Heavy isotope kinetic studies have proven extremely enlightening, however, the measurement of these extremely small effects (even in best case scenarios) remains the preserve of a few specialist groups. Combinations learn more of experimental approaches with computational methods are also allowing more rigorous, quantitative assessment of observed kinetic data, where interpretations of kinetic results can often be complex. In summary, synthetic methodology, in tandem with kinetic measurements and computational dissection are providing enzymologists with an enhanced toolbox for the determination of phosphoryl transfer mechanisms. Papers of particular interest, published within the period of review, have been highlighted as: • of special interest HJK was funded by a postdoctoral grant from the Jenny and Antti Wihuri Foundation. LPC was funded by a PhD studentship from EPSRC.