Comparing Cyclophellitol N‐Alkyl and N‐Acyl Cyclophellitol Aziridines as Activity‐Based Glycosidase Probes

Abstract

The synthesis and evaluation as activity-based probes (ABPs) of three configurationally distinct, fluorescent N-alkyl cyclophellitol aziridine isosteres for profiling GH1 β-glucosidase (GBA), GH27 α-galactosidase (GLA) and GH29 α-fucosidase (FUCA) is described. In comparison with the corresponding acyl aziridine ABPs reported previously, the alkyl aziridine ABPs are synthesized easily and are more stable in mild acidic and basic media, and are thus easier to handle. The β-glucose-configured alkyl aziridine ABP proves equally effective in labeling GBA as its N-acyl counterpart, whereas the N-acyl aziridines targeting GLA and FUCA outperform their N-alkyl counterparts. Alkyl aziridines can therefore be an attractive alternative in retaining glycosidase ABP design, but in targeting a new retaining glycosidase both N-alkyl and N-acyl aziridines are best considered at the onset of a new study.

Synthesis and application of a highly branched, mechanism-based 2-deoxy-2-fluoro-oligosaccharide inhibitor ofendo-xyloglucanases

“…A wide array of generally reactive, photo-activatable, or mecha-nism-based inhibitors based on bespoke glycan specificity motifs has been deployed, including carbasugar-epoxides (e.g. conduritol-β-epoxide, cyclophellitol), cyclopropylcarbasugars, epoxyalkyl glycosides, N-bromoacetylglycosylamines, bromoketone C-glycosides, glucosylthio-hydroquinones, aziridines, cyclosulfates, glycosylmethyl triazenes, activated phenylmethyl glycosides, various photoaffinity labels, and glycosides fluorinated at the 2-or 5-position (see comprehensive reviews and references therein, [12][13][14] and recent primary literature [15][16][17][18][19] ).…”

Spiro‐epoxyglycosides as Activity‐Based Probes for Glycoside Hydrolase Family 99 Endomannosidase/Endomannanase

“…Recombinant α‐galactosidase (GLA) was purchased from Genzyme (Cambridge, MA, USA). The α‐galactosidase ABP TB340 was synthesized as described earlier 37. Yeast mannan from S. cerevisiae was purchased from Sigma.…”

“…The a-galactosidase ABP TB340 was synthesized as described earlier. [37] Yeast mannan from S. cerevisiae was purchased from Sigma. (7): Compound 6 [45] (1.00 g, 3.80 mmol) was co-evaporated with dry toluene and dissolved in dry DMF (38 mL).…”

“…[35,36] We have previously demonstrated that fluorescent a-galacto-cyclophellitol aziridines such as TB340 covalently label GLA in activity-based manner. [37] Here, GLA was pre-labeled with TB340 to enablefluorescent detection on gel. Without additives, GLA gives ad istinct major band at % 50 kDa ( Figure 3B,l ane 1).…”

Biosynthesis and Biological Activity of Carbasugars

“…Several unnatural cyclophellitol derivatives also show interesting biological properties [234][235][236][237]. For instance, (1R,6S)-cyclophellitol 120, the unnatural diastereomer of cyclophellitol 5, is a potent -glucosidase inhibitor and cyclophellitol aziridines 121 are potent and selective irreversible inhibitors of retaining glycosidases [238][239][240][241][242][243] (see Figure 18).…”