Table 1. Global Deprotection of GXM Glycan.
entry | substrate | catalyst | supplier | pretreatment | level of saturation of side products [%] | time [days] | yield [%] |
---|---|---|---|---|---|---|---|
1 | 1 | 20%Pd[OH]2/C | Sigma-Aldrich | noa | 39 | 5.5 | 66b* |
2 | 1 | 10% Pd/C | Sigma-Aldrich | noa | 53 | 4 | 57b* |
3 | 1 | 5% Pd/C | Strem Chemicals | noa | 10 | 1.5 | 84b* |
4 | 1 | 20%Pd[OH]2/C | Sigma-Aldrich | yesc | 0 | 6 | 66 |
5 | 1 | 10% Pd/C | Sigma-Aldrich | yesc | 0 | 5 | 58 |
6 | 1 | 5% Pd/C | Strem Chemicals | yesc | 0 | 2 | 88 |
7 | 1 | 20%Pd[OH]2/C | Sigma-Aldrich | nod | 36 | 6 | 67b* |
8 | 1 | 10% Pd/C | Sigma-Aldrich | nod | 54 | 4 | 57b* |
9 | 1 | 5% Pd/C | Strem Chemicals | nod | 9 | 2 | 82b* |
Untreated catalyst, EtOAc/MeOH/AcOH (4:1:1:1 v/v/v), 10 bar, and rt.
Combined yield of desired decasaccharide and saturated side products.
Preconditioned catalyst (see protocol), THF/tBuOH/PBS (phosphate-buffered saline) (100 mM pH 4) (60:10:30 v/v/v), 10 bar, and rt.
Untreated catalyst, THF/tBuOH/PBS (phosphate-buffered saline) (100 mM pH 4) (60:10:30 v/v/v), 10 bar, and rt. * this yield includes inseparable amounts of cyclohexyl methyl ether side products.