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Tarek Kassem David Sabatino Xin Jia X. X. Zhu William D. Lubell 《International journal of peptide research and therapeutics》2009,15(3):211-218
A comparative study is presented on the solid-phase peptide synthesis (SPPS) of the acyl carrier protein (ACP 65–74) sequence
on a series of Rink amide resins possessing different matrix structures: poly(vinyl alcohol)-graft-poly(ethylene glycol) (PVA-g-PEG, 4), Tentagel-S-RAM (TG, 5), NovaGel (NG, 6), ChemMatrix (CM, 7) and polystyrene-divinylbenzene (PS-DVB, 8). In this comparison, the PEG-containing resins proved significantly better suited for the synthesis of pure ACP target sequence
than the conventional PS-DVB solid supports (75–90% versus 52% crude purity). Amongst themselves, the PEG resins 4-7 exhibited similar capacity for providing pure peptide. Selecting PVA-g-PEG resin for a comparison of Rink amide linker versus no linker, the ACP (65–74) sequence was synthesized directly on the
PVA-g-PEG resin 1, under identical conditions as employed in the synthesis on resin 4 bearing the Fmoc Rink linker, except for the final cleavage step, which was performed under more environmentally sound conditions
using ester displacement with aqueous ammonia. Relative to its Rink amide counterpart 4, PVA-g-PEG resin 1 was cheaper to produce and possessed twice as much loading capacity (0.48 vs. 0.81 mmol/g). Moreover, Rink-less resin 1 gave higher yields of isolated pure peptide (61 vs. 45%) relative to its Fmoc Rink linker counterpart 4. In light of these results, the importance of the linker has been brought into question. As the need for large scale solid-phase
peptide synthesis grows with greater demand for peptide products, ideal resins should be inexpensive to produce and employable
under environmentally sound conditions to provide pure products. In this light, PVA-g-PEG resin 1 has demonstrated significant promise for economic and “green” SPPS. 相似文献
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The synthesis of the first polymer-supported TADDOL is reported. Its efficiency as chiral ligand of Ti(IV) was studied in the Diels-Alder cycloaddition of cyclopentadiene to 3-crotonoyl-1,3-oxazolidin-2-one, and was superior to that observed for its homogeneous equivalent. (4R,5R)-α,α,α′,α′-2-pentaphenyl-4,5-dimethanol-1,3-dioxolane. Recycling of the heterogeneous Ti(IV)-TADDOLate was also studied, being the most suitable method for the repreparation of the catalyst from the ligand after use. Chirality 9:191–197, 1997. © 1997 Wiley-Liss, Inc. 相似文献
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