Resins polyethylene glycol

Any standard resin used for solid-phase peptide synthesis can be used with microwave irradiation including, but not limited to, polystyrene (PS) resin, polyethylene glycol-PS (PEG-PS) resin, PEG, and cross-linked ethoxylate acrylate (CLEAR) resin. 

Polyoxyethylene Esters. This series of surfactants consists of polyoxyethylene (polyethylene glycol) esters of fatty acids and aUphatic carboxyhc acids related to abietic acid (see Resins, natural). They differ markedly from mono- and diglycerides in properties and uses. 

For some nonionic, nonpolar polymers, such as polyethylene glycols, normal chromatograms can be obtained by using distilled water. Some more polar nonionic polymers exhibit abnormal peak shapes or minor peaks near the void volume when eluted with distilled water due to ionic interactions between the sample and the charged groups on the resin surface. To eliminate ionic interactions, a neutral salt, such as sodium nitrate or sodium sulfate, is added to the aqueous eluent. Generally, a salt concentration of 0.1-0.5 M is sufficient to overcome undesired ionic interactions. 

Toyopearl resin Particle size ( tm) Pore size (A) Polyethylene glycols and oxides Dextrans Globular proteins... 

The same approach was readily adaptable to solid-phase synthesis. A small library of unnatural derivatives of 140 was prepared with variation of the configuration and nature of R1 and R4 and with substitution on the benzene ring <2000JC0186>. Three natural alkaloids, Verrucine A, B, and Anacine, were synthesized by a similar pathway and the pyrazino[2,l- ]quinazoline as opposed to the benzodiazepine structure of Anacine was proved <2001JNP1497>. Fiscalin B and other derivatives were prepared by solid-phase synthesis using polyethylene glycol (PEG) resin <2002USP6376667>. 

Initial solid phase synthesis25 was carried out on Merrifield s resin (1 % crosslinked chloromethylated styrene/divinylbenzene copolymer, 200-400 mesh) because of its track record in solid-phase peptide synthesis.26 Unfortunately, the Merrifield resin has limitations as a carbohydrate carrier to study interactions between the carbohydrates and relevant binding proteins. The hydrophobic nature of the resin leads to nonspecific, irreversible protein adsorption.27 Later work utilized Rapp s TentaGel, an amphiphilic, polyethylene glycol resin.28... 

S Zalpsky, JL Chang, F Albericio, G Barany. Preparation and applications of polyethylene glycol-polystyrene graft resin supports for solid-phase peptide synthesis. Reactive Polymers 22, 243, 1994. 

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