Rink amide polystyrene resin

An efficient combinatorial solid-phase synthesis of asymmetric cyanine dyes was developed by Isacsson and Westman [17] using a Rink amide polystyrene resin. The picolinium and lepidinium salts 6 were linked to the solid-phase resin by amide coupling, then the benzothiazole derivatives 7 were subsequently condensed with the coupled picoline and lepidine moieties to give the yellow to blue (Amax ahs = 420-590 nm) asymmetric, fluorescent (Amax em = 480-650 nm) cyanine dyes 8 (Scheme 5.2, Fig. 5.3). As a consequence of restricted rotation upon intercalation, the fluorescence quantum yields increase significantly when these dyes are bound to DNA. 

Very recently, a polymer-supported construct for quantifying the reactivity of monomers involving multicomponent Ugi strategies was reported [53]. The authors investigated the Ugi four-component condensation of a set of aldehydes, acids, and isonitriles. The amine compound used was bound to a specially modified Rink amide polystyrene resin bearing an ionization leveler and bromine functionality as a mass splitter for accurate analysis by positive electrospray ionization mass spectrometry. The microwave-assisted experiment was performed with a set of ten carboxylic acids, hydrocinnamaldehyde, and cyclohexyl isonitrile in DCM-... 

Brown EG, Nuss JM. Alkylation of Rink s amide linker on polystyrene resin a reductive amination approach to modified amine-linkers for the solid phase synthesis of /Y-substiuited amide derivatives. Tetrahedron Lett 1997 38 8457-8460. 

Peptoid dendrimers were synthesised using an Fmoc solid-phase strategy using a Rink amide linker and an aminomethyl-polystyrene resin and microwave-mediated DIC/HOBt chemistry (Fig. 25). The use of microwave heating allowed each... 

Dimethoxyphenyl-Fmoc-aminomethyl)-phenoxymethyl-polystyrene resin (A-Fmoc Rink amide resin [24]) can be purchased from a variety of sources. Work reported herein used resin purchased from Bachem Bioscience Inc. (King of Prussia, PA) (see Note 3). 

For this, the polystyrene resin bearing 3-bromobenzamide attached to the solid phase via a Rink amide linker was used. The 3-bromophenyl resin (75) (500 mg, 0.39 mmol), Pd(PPh3)2Cl2 (13.7 mg, 0.020 mmol), Cul (7.4 mg, 0.039 mmol), triphenylphosphine (20.5 mg, 0.078 mmol), the alkyne (28) (0.43 mmol), diethylamine (1.5 mL, 13.60 mmol), and DMF (0.5 mL) were stirred in a modified heavy-walled Smith Process Vial [200] at 120 °C for 25 min in the microwave cavity. The resin was then washed as follows ... 

Hydroxyethylene resin HMPA resin Chloromethyl resin Hydroxymethyl resin Tritylchloride resin Rink amide resin Wang resin REM resin Aminomethyl resin Chloromethyl resin Wang resin Rink amide resin PAL amide resin MBHA resin Chloromethyl resin Chlorotrityl resin Wang resin PAM resin Polystyrene resin Chloromethyl resin Chlorotrityl resin Wang resin Rink amide resin Sasrin resin Polystyrene resin Chloromethyl resin Benzoic acid resin Wang resin Trityl resin 2-Chlorotrityl resin PAL resin Rink amide resin MBHA resin REM resin Hydroxymethyl resin Polystyrene Aminomethyl resin Chloromethyl resin 2-Chlorotrityl resin Hydroxyethyl resin Rink amide resin Wang resin MBHA resin Sieber resin... 

Rink amide resin, (2,4-dimethoxy)henz-hydrylamine resin, a polystyrene handle combination suitable for cleavage of peptide amides with 95% TFA [H. Rink, Tetrahedron Lett. 1987, 28, 3787]. 

Trautwein and co-workers described an efficient method for the solid-phase s thesis of TV-substituted pyrroles, including tetrasubstituted pyrroles. Highly substituted pyrroles are functional components of compounds such as atorvastatin (Lipitor), an HMG-CoA reductase inhibitor used for lowering cholesterol. Reaction of p-ketoamides 29, prepared from polymer bound acetoacetamide using a series of primary amines in trimethylorthoformate (not shown), with a-bromoketone derivatives 30 in the presence of 2,6-di-tertbutylpyridine (DTBP) and DMF yielded pyrroles 31 with diverse functionality in high purity. The authors found that polystyrene Rink amide resin was the best solid support because it was able to withstand the acetoacetylation conditions required to produce the polymer bound acetoacetamide. 

Glycopeptide 31 was synthesized in a custom-made, fully automatic continuous-flow peptide synthesizer constructed essentially as described elsewhere (19). A resin consisting of a cross-linked polystyrene backbone grafted with poly(ethylene glycol) chains (TentaGel , Rapp Polymer, Germany) and functionalized with the Rink amide linker (p-[a-(fluoren-9-ylmethoxyformamido)-2,4-dimethoxybenzyl]phenoxyacetic acid, Nova-biochem, Switzerland) was used for the syntheses. DMF was distilled before use. 

In 2006, Griebenow and coworkers [31] described the palladium-catalyzed a-arylation of ketones on a solid support using modified Buchwald-Hairtwig reaction conditions. The coupling of immobilized 4-bromobenzamide (prepared from polystyrene Rink amide resin and 4-bromobenzoic acid chloride) with several aromatic, heteroaromatic, and aliphatic ketones was investigated. 

Brol997a Brown, E.G. and Nuss, J.M., Alkylation of Rink s Amide Linker on Polystyrene Resin A Reductive Amination Approach to Modified Amine-Linkers for the Solid Phase Synthesis of N-Substituted Amide Derivatives, Tetrahedron Lett., 38 (1997) 8457-8460. 

Because of the origins of solid phase chemistry in peptide synthesis, amide formation is historically one of the most important reactions on solid supports. The most pubUc resins are the Rink amide linker 123 [146,147] and its derivatives that are formed by addition of the Knorr hnker [148] to polystyrene-derived resins. 

Most of the polyamine syntheses on solid support have been carried out on resins that are modified from Merrifield (100), Wang (101), and Rink-Amide resins (102) (Fig. 19) depending on the synthesis strategies, the coupling procedures, and the branching, fii this review, we illustrate the polystyrene (PS) scaffold of the resins as depicted in Fig. 19. Table 1 presents an overview of the most common resins used in polyamine synthesis (103-120), which will be described in the remaining sections. 

On the other hand, if the phosphopeptides are intended to be used in solution-phase assays, the synthesis can be carried out on a standard resin with common linkers. This includes the Rink amide or Wang-type linkers on polystyrene, TentaGel, or ChemMatrix supports. Upon completion of the peptide chain assembly, the peptides are released from the solid support by treatment with TFA-containing cocktails with concomitant removal of acid-labile side-chain protecting groups. Using these conditions robust protocols for rapid and efficient synthesis of phosphopeptides have been established. 

In a similar approach, a pretuned glass encased microchip set to emit a unique binary code is placed in a polypropylene tea bag loaded with polystyrene beads. Using a modified split synthesis approach, a 125-membered tripeptide library N-capped as the /r-carboxy-cinnamic acid amide was prepared on Rink resin. Each porous reactor contained a radio frequency transporter which successfully defined the structure of two inhibitors of protein tyrosine phosphatase [37],... 

---