Succinimide esters

The succinimide derivative (234) can be used in peptide synthesis for conversion of amino acids into their succinimide esters (235 Scheme 41) (79CL1265). 3-Substituted mercapto-1,2-benzisothiazole 1,1-dioxides (236) have been recommended as an odourless means of storage of thiols. The latter are readily regenerated by the action of piperidine (81CL1457). 

The Bsmoc derivative is formed from the chloroformate or the A -hydroxy-succinimide ester. It is cleaved rapidly by a Michael addition with tris(2-aminoethyl)amine at a rate that leaves Fmoc derivatives intact. More hindered bases, such as A -methylcyclohexylamine or diisopropylamine, do not react with the Bsmoc group, but do cleave the Fmoc group, illustrating the importance of steric effects in additions to Michael acceptors. 

Phenacyl-6-aminopenicillate HCI D-Phenylglycyl Chloride HCI 4-Hydro xy-1,5-naphthyridine-3-carboxylic acid-N-succinimide ester... 

I n the above procedure, the use of 4-hydroxy-1,5-naphthyridine-3-carbonyl chloride in place of 4-hydroxy-1,5-naphthyridine-3-carboxyllc acid N-succinimide ester can also afford the same objective compound as above. The use of sodium thio-n-propoxide in place of sodium thiophenoxide can also give the objective compound in the form of the sodium salt. 

The most widely applied principle is haptenylation of amino groups via A-hydroxy succinimide esters (NHS-ES). For convenient protein-labeling procedures,... 

Alternatively, the water-insoluble biotinylated succinimide ester can be first dissolved in fresh distilled dimethylsulfoxide (10 mg/mL), and then added to the IgG solution. 

Many biotinylated succinimide esters are now available. Most of these variations alter the size of the spacer arm between the succinimide coupling group and the biotin. The additional spacers could facilitate avidin binding and, thus, may be critical for some applications (9). 

If a free amino group forms a portion of the protein that is essential for activity (e.g., the antigen-combining site for antibody), biotinylation with the succinimide ester will lower or destroy the activity of the protein, and other methods of labeling should be tried. Biotin hydrazide has been used to modify the carbohydrate moieties of antibodies (10,11). Other alternatives are the thiol-reactive biotin maleimide (12) or biotin iodoacetamide (13). 

Fig. 8 Examples of homobifimctional crosslinkers a bisimidate and b N-hydroxy-succinimide ester...

Boc-aminooxyacetic succinimide ester in DMF (10 equiv, 0.5 M) was added to commercial amino Spherilose affinity resin (1 equiv) preswollen in DMF for 3 h. The resin was washed with DMF and the Boc group removed by treatment with neat TFA (2 min). The resin was washed again with DMF and neutralized with 10% DIPEA/DMF, and washed again with DMF. After thorough washing with CH2a2, the derivatized solid support 15 was dried. 

Preparation of the Au-Coated Glass Slide with Reactive Succinimide Esters... 

Activate the introduced carboxy groups on the Au surface to form reactive succinimide esters using a solution of 0.1 mol/L EDC and 0.4 mol/L NHS in water for 15 min. 

To make a reference for the 3-D NPH-streptavidin (3-D NPH-SA), the solution including no poly (NAM-co-NAS) was dispensed on the Au-coated slide activated with succinimide esters. The product was referred to as 2-D reference (2-D SA). 

Immerse the slide in 1 M ethanolamine solution, 3% BSA (pH 8.5) for blocking nonspotted surface of Au-coated slide and masking the nonreacted succinimide esters at 25°C for 30 min. 

Because the succinimide esters of poly(NAM-co-NAS) are susceptible to be hydrolyzed during storage, store purified polymer in a desiccator before usage. It is able to be used within 1 year losslessly. 

The spotting experiment must be finished within 1 h after preparing streptavidin/poly (NAM-co-NAS) mixed solutions. Because the reaction between the succinimide esters of poly(NAM-co-NAS) and the amino groups of SA molecules and hydrolysis of the succinimide esters of poly (NAM-co-NAS) proceed before printing on substrates in 384-well, 3-D NPH-SA is difficult to be made on Au-coated slide activated with succinimide esters. 

Slepnev et al. [313] presented a simple method for protein radio-labeling with Bolten-Hunter reagent (iV-hydroxy succinimide ester of 3-(p-hydroxy di-iodophenyl)) propionic acid) in AOT/octane-RMs using mouse IgG, human transferrin, protein A, and a2-interferon as labeling examples. The yield of radio-labeling in RMs was found to be higher than that achieved in homogeneous aqueous solution. 

Tor and co-workers have developed a strategy for appending ruthenium(II) and osmium(II) polypyridyl complexes to nucleotides, by using succinimide esters as shown in Fig. 31 (197). These have been shown to incorporate into DNA without altering the global conformation, and still exhibit metal-centered luminescence (198). 

Boc amino acid thioesters 7 used in Boc-SPPS are prepared by reaction of Boc amino acid active esters such as the 4-nitrophenyl ester (ONp) or succinimide ester 6 (OSu) with thiols containing a carboxy group that can link to a resin (Scheme 3, Table 2). 1314 Amino acid thioesters 7 can also be prepared by reaction of Boc amino thiol acids 8 with a chloro, bromo, or hydroxy compound that also contains a carboxy group (Scheme 3, Table 2). 1516 ... 

N-(y-Maleimidobutyryloxy)succinimide ester (GMBS) is a heterobifunctional cross-linking agent that contains an NHS ester on one end and a maleimide group on the other (Fujiwara etal., 1988) (Pierce). Its internal cross-bridge contains a linear 4-car-... 

Di- and oligo-peptides with a terminalo-aminophosphonous acid residue have been prepared by coupling with N-hydroxy succinimide esters of N-benzyloxycarbonylamino acids or peptides. 

---