N-Hydroxysuccin imide

Cuatrecasas, P., and Parikh, I. (1972) Adsorbents for affinity chromatography. Use of N-hydroxysuccin-imide esters of agarose. Biochemistry 11, 2291-2299. 

JW Anderson, JE Zimmerman, FM Callahan. The use of esters of N-hydroxysuccin-imide in peptide synthesis. J Am Chem Soc 86, 1839, 1964. 

Mercaptoundecanoic acid (450561-5G), N-hydroxysuccin-imide (NHS) (130672-25G), N-(3-dimethylaminopropyl)-M-ethylcarbodiimide hydrochloride (EDC) (E1769-1G), and ethanolamine (236381-50G) can be purchased from Sigma-Aldrich. EDC quickly oxidizes under air atmosphere. A good way of handling EDC is to separate it into aliquots immediately after opening the container for the first time, then store aliquots at -20°C. 

This procedure was also applied to the synthesis of the closely related 6-O-nocardomycoloyl-MDP (49) (66) and 6 0-corynomycoloyl-MDP (50) 47, 66). In these instances the internal ester (f) was not formed when N,N -dicyclo-hexylcarbodiimide in presence of N-hydroxysuccin-imide was used as coupling reagent (57). Similar 6-O-acyl-derivatives of MDP (51—55) have been synthesized in the same manner, the synthetic fatty acyl group being linear, a-branched and a-branched-P-hydroxyl-ated (57). 

Scheme 19 Preparation of biomimetic cyclophane-type gelators (a) N-hydroxysuccin-imide, DCC, THF, 0°C (b) H2N(CH2)nNH2, DME, room temp. HBr in AcOH (33%), basic workup (c) l,3-bis(bromomethyl)benzene, tetrabutylammonium bromide, CH3CN, reflux...

DNA can also be conjugated with amino-modified TEOS nanoparticles following their activation with 1,2,3-triazine and 1,2,4-triazine, and subsequent reaction with amino-labeled synthetic oligonucleotides [69]. Alternatively, the amino-modified TEOS nanoparticles can be activated with m-maleimidobenzoyl-N-hydroxysuccin-imide ester cross-hrikers and then reacted with thiol-labeled synthetic oligonucleotides [70]. 

Keyhole limpet hemocyanin (Sigma, USA) using maleimido-benzoyl-N-hydroxysuccin-imide ester essentially as described by Harlow and Lane (1988). Antipeptide antiserum were raised in rabbits using a schedule of boosting at three weeks intervals followed by bleeding ten days after each boost. Antipeptide antibodies were affinity purified with immobilised synthetic peptide on epoxy-activated Sepharose 6B (Pharmacia). 

In solution-phase peptide synthesis, acylation of amino acids or peptides with N-protected azetidine-2-carboxylic acid is performed via the active esters, e.g. A-hydroxysuccin-imide 100 111-112 or pentachlorophenyl ester, m 117 as well as by the mixed anhydride 101114 or carbodiimide 118 methods. An attempt to prepare the A-carbonic acid anhydride by cycli-zation of A-(chloroformyl)azetidine-2-carboxylic acid with silver oxide in acetone or by addition of triethylamine in situ failed, presumably due to steric hindrance. 111 In SPPS, activation of the Fmoc-protected imino acid by HBTU 119,120 is reported. In solution-phase peptide synthesis, coupling of N-protected amino acids or peptides to C-protected azetidine-2-carboxylic acid or related peptides may be performed by active esters, 100 118 121 mixed anhydrides, 95 or similar methods. It may be worth mentioning that the probability of pip-erazine-2,5-dione formation from azetidine-2-carboxylic acid dipeptides is significantly reduced compared to proline dipeptides. 111 ... 

The Bsmoc derivative is formed from the chloroformate or the At-hydroxysuccin-imide ester. It is cleaved rapidly by aMichael addition with tris(2-aminoethyl)amine at a rate that leaves Fmoc derivatives intact. More hindered bases such as N-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. In the following example, Fmoc protection was unsuccessful because of purification problems associated with removal of the by-products from Fmoc deprotection. ... 

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