2- bromoethyl ester

The choline ester is prepared by treating the 2-bromoethyl ester with trimethyl-amine. The ester is cleaved with butyrylcholine esterase (pH 6, 0.05 M phosphate buffer, rt, 50-95% yield). As with the morpholinoethyl ester, the choline ester imparts greater solubility to the C-terminal end of very hydrophobic peptides, thus improving the ability to cleave enzymatically the C-terminal ester. ... 

In a synthesis of the L-serine derivative 133, Kunz and Buchholz100 treated N-(benzyloxycarbonyl)-L-serine 2-bromoethyl ester (135) with tetra-O-benzoyl-a-D-glucopyranosyl bromide (136) protection of the... 

Method B (general procedure)7 To an NaHTe solution, prepared from tellurium powder (1.27 g, 10 mmol) and NaBH4 (0.9 g, 24 mmol) in absolute EtOH (25 mL), is added the 2-haloethyl ester (10 mmol) in EtOH (5 mL). (The reaction takes place instantaneously for 2-bromoethyl esters at room temperature.) The mixture is stirred for 1 h, then acidified with dilute HCl, extracted with ether and the organic phase dried and evaporated. The residue is recrystalUzed from appropriate solvents to give pure carboxylic acids. 

Bromoestrone, 38, 39 2-Bromoethanol, 77-78 2-(2-Bromoethyl)-l, 3-dioxane, 78 2-Bromoethyl esters, 77 a-Bromoketals, 427 Bromolactonization, 446 Bromomethyltrimethylsilane, 576... 

Cleavage of 2-bromoethyl esters. These esters can be cleaved by treatment with Still s reagent in THF and then with tetra-n-butylammonium fluoride (cf. cleavage of 2-trimethylsilylethyl esters, 8, 510). 

V-[(J )-2-Azido-2-[3,5-bis(benzyloxy)-4-methoxyphenyl]acetyl]-D-phenylglycine 2-Bromoethyl Ester... 

Bromoethyl esters The cleavage of ethylene acetals using bromoform as bromine source is achieved by refluxing in benzene, also in the presence of AIBN and TsOH. 

Treatment of adenosine 2, 3 -monophosphate with bromoethanol and hydrogen chloride in dioxan affords a mixture of the 2-bromoethyl esters of 2 - and 3 - AMP, with the latter isomer being favoured. 5 -(2-Bromoethyl)-AMP has been prepared by coupling bromoethanol to AMP using mesitylenesulphonyl chloride (MS-Cl). The bromoalkyl esters are reasonably stable in neutral media but react with nucleophilic side chains of amino acids, particularly cysteine, and should find application as affinity labels. 8-Sulphoadenosine-5 -phosphate has been prepared by heating 8-bromo-AMP with aqueous sodium sulphate. ... 

The inter- vs. intramolecular alkylation of 2-bromoethyl ester a anions (99) cannot be explained on simple terms. 

---