1-carboxyethyl ethers

The first known 1-carboxyethyl ether of a sugar was 2-amino-3-0-[(/ )-l-carboxyethyl]-2-deoxy-D-glucose or muramic acid (37). It is a component of the polysaccharide moiety of the peptidoglycan in the bacterial cell-wall. It is partially replaced by the mamo isomer, 2-amino-3-6>-[(/ )-l-carboxy-ethyl]-2-deoxy-D-mannose, in the peptidoglycan from Micrococcus lyso-deikticus. 

Reaction of olefin oxides (epoxides) to produce poly(oxyalkylene) ether derivatives is the etherification of polyols of greatest commercial importance. Epoxides used include ethylene oxide, propylene oxide, and epichl orohydrin. The products of oxyalkylation have the same number of hydroxyl groups per mole as the starting polyol. Examples include the poly(oxypropylene) ethers of sorbitol (130) and lactitol (131), usually formed in the presence of an alkaline catalyst such as potassium hydroxide. Reaction of epichl orohydrin and isosorbide leads to the bisglycidyl ether (132). A polysubstituted carboxyethyl ether of mannitol has been obtained by the interaction of mannitol with acrylonitrile followed by hydrolysis of the intermediate cyanoethyl ether (133). 

Gerhardt et al. [34] described three possible ways to prepare alkylphenol-polyglycol ether carboxylates, namely, the method with NaOH and SMCA, the method by oxidation by means of oxygen, and the method whereby the nonionic reacts with acrylonitrile followed by hydrolyses with hydrochloric acid. The synthesis with acrylonitrile forms in contrast to the other two methods, carboxyethylated compounds with the general formula... 

Two known types of modification of monosaccharide units with formation of ether bonds include O-methylation and 0-(l-carboxyethyl)ation both (R)- and (S)-lactyl ethers have been identified. 

A homolog of carboxymethylcellulose, the carboxyethyl derivative, can be prepared by the condensation of such acrylic derivatives as acrylamide with alkali-cellulose.30 The homolog is water-soluble, and gives a clear, viscous solution. Proposed uses are similar to those mentioned for the carboxymethyl ether. 

To 5.69 g of this acetal in 410 ml of t-butanol and 11 ml of water was added a mixture of 5.80 g of potassium carbonate, 22,8 g of sodium periodate, and 270 mg of potassium permanganate in 1230 ml of water. The reaction mixture was stirred at 20-25°C for 20 hours and concentrated in vacuo to remove t-butanol. Ethylene glycole (0.5 ml) was added and reaction mixture extracted with 1 1 ether-benzene to remove neutral material. The aqueous layer acidified with solid sodium dihydrogen phosphate and extracted 4 times with 1 1 ethyl acetate-benzene. The organic layer was dried over sodium sulfate and evaporated to dryness in vacuo affording (+/-)-3-acetyl-2a-(2-carboxyethyl)-5-oxo-ip-cyclopentaneheptanoic acid methyl ester, 5-cyclic ethylene acetal as a mixture of the 3a and 3p isomers. 

A solution of 2.0 g of t-butyl alanine (S-form) and 3.78 g of ethyl 2-bromo-4-phenylbutanoate in 25 ml of DMF was treated with 1.8 ml of triethylamine and the solution was heated at 70°C for 18 hours. The solvent was removed at reduced pressure and the residue was mixed with water and extracted with ethyl ether. The organic layer was washed with water and dried over magnesium sulfate. Concentration of the solvent at reduced pressure gave the oily ethyl-a-[(l-carboxyethyl)amino]benzene-t-butanoate. 

A solution of 143.7 g of this t-butyl ester in 630 ml of trifluoroacetic acid was stirred at room temperature for one hour. The solvent was removed at reduced pressure and the residue was dissolved in ethyl ether and again evaporated. This operation was repeated. Then the ether solution was treated dropwise with a solution of hydrogen chloride gas in ethyl ether until precipitation ceased. The solid, collected by filtration, was a mixture of diastereoisomers of ethyl-a-[(l-carboxyethyl)amino]benzenebutanoate hydrochloride, melting point 153-165°C [a]D23 = +3.6° (1% MeOH). 

A stirred solution of 0.0158 mole of ethyl-a-[(l-carboxyethyl)amino] benzenebutanoate hydrochloride in 200 ml of methylene chloride was treated successively with 1.60 g (0.0158 mole) of triethylamine, 0.0158 mole of 1-hydroxybenzotriazole, 0.0158 mole of l,2,3,4-tetrahydro-6,7-dimethoxy-3-isoquinolinecarboxylic acid and then with 0.0158 mole of dicyclohexylcarbodiimide in 10 ml of methylene dichloride. Dicyclohexylurea gradually separated. The mixture was allowed to stand at room temperature overnight. Hexane (300 ml) was added and the urea was filtered. The filtrate was washed with 250 ml of saturated sodium bicarbonate, dried over sodium sulfate and concentrated to remove solvent. The viscous residue was triturated with 50 ml of ether and filtered to remove insolubles. The filtrate was concentrated to give 2-[2-[[l-(ethoxycarbonyl)-3-phenylpropyl]amino]-l-oxopropyl]-l,2,3,4-tetrahydro-6,7-dimethoxy-3-isoquinolinecarboxylic acid. 

Oxo-2,3-dihydro-4//-benzotelIurin3 27.6 g (9.3 mmol) of 2-carboxyethyl phenyl tellurium and 15.6 g (10 mmol) of butyl dichloromethyl ether are heated in the presence ofzinc(II) chloride at 50°. After evolution of hydrogen chloride has ceased, 100 m/ of carbon tetrachloride and activated charcoal are added. The resultant mixture is filtered, the solvent is evaporated from the filtrate on a water bath, and the residue is dissolved in 150 ml of dichloromethane. The solution is cooled to — 70° and 15 g (12 mmol) of aluminum trichloride are added in small portions to the cold solution. The mixture is allowed to warm to — 5 over 30 min, hydrolyzed with ice/water, and extracted with diethyl ether. The ether layer is separated, washed with aqueous sodium carbonate solution, dried, and the solvent is evaporated. The residue is distilled under vacuum and the fraction boiling at 150°/0.8 torr is collected. The product is recrystallized from methanol yield 1.45 g (60%) m.p. 34°. 

The reaction of glycidyl acrylate with a-(2-carboxyethyl)benzoin methyl ether has allowed one to obtain [101] the corresponding acrylic monomer which, upon copolymerization with different amounts of MMA, butyl methacrylate and 2-(V, V-dimethylamino)ethyl methacrylate, gives rise to polymeric photoinitiators, containing side-chain benzoin methylether moieties, for photocurable coatings ... 

It has been found [105,106] in particular that the reaction product [poly (BMEGMA-co-MMA)] derived from glycidyl methacrylate/methyl methacrylate copolymers [poly(GMA-co-MMA)] and a-(2-carboxyethyl)benzoin methyl ether (CEBME) (Scheme 26), although less efficient than CEBME alone in the UV initiated polymerization of styrene, exhibits a markedly enhanced photocrosslinking activity. 

Three kinds of reactive BAE derivatives such a-(2-carboxyethyl) benzoin alkyl ethers (BAE-CA), a-methylol benzoin alkyl ethers (BAE-OH) and newly synthesized a-(2-cyanato ethyl)benzoin alkyl ethers (BAE-NCO) are employed for preparing the polymeric photoinitiators. 

Methyl ethers of Man, mono-substituted at the 2, 3, 4 or 6 positions have been reported in the lipopolysaccharides of photosynthetic procaryotes [82, 83]. The reducing end of the mannans from Mycobacterium smegmatis and Streptomyces griseus have a terminal a-O-methyl group on C-l and Man30Me in the polymer chain. The lactic acid ether 4-0-[-(S)-l- carboxyethyl]-D-mannose is a component of extracellular polysaccharides of Mycobacterium spp., and a-amino-3-0-[-... 

Me randomly-methylated DM 2,6-di-O-methyl TM per-2,3,6-tri-0-methyl DMA peracetylated DM- -CyD 2-HE 2-hydroxyethyl 2-HP 2-hydroxypropyl 3-HP, 3-hydroxypropyl 2,3-DHP, 2,3-dihydroxypropyl Gi, glycosyl G2, maltosyl GUG, Glucuronyl-glucosyl DE 2,6-di-O-ethyl TE per-2,3,6-tri-0-ethyl CME O-carboxymethyl-0-ethyl TA per-2,3,6-tri-O-acyl (C2 Cig) TB per-2,3,6-tri-0-butanoyl TV per-2,3,6-tri-O-valeryl TO per-2,3,6-tri-0-octyl SBE4 d.s.4 of sulfobutyl ether group SBE7 d.s.7 of sulfobutyl ether group. Oi 25969 octasodium salt of octakis-S-(2-carboxyethyl)-octathio-y-CyD. 

Synonyms Siloxanes and silicones, dimethyl, 3-hydroxypropyl methyl, ethers with polyethylene glycol mono [3-[bis (2-carboxyethyl) amino] propyl) ether... 

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