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Showing papers on "Ether published in 1972"


Journal ArticleDOI
TL;DR: The results make it clear that external calcium or calcium in the transverse tubules play no essential part in action potential propagation or excitation-contraction coupling.

393 citations


Book
01 Jan 1972

204 citations



Journal ArticleDOI
TL;DR: The two dicarbonates may be useful as agents for selective blocking and deblocking of amino or other groups and in good yield under mild conditions.
Abstract: Di-t-butyl dicarbonate and one of its dithiol analogs, practical methods of preparation for which are given, react with amino-acid esters to form the N-t-butoxycarbonyl (t-BOC) derivatives and the thiol analogs in good yield under mild conditions. The thiol analogs are stable to acidic conditions, which rapidly remove the t-BOC group itself. t-Butyl trimethylsilyl carbonate forms a (CH(3))(3)Si ether from a N-thiol-t-BOC serine methyl ester. The N-thiol-t-BOC group can be removed from the -NHCOSR (R = t-butyl) by heating with peroxide-acetic acid.Action of the dicarbonates described above has not been attended by racemization in the cases examined. The two dicarbonates may be useful as agents for selective blocking and deblocking of amino or other groups.

135 citations



Journal ArticleDOI
TL;DR: This novel unsaturated ether fatty acid derivative, which contains a butadienylvinyl ether function, has the structure: [Formula: see text] and is formed from linoleic acid by a sequence of enzymic reactions.
Abstract: 1. A major component of the lipids in aqueous (pH7.5) homogenates of tuber tissue from Solanum tuberosum was isolated and characterized as 9-(nona-1′,3′-dienoxy)non-8-enoic acid. 2. This novel unsaturated ether fatty acid derivative, which contains a butadienylvinyl ether function, has the structure: [Formula: see text] and is formed from linoleic acid by a sequence of enzymic reactions. 3. A precursor of the unsaturated ether derivative is 9-d-hydroperoxyoctadeca-10,12-dienoic acid, formed by the action of S. tuberosum lipoxygenase on linoleic acid. 4. An enzyme that converts the fatty acid hydroperoxide into the unsaturated ether derivative was isolated from S. tuberosum . The pH optimum of this enzyme is approx. 9, although the overall conversion of linoleic acid into the ether derivative is maximal at pH7.5. 5. An unusual feature of this pathway is the insertion of an oxygen atom into the alkyl chain of a fatty acid. 6. This novel mechanism may play a role in the breakdown of polyunsaturated fatty acids to volatile products in plants.

109 citations



Journal ArticleDOI
TL;DR: The structure of an ornithine-containing lipid from Thiobacillus thiooxidans has been elucidated and it is indicated that the δ-amino group and the carboxyl group of Ornithine were free and that the extracted lipid existed as a zwitterion.

90 citations


Journal ArticleDOI
TL;DR: Aryl methyl ether demethylation using N,N-dimethylformamide has been shown to be a powerful reagent for cleanly and rapidly demethylating arylmethyl ethers in high yield as mentioned in this paper.
Abstract: Recent methods for demethylating aryl methyl ethers have been briefly reviewed, especially methods involving the use of nucleophilic reagents. Sodium thioethoxide dissolved in N,N-dimethylformamide has been developed as a powerful new reagent for demethylating aryl methyl ethers cleanly and rapidly in high yield. The reaction conditions can be controlled so that aromatic bromo substituents or isolated olefinic bonds are unaffected. Of special interest has been the selective monodemethylation of the methyl ethers of di- and tri-hydric phenols, exemplified by the isolation in high yield of orcinol monomethyl ether, p-methoxyphenol, guaiacol, and phloroglucinol dimethyl ether from the respective fully O-methylated compounds. An exception was pyrogallol trimethyl ether which afforded pyrogallol 1-monomethyl ether in high yield.

86 citations


Patent
Andre Viout1, Regine Pasero1
24 Nov 1972
TL;DR: Copolymers of vinyl acetate, crotonic acid and an unsaturated ester or ether are employed in cosmetic compositions for the hair as discussed by the authors, which are used in hair care applications.
Abstract: Copolymers of vinyl acetate, crotonic acid and an unsaturated ester or ether are employed in cosmetic compositions for the hair

67 citations


Journal ArticleDOI
TL;DR: One new and six known flavonoid methyl ethers were isolated variously from seven Artemisia taxa as mentioned in this paper, including dihydroquercetin 7,3′-dimethyl ether, which was obtained from A. pygmaea.

Patent
K Wagner1, G Oertel1, H Golitz1, I Golitz1, B Quiring1 
02 Nov 1972
TL;DR: In this article, a silyl-substituted urea derivative of controlled reactivity, high storage stability and which improved the properties of the cross-linked end products obtained by the prior art is described.
Abstract: This invention discloses a silyl-substituted urea derivative of controlled reactivity, high storage stability and which improve the properties of the cross-linked end products obtained by the prior art. The silyl-substituted urea comprises the general formula: WHEREIN R represents a C1-C18 alkyl, C4-C14 cycloalkyl or a phenyl radical, R'' represents a C1-C10 alkyl, C4-C10 cycloalkyl or C6-C10 aryl radical which may be halogenated or cyano-substituted, R'''' represents a hydrogen atom or a methyl or phenyl radical; R'''''' represents a hydrogen atom or a C1-C18 alkyl, C4-C14 cycloalkyl or C6-C14 aryl radical which may be halogenated or cyano-substituted; Q'' represents an alkyl radical containing from 4 to 12 carbon atoms with a valency of (b + 1) or a C4-C14 cycloalkyl, C7-C15 arylalkyl, C6-C14 aryl or C8 alkylaryl radical, all of which radicals have a valency of (b + 1); Q represents a c-valent radical which has been obtained by the removal of C HX groups from a compound with a molecular weight of 200 to 150,000, preferably from 4000 to 80,000, which contains ester, amide, urethane, thioether, acetal, urea, hydrazodicarbonamide, hydrazide and/or carbonate groups and may also contain additional ether groups; A 0, 1 OR 2; B 1 TO 7, PREFERABLY 1 OR 2; C 1 TO 8, PREFERABLY 2 OR 3 AND X O, S, NH or N-Y- (Y C1-C8 alkyl radicals).

Patent
29 Dec 1972
TL;DR: In this article, the removal of the metallic catalyst from reaction solutions in the presence of an OXYGEN-CONTANing GAS and a METAL-AMINE complete-complementary complete-metal component is discussed.
Abstract: METALLIC CATALYST RESIDUES ARE REMOVED FROM REACTION SOLUTIONS CONTANING POLYPHENYLENE ETHERS PRODUCED BY AN OXIDATIVE COUPLING OF A PHENOL IN THE PRESENCE OF AN OXYGEN-CONTANING GAS AND A METAL-AMINE COMPLEX CATALYST REMOVAL OF THE METAL COMPONENT IS EFFECTED BY CONTACTING THE SOLUTION WITH A COMPOUND CAPABLE OF SELECTIVELY COMPLEXING WITH THE METAL TO FORM A WATER SOLUBLE COMPOUND, REMOVABLE BY SUBSEQUENT LIQUID-LIQUID EXTRACTION WITH AN AQUEOUS MEDIUM. THE PROCESS IS LESS EXPENSIVE THAN PRIOR ART PROCEDURES PROVIDES SOLUTIONS WHICH ARE MORE EFFICIENTLY DECOLORIZED, AND REDUCES THE METALLIC RESIDUE CONTENT OF THE POLYPHENYLENE ETHER TO LEVELS LOWER THAN OTHER COMMERCIALLY ACCEPTABLE METHODS.

Journal ArticleDOI
TL;DR: The title compound 4 is prepared from vinyl ethyl ether and tert-butyllithium in the presence of TMEDA as mentioned in this paper, which gives 2-ethoxy-1phenyl-1-ol, which gives phenyl acetyl carbinol on acid catalyzed hydrolysis.


Journal ArticleDOI
TL;DR: When 2-hydroxyoestradiol-17β was incubated in the presence of S-adenosylmethionine with a 380-fold purified catechol O-methyltransferase from human liver, 2-methoxyoestradio-17 β and 3-methyl ether were identified as the only metabolites; magnesium was found to be the most effective cation.
Abstract: When 2-hydroxyoestradiol-17β was incubated in the presence of S-adenosylmethionine with a 380-fold purified catechol O-methyltransferase from human liver, 2-methoxyoestradiol-17β and 2-hydroxyoestradiol-17β 3-methyl ether were identified as the only metabolites. No dimethylation, transmethylation or demethylation was observed. The purified enzyme was active only in the presence of cysteine and divalent cations; magnesium was found to be the most effective cation. The temperature optimum for the methylation of 2-hydroxyoestradiol-17β was 42°C; the activation energy amounted to 20.9 kcal/mol. The enzyme activity had two pH optima; the pH optimum between 6.8 and 8.4 was due to maximal formation of 2-methoxyoestradiol-17β, whereas the pH optimum at 9.2 was due to the formation of both the 2- and 3-monomethyl ether. The formation of the two isomeric monomethyl ethers increased to a maximum at a substrate concentration of 50 μM (Km value 14 μM) and then decreased with an inflection point between 75 and 100 μM (K1 value under standard assay conditions 95 μM). Whereas both monomethyl ethers were formed at the same rate up to 50 μM substrate concentration, the decrease of formation of 2-hydroxyoestradiol-17β 3-methyl ether was more pronounced than that of 2-methoxyoestradiol-17β. Both substrate inhibition and the ratio of methylation depended on the concentrations of S-adenosylmethionine and MgCl2. Product inhibition was also demonstrated with K1 values of 24 μM for 2-methoxyoestradiol-17β, 80 μM for 2-hydroxyoestradiol-17β 3-methyl ether and 39 μM for S-adenosylhomocysteine. In contrast, increasing amounts of S-adenosylmethionine did not produce inhibition or changes of the ratio of methylation (Km value 8.5 μM).

Patent
10 Apr 1972
TL;DR: New WATER-SOLUBLE HYDROXY-ETHYL METHYL CELLULOSE ETHERS have been pre-prepared as discussed by the authors, which are improved thinners for latex paint.
Abstract: NEW WATER-SOLUBLE HYDROXYETHYL METHYL CELLULOSE ETHERS HAVE BEEN PREPARED WHICH ARE IMPROVED THICKENERS FOR LATEX PAINT. THESE NEW ETHERS HAVE A THERMAL GEL POINT GREATER THAN 100*C., A HYDROXYETHYL MS OF ABOUT 1.0-3.5, A METHOXY DS OF ABOUT 0.6-1.6 AND A TOTAL DS OF ABOUT 1.4-2.4. LATEX PAINT THICKENED WITH THESE NEW ETHERS HAS IMPROVED ENZYME RESISTANCE AND COMPATIBILITY WITH PREDISPERSED COLORANTS.

Journal ArticleDOI
01 Oct 1972-Polymer
TL;DR: In this article, the initial rate constants for the self condensation of halogenophenoxides in anhydrous dimethyl sulphoxide were also determined, and the order of the halogen reactivities was F>CI~Br with p-halogenophenyl sulphonyl groups showing greater reactivity than the o-isomers, while displacement from the m −halogeno sulphones was very slow and comparable with the rate of sulphone bond fission.


Patent
10 Jul 1972
TL;DR: In this article, liquid detergent compositions are provided comprising a surfactant and a peroxide bleaching agent, having good storage stability by virtue of their being substantially free from liquid water, and dissolved or dispersed in a polyhydric alcohol or ether thereof which is liquid at ambient temperature.
Abstract: Liquid detergent compositions are provided comprising a surfactant and a peroxide bleaching agent, having good storage stability by virtue of their being substantially free from liquid water, and dissolved or dispersed in a polyhydric alcohol or ether thereof which is liquid at ambient temperature.

Journal ArticleDOI
TL;DR: In this paper, the radical scavenging technique used in conjunction with e.s.r. spectroscopy has been employed to characterise radicals produced by photolysis of benzoin, benzil, and methyl ether.
Abstract: The radical scavenging technique used in conjunction with e.s.r. spectroscopy has been employed to characterise radicals produced by photolysis of benzoin, benzoin methyl ether, and benzil with reference to their relative efficiencies as photoactivators for radical polymerization. Radicals trapped by N-oxides and nitroso-compounds indicate that while benzoin and its methyl ether are photochemically cleaved in a similar manner, the latter produces radicals more efficiently. Possible mechanisms are presented.

Journal ArticleDOI
TL;DR: The use of the but-2-enyl (crotyl) ether system for the protection of hydroxy-groups was investigated and it was found that these ethers were stable to mild acid hydrolysis and to the basic conditions required for benzylation.
Abstract: 2,4,6-Tri-O-benzyl-D-galactopyranose was prepared from allyl 3-O-allyl-2,4,6-tri-O-benzyl-α-D-galactopyranoside for use in the synthesis of oligosaccharides containing a galactose residue substituted on the 3-position. The use of the but-2-enyl (crotyl) ether system for the protection of hydroxy-groups was investigated. The but-2-enyl ethers were stable to mild acid hydrolysis and to the basic conditions required for benzylation, and were readily cleaved by the action of potassium t-butoxide in dimethyl sulphoxide. Prop-1-enyl 2,4,6-tri-O-benzyl-α-D-galactopyranoside was prepared from allyl 2,4,6-tri-O-benzyl-3-O-but-2-enyl-α-D-galactopyranoside and prop-1-enyl 2-benzamido-4,6-di-O-benzyl-2-deoxy-β-D-glucopyranoside was prepared from allyl 2-benzamido-4,6-di-O-benzyl-3-O-but-2-enyl-2-deoxy-β-D-glucopyranoside. 2-Benzamido-3,4,6-tri-O-benzyl-2-deoxy-D-gluco- and D-galacto-pyranoses were prepared from the corresponding β-allyl glycosides.

Journal ArticleDOI
TL;DR: In this article, the authors show that the oxygen not present in quinone, lactone, or phenolic form is present as aromatic ring-type ether groups, and suggest that the presence of quinones and lactones is associated with significant chemical reactivity.
Abstract: Results of this infrared study give strong qualitative support for the presence of quinones and support the presence of lactones. Considerable chemical reactivity is associated with the presence of these two groups. Absorption typical of phenols and ethers was obtained in the 1205–1195 cm−1 and 1275-1265 cm−1 regions; and it is suggested by this study that the oxygen not present in quinone, lactone, or phenolic form is present as aromatic ring-type ether groups.

Journal ArticleDOI
TL;DR: In this paper, the reaction with bromine in ether at −70° yields an intermediate bromoadamantyloxonium tribromide which decomposes to 1-bromo-3-ethoxyadamantane on warming.
Abstract: Tetracyclo[3.3.1.13.7.01..3]decane (i.e., 1,3-dehydroadamantane or DHA) and its 5,7-dimethyl derivative may be synthesized from the corresponding 1,3-dibromoadamantane compounds with sodium–potassium alloy in ether or heptane. These highly strained cyclopropyl compounds are very reactive towards free radical and electrophilic reagents. They homopolymerize 140–160° to thermally resistant, insoluble materials and spontaneously copolymerize with oxygen in solvents at room temperature. Reaction with bromine in ether at −70° yields an intermediate bromoadamantyloxonium tribromide which decomposes to 1-bromo-3-ethoxyadamantane on warming. Other rapid reactions of these strained 1,3-dehydroadamantanes are reported.


Journal ArticleDOI
TL;DR: Asperentin, a minor metabolic product of an entomogenous strain of Aspergillus flavus grown in surface culture on synthetic media, has been shown to be 3,4-dihydro-6,8- dihydroxy-3-(6-methyltetrahydropyran-2-ylmethyl)isocoumarin (I; R1= R2= H).
Abstract: Asperentin, a minor metabolic product of an entomogenous strain of Aspergillus flavus grown in surface culture on synthetic media, has been shown to be 3,4-dihydro-6,8-dihydroxy-3-(6-methyltetrahydropyran-2-ylmethyl)isocoumarin (I; R1= R2= H). The major secondary metabolic product formed under these conditions was the 8-O-methyl ether (I; R1= H, R2= Me); additional minor products were the 6-O-methyl ether and three closely-related phenolic compounds, one of which was shown to be a 5′-hydroxyasperentin (III; R1= R2= H, R3= OH).

Journal ArticleDOI
TL;DR: Nigrescin, the first optically active 2-hydroxy-2-benzylcoumaranone, and a (+)-2,3- trans -flavan-3,4- cis -diol, represent new members of the natural 3′,4′,7,8-tetrahydroxyflavonoid group as mentioned in this paper.

Journal ArticleDOI
TL;DR: In this paper, the dilithio compounds of 1- and 2-alkynes were attacked by electrophiles first at the 3 position, and a 1.3-sigmatropic shift occurred in the monolithioallenes to give terminal acetylides.

Patent
H Fabris1, R Herold1, E Maxey1
24 Nov 1972
TL;DR: In this article, the authors describe a process for the preparation of a polyurethane, which consists of: (1) CHEMICALLY reacting (A) AN ORGANIC POLYISOCYANATE and (B) A COPOLYMER SELECTED from the Class Consisting of A COPOYMER OF A LOWER ALKYL ACRYLATE OR METHACRYLate with A POLYALKYLENE ETHER ITAConate HAVING AN EQUIVALENT WIEHGT of about 100 TO 3000 PER
Abstract: 1. A PROCESS FOR THE PREPARATION OF A POLYURETHANE WHICH COMPRISES (1) CHEMICALLY REACTING (A) AN ORGANIC POLYISOCYANATE AND (B) A COPOLYMER SELECTED FROM THE CLASS CONSISTING OF A COPOLYMER OF A LOWER ALKYL ACRYLATE OR METHACRYLATE WITH A POLYALKYLENE ETHER ITACONATE HAVING AN EQUIVALENT WIEHGT OF ABOUT 100 TO 3000 PER HYDROXYL GROUPS ANOF CON AINING ONE TO THREE HYDROXYL GROUPS PER MOLECULE; A COPOLYMER OF STYRENE WITH A POLYALKYLENE ETHER ITACONATE HAVING AN EQUIVALENT WEIGHT OF ABOUT 100 TO 300 PER HYDROXYL GROUP CONTAINING ONE TO THREE HYDROXYL GROUPS PER MOLECULA; AND A COPOLYMER OF A VINYL COMPOUND SELECTED FROM VINYL CHLORIDE, VINYLIDENE CHLORIDE AND VINYL ACETATE WITH A POLYALKYLENE ETHER MALEATE HAVING AN EQUIVALENT WEIGHT OF ABOUT 100 TO 3000 PER HYDROXYL GROUP AND CONTAINING ONE TO THREE HYDROXYL GROUPS PER MOLECULE; AND (2) RECOVERING A POLYURETHANE OF IMPROVED PHYSICAL AND CHEMICAL PROPERTIES INCLUDING INCREASE TENSIILE STRENGTH INCREASED MODULUS OF ELASTICITY AND INCEASED SOLVENT RESISTANCE.

Journal ArticleDOI
TL;DR: In this article, it was suggested that aryloxycopper (I) is an intermediate in the Ullmann condensation, etc., and it was shown that I can be synthesized by the interaction of phenylcopper with phenols and then characterized.
Abstract: Some aryloxycoppers were synthesized by the interaction of phenylcopper with phenols and then characterized. The reaction of aryloxycopper and organic halide in diglyme generally gave the corresponding ether. From these and other results, it is suggested that aryloxycopper (I) is an intermediate in the Ullmann condensation, etc.