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Showing papers on "Alkylation published in 1968"




Patent
30 Sep 1968
TL;DR: In this paper, the use of these agents as DRAINAGE AIDS, RETENTION AGENTS, and FLOTATION AGENTS in CONNECTION with RELATIVELY THICK PAPER or CARDBOARD MANUFACTURE is also discussed.
Abstract: NOVEL CATIONICALLY ACTIVE, WATER SOLUBLE POLYAMIDES OBTAINED BY THE ALKYLATION WITH A BIFUNCTIONAL ALKYLATION AGENT UNTIL THE ALKYLATION AGENT IS USED UP, OF A REACTION PRODUCT RESULTING FROM THE REACTION OF A DICARBOXYLIC ACID OR A FUNCTIONAL DERIVATIVE THEREOF WITH A POLYALKYLENEPOLYAMINE ARE PRODUCED, EXEMPLIFIED ALKYLATION AGENTS HAVING THE FORMULA CL-CH2-CH(-OH)-CH2-N(+)(-CH3)2-CH2-CH(-OH)-CH2-N(+)(-CH3)2 -CH2-CH(-OH)-CH2-CL 2CL(-) CL-CH2-CH(-OH)-CH2-N(+)(-CH3)2-CH2-CH2-N(+)(-CH3)2-CH2- CH(-OH)-CH2-CL 2CL(-) EXEMPLIFIED REACTION PRODUCTS OF A DICARBOXYLIC ACID WITH A POLYALKYLENEPOLYAMINE BEING THE REACTION PRODUCTS OF DIETHYLENETRIAMINE WITH ADIPIC ACID, OF DIETHYLENETRIAMINE AND TRIETHYLENETETRAMINE WITH ADIPIC ACID, OF BIS-(3AMINOPROPYL)-AMINE WITH ADIPIC ACID AND N,N''-BIS-(3AMINOPROPYL)-1,4-DIAMINO-BUTANE WITH ADIPIC ACID DIMETHYL ESTER; THE USE OF THESE EXEMPLIFIED CATIONICALLY ACTIVE, WATER SOLUBLE POLYAMIDES AS DRAINAGE AIDS, RETENTION AGENTS AND FLOTATION AGENTS IN CONNECTION WITH RELATIVELY THICK PAPER OR CARDBOARD MANUFACTURE IS ALSO EXEMPLIFIED.

162 citations


Journal ArticleDOI
TL;DR: The results confirmed the concepts that alkylation of cellular DNA induces lesions which interfere with DNA replication, but which can be enzymically ;repaired'.
Abstract: 1. A quantitative study was made of the relationship between survival of colony-forming ability in Escherichia coli strains B/r and B(s-1) and the extents of alkylation of cellular DNA, RNA and protein after treatment with mono- or di-functional sulphur mustards, methyl methanesulphonate or iodoacetamide. 2. The mustards and methyl methanesulphonate react with nucleic acids in the cells, in the same way as found previously from chemical studies in vitro, and with proteins. Iodoacetamide reacts only with protein, principally with the thiol groups of cysteine residues. 3. The extents of alkylation of cellular constituents required to prevent cell division vary widely according to the strain of bacteria and the nature of the alkylating agent. 4. The extents of alkylation of the sensitive and resistant strains at a given dose of alkylating agent do not differ significantly. 5. Removal of alkyl groups from DNA of cells of the resistant strains B/r and 15T(-) after alkylation with difunctional sulphur mustard was demonstrated; the product di(guanin-7-ylethyl) sulphide, characteristic of di- as opposed to mono-functional alkylation, was selectively removed; the time-scale of this effect suggests an enzymic rather than a chemical mechanism. 6. The sensitive strain B(s-1) removed alkyl groups from DNA in this way only at very low extents of alkylation. When sensitized to mustard action by treatment with iodoacetamide, acriflavine or caffeine, the extent of alkylation of cellular DNA corresponding to a mean lethal dose was decreased to approximately 3 molecules of di(guanin-7-ylethyl) sulphide in the genome of this strain. 7. Relatively large numbers of monofunctional alkylations per genome can be withstood by this sensitive strain. Iodoacetamide had the weakest cytotoxic action of the agents investigated; methyl methanesulphonate was significantly weaker in effect than the monofunctional sulphur mustard, which was in turn weaker than the difunctional sulphur mustard. 8. Effects of the sulphur mustards on nucleic acid synthesis in sensitive and resistant strains were studied. DNA synthesis was inhibited in both strains at low doses in a dose-dependent manner, but RNA and protein synthesis were not affected in this way. 9. DNA synthesis in E. coli B(s-1) was permanently inhibited by low doses of mustards. In the resistant strains 15T(-) and B/r a characteristic recovery in DNA synthesis was observed after a dose-dependent time-lag. This effect could be shown at low doses in the region of the mean lethal dose. 10. Cellular DNA was isotopically prelabelled and the effect of mustards on stability of DNA was investigated. With resistant strains a dose-dependent release of DNA nucleotide material into acid-soluble form was found; this was much more extensive with the difunctional mustard (about 400 nucleotides released per DNA alkylation) than with the monofunctional mustard (about 10 nucleotides per alkylation). With the sensitive strain no dose-dependent release was found, though the DNA was less stable independent of cellular alkylation. 11. The results are discussed in terms of the concepts that alkylation of cellular DNA induces lesions which interfere with DNA replication, but which can be enzymically ;repaired'. The possible nature of these lesions is discussed in terms of the known reactions of the alkylating agents with DNA.

110 citations


Journal ArticleDOI
TL;DR: At 95-115°, paraformaldehyde and hydriodic acid completely C-methylate aromatics such as benzene and phenol, carbethoxy and acetyl groups being lost as mentioned in this paper.
Abstract: At 95–115°, paraformaldehyde and hydriodic acid completely C-methylate aromatics such as benzene and phenol. Pyrroles are C-methylated similarly, carbethoxy and acetyl groups being lost. In hydriod...

83 citations


Journal ArticleDOI
TL;DR: While adenine units in native DNA are unreactive, in denatured DNA they react at a rate 5 times those in poly A, which is 7-fold greater than in monomeric guanine ribosides and ribotides.

77 citations






Journal ArticleDOI
TL;DR: It has been suggested, that L(—)α iodopropionic acid is specifically oriented onto the reaction center through the concerted attractive and repulsive actios of a cations and an anionic group in the protein.
Abstract: 1 When undergoing nucleophilic reactions with proteins, α-iodopropionic acid and its amide show greater specificity for SH groups than to inodoacetic acid and its amide. 2 The kinetics and sterochemistry of the reactions of the D(+) and L(—) antiopodes of α-iodopropionic acid and its amide with both eysteine and papain were investigated. The antipodes of the SH reagents reacted with these asymmetric SH compound at different rates. In the reaction with papain, the L(—) antipode of the acid reacted faster than the D(+) antipode; the stereochemical preference was inverted when the amide was used, the D(+)antipode reacting faster than the L(—)antipode. 3 Arguing from the differing reactivities of the SH reagents and their antipodes and the pH dependence of the reaction rates, it has been suggested, that L(—)α iodopropionic acid is specifically oriented onto the reaction center through the concerted attractive and repulsive actios of a cations and an anionic group in the protein. These have been tentatively identifid as a protonated imidazole residue and a carboxylate group respectively. 4 Parallels between these stereospecific alkylations and the catalytic action of the enzyme are discussed.


Journal ArticleDOI
TL;DR: In this paper, 14C-carboxamidomethyl peptides were isolated from pepsin digests and characterized sufficiently to identify them with certain of the cysteinyl peptide previously isolated and sequenced.


Patent
22 Aug 1968
TL;DR: NOVEL 2-AMINO-ADENOSINE DRIVATIVES CHARACTERIZED by CARDIAC and CIRCULATORY ACTIVITY and by their high Coronary SPECIFICITY HAVING the FOLLOWING STRUCTURAL FORMULA: 2-NH2,6-(R1-N(-R2)-),9-(3,4,5-TRI(HO-)-2-TTERAHYDRO- PYRanyL)-9H-PURINE whereIN R1 is HYDR
Abstract: NOVEL 2-AMINO-ADENOSINE DRIVATIVES CHARACTERIZED BY CARDIAC AND CIRCULATORY ACTIVITY AND BY THEIR HIGH CORONARY SPECIFICITY HAVING THE FOLLOWING STRUCTURAL FORMULA: 2-NH2,6-(R1-N(-R2)-),9-(3,4,5-TRI(HO-)-2-TETRAHYDRO- PYRANYL)-9H-PURINE WHEREIN R1 IS HYDROGEN, A SUBSTITUTED OR UNSUBSTITUDED, SATURATED OR UNSATURATED, STRAIGHT OR BRANCHED CHAIN ALIPHATIC HYDROCARBON RADICAL, WHEREIN SAID SUBSTITUENT IS AT LEAST ONE OF AMINO, ALKYLAMINO, DIALKYLAMINO, ACYLAMINO, ALKOXY, ACYLOXY, HYDROXY, MERCAPTO, ALKYLMERCAPTO, CARBOXY, CARBOXY ALKYL OR CARBOXAMIDO AND R2 IS A SATURATED OR UNSATURATED CYCLOALKYL RADICAL WHICH CAN CARRY ENDOALKYLENE RADICALS OR ANNELLATED, SATURATED OR UNSATURATED CYCLIC ALIPHATIC HYDROCARBON RADICALS, WHEREIN SAID SUBA-X-3, WHEREIN A IS A SUBSTITUTED OR UNSUBSTITUTED, SATURATED OR UNSATURATED, STRAIGHT OR BRANCHED CHAIN, OR CYCLIC ALIPHATIC HYDROCARBON RADICAL, WHEREIN SAID SUBSTITUENT IS AT LEAST ONE OF HYDROXY, ACYLOXY, CARBOXY AND ARYL RADICALS, X IS A VALENCY BOND, AN OXYGEN OR SULFUR ATOM, ALKYLATED IMINO OR ACYLATED IMINO, AND B IS A SUBSTITUTED OR UNSUBSTITUTED ALKYL, ALKENYL, ARYL, FURYL, PYRIDYL, INDOLYL OR IMIDAZOLYL RADICAL, WHEREIN SAID SUBSTITUENT IS AT LEAST ONE OF HALOGEN, ALKYL, HALOALKYL, ALKOXY, ARYLOXY, ACYLOXY, HYDROXY, MERCAPTO, ALKYLMERCAPTO, NITRO, CARBOXY, CARBOXYLALKYL AND METHYLSULFONYLAMINO RADICALS.

Patent
20 Feb 1968
TL;DR: New 3-SUBSTITUTED-1 - INDOLE- and 4,5,6,7 - TETRAHYDROINDOLE-LOWER-ALKANOIC ACIDS and ESTERS HAVING USEFUL ANTI-FLAMMATORY ACTIVITY and PREPARED by ALKYLATION of a 3 -Substituted -INDOLE with an APPROPRIATE HALO-LOWER-ALK ANNOIC ACID OR ESTER OR by CYCLIZATION OF a 2
Abstract: NEW 3-SUBSTITUTED-1 - INDOLE- AND 4,5,6,7 - TETRAHYDROINDOLE-LOWER-ALKANOIC ACIDS AND ESTERS HAVING USEFUL ANTIINFLAMMATORY ACTIVITY AND PREPARED BY ALKYLATION OF A 3 - SUBSTITUTED - INDOLE WITH AN APPROPRIATE HALO-LOWER-ALKANOIC ACID OR ESTER OR BY CYCLIZATION OF A 2-(2-R2-2-OXOETHYL) CYCLOHEXANONE OR 2-(1 -PHENYL-2-OXO-LOWER-ALKYL) CYCLOHEXANONE WITH AN AMINO ACID OR ESTER.



Journal ArticleDOI
TL;DR: This paper showed that 2,6-dialkyl-phenols exhibit little steric hindrance on reaction with phosphoryl chloride unless the alkyl substituent is bulky (i.e. t-butyl).
Abstract: 2,6-Dialkyl-phenols exhibit little steric hindrance on reaction with phosphoryl chloride unless the alkyl substituent is bulky (i.e. t-butyl). Where bulky substituents are present reaction with phosphoryl chloride occurs only in the presence of Friedel–Crafts type catalysts after either a dealkylation or a rearrangement of the ortho-placed alkyl groups, followed by O-phosphorylation, has occurred.


Journal ArticleDOI
TL;DR: The influence of neighboring groups on the course of the alkylation of ribonuclease has been studied with two derivatives in which lysine residues have been modified and the results eliminate the possibility that the positive charges on the e-NH2 groups of lysines-7 and lysin-41 have a role in the orientation of ICH2COO-.

Journal ArticleDOI
TL;DR: In this article, the relative proportions of mono and dialkylated products have been discussed, and various factors of interest in the control of mono versus dialkylation have been indicated, including selectivity of alkylation in liquid ammonia may be controlled by varying the amount of NaNH 2.


Journal ArticleDOI
TL;DR: A facile, general synthesis for a number of 5-substituted 1-methyluracils and cytosine which is suitable for the preparation of microquantities is reported in this paper.


Patent
E Bowes1
18 Apr 1968
TL;DR: In this article, a process for alkylating or dealkylating a compound capable of alkylation or denoising a compound by contacting it in a reaction zone maintained under conditions effective for accomplishing said alkylation with a catalyst comprising a crystalline zeolite characterized by a unique X-ray diffraction pattern or products of thermal treatment of the zeolate.
Abstract: A process for alkylating or dealkylating a compound capable of alkylation or dealkylation by contacting it in a reaction zone maintained under conditions effective for accomplishing said alkylation or dealkylation with a catalyst comprising a crystalline zeolite characterized by a unique X-ray diffraction pattern or products of thermal treatment of the zeolite. The zeolite can be further defined by reference to the following formula expressed in terms of mole ratios of oxides: WHEREIN M is a cation, J is aluminum or gallium and Z is silicon or germanium and n is the valence of M.

Journal ArticleDOI
TL;DR: In this article, it was proposed that these salts result from an intramolecular reaction of initially formed alkylation products, in which case the initial alkyl product undergoes an intramerolecular condensation with subsequent hydrogen chloride elimination.


Journal ArticleDOI
TL;DR: The nature and size of the target for alkylation and consequent inactivation of gene transcription and mRNA translation is discussed in the light of these results, and compared with the data obtained by other workers for inactivation by ultraviolet irradiation.

Journal ArticleDOI
TL;DR: Dehydroacetic acid with three equivalents of sodium amide converted it to a trianion which underwent condensations with electrophiles predominantly at the 6-Me position as discussed by the authors.