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Showing papers on "Diazomethane published in 1985"


Journal ArticleDOI
TL;DR: The antibiotics isolated from soil samples collected from the fields around Lewiston, Idaho showed inhibitory activity against several species of bacteria, especially Treponema hyodysenteriae, the causative agent of swine dysentery, and may have value as a swine Dysentery therapeutic.
Abstract: Two strains of Streptomyces sp. (isolates 275 and 124) were isolated from soil samples collected from the fields around Lewiston, Idaho. Based on their cellular morphology and physiology, the two isolates were identified as Streptomyces albovinaceous. Both isolates produced an antibiotic when grown in liquid culture medium containing homogenized oats. The antibiotic (treponemycin) was isolated from the culture broth by solvent extraction and purified by silica gel column and preparative thin-layer chromatographies. Treponemycin is a crystalline light-yellow compound with an mp of 93 to 95 degrees C, levorotatory, and soluble in most organic solvents. It is sparingly soluble in water but insoluble in petroleum ether. On the basis of elemental analysis and mass spectral data, the molecular formula of the antibiotic was deduced to be C28H43O6N. The infrared spectrum of the antibiotic indicated the presence of unsaturation, nitrile, lactone, or ester or all three functions, and carbonyl functions in the molecule. A sharp infrared absorption band for nitrile at 2,220 cm-1 and the presence of an unsaturated group indicated that the nitrile function may be attached to an unsaturated carbon atom. The presence of dienenitrile functions was further supported by the UV absorption spectrum of the antibiotic, which gave a UVmax at 257 nm. The proton magnetic resonance spectrum of the antibiotic did not give any peak which could be exchanged with deuterated water, which is an indication of the absence of carboxylic and hydroxyl functions in the molecule. All of the functional groupings indicated by the infrared and UV spectra of the molecule were further confirmed by the 13C-magnetic resonance spectrum of the compound. A brief hydrogenation of the antibiotic yielded a biologically active tetrahydro derivative, whereas extended hydrogenation produced an inactive primary amine. Mild alkaline hydrolysis and subsequent esterification of the antibiotic with diazomethane produced an inactive dimethyl ester. Apparently both the nitrile and the lactone functions are essential for the treponomycin molecule to show antimicrobial activity. The antibiotic showed inhibitory activity against several species of bacteria, especially Treponema hyodysenteriae, the causative agent of swine dysentery. In view of the oral 50% lethal dose of 400 mg/g and its low MIC against four stains of T.hyodysenteriae, the antibiotic may have value as a swine dysentery therapeutic.

45 citations


Journal ArticleDOI
TL;DR: The title reaction affords the two regioisomeric cycloadducts which were isolated and differ in their rates of nitrogen extrusion; the spiro-1,3,4-thiadiazoline furnishes the adamantanethione S-methylide which undergoes in situ cycloadditions to electron-deficient dipolarophiles.

30 citations



Journal ArticleDOI
TL;DR: In this article, photolysis of diazomethane in (S)-2-methyloxetane gives 2- and 3-methyltetrahydrofuran (1:3.2), the latter being formed with 21 % net retention of configuration.

27 citations


01 Jan 1985
TL;DR: 2'-O-Methyl derivatives of common ribonucleosides were prepared from appropriately protected nucleosides via the methylation of the 2'-hydroxyl groups with methyl iodide or diazomethane and synthesized in a stepwise manner by using the phosphotriester method.
Abstract: 2'-O-Methyl derivatives of common ribonucleosides were prepared from appropriately protected nucleosides via the methylation of the 2'-hydroxyl groups with methyl iodide or diazomethane. These derivatives were converted into 2'-O-methylribonucleotide units and the guanosine derivative was linked to a polymer support. Thus, oligo(2'-O-methylribonucleotides) having the sequence of AmCmUmUmAmCmCmUmGm was synthesized in a stepwise manner by using the phosphotriester method. Thermal stabilities (Tm's) of the hybrid between the 2'-O-methyl ribooligomer and the complementary ribooligomer and of the related hybrids are compared. The synthesis of ribooligomer by a new approach is also described.

19 citations


Journal ArticleDOI
TL;DR: The cycloaddition reaction of diazomethane with diethyl 1,3-butadienylphosphonates containing electronegative substituents on the α-carbon atom gave Diethyl (4-alkenyl-Δ1-pyrazolin-3-yl)phosphonsates in high yields as mentioned in this paper.
Abstract: The cycloaddition reaction of diazomethane with diethyl 1,3-butadienylphosphonates containing electronegative substituents on the α-carbon atom gave diethyl (4-alkenyl-Δ1-pyrazolin-3-yl)phosphonates in high yields. Thermolysis and the base-catalyzed reaction of the pyrazolinylphosphonates produced functionalized 2,4-pentadienylphosphonates and pyrazoles, respectively, in good yields.

19 citations


Journal ArticleDOI
TL;DR: Several Z-2-methyl(or phenyl)-4-[α-arylethylidene]-5(4H)-oxazolones 3Z, 4Z were prepared by diazomethane insertion and condensation procedure as mentioned in this paper.

18 citations


Journal ArticleDOI
TL;DR: All metabolites reported in this study were formed from oxidized felodipine by ester hydrolysis and represented an important metabolic pathway and metabolites oxidized to the corresponding carboxylic acids were detected as well.
Abstract: After intragastric administration of 100 mumol kg-1 [14C]felodipine to rats eight urinary metabolites were isolated. Batch extraction at pH 2.2 and semipreparative reversed-phase liquid chromatography were used for trace enrichment of the metabolites. Trimethylsilylation followed by transesterification with diazomethane blocked the carboxylic acid and alcohol groups selectively before gas chromatography/mass spectrometry (GC/MS) in the electron impact (EI) mode. Deuterated derivatives of the metabolites and chemical ionization measurements added complementary structural information. All metabolites reported in this study were formed from oxidized felodipine by ester hydrolysis. Hydroxylation of the pyridine methyl group represented an important metabolic pathway and metabolites oxidized to the corresponding carboxylic acids were detected as well. Lactone formation from hydroxy acid metabolites in urine as a possible analytical artefact is discussed.

18 citations


Journal ArticleDOI
TL;DR: Cycloaddition dipolaire-1,3 du diazomethane conduisant a des pyrazolines-1(I). La pyrolyse de (I) donne stereoselectivement les Z-(acylamino-2 phenyl-3) butene-2oates de methyle as mentioned in this paper.
Abstract: Cycloaddition dipolaire-1,3 du diazomethane conduisant a des pyrazolines-1(I). La pyrolyse de (I) donne stereoselectivement les Z-(acylamino-2 phenyl-3) butene-2oates de methyle

18 citations


Journal ArticleDOI
TL;DR: An inverse isotope dilution method has been developed to determine both enantiomers of the drug in biological fluids after administration of 14C-labelled oxindazac and no racemization is observed upon methylation to the corresponding methyl ester with diazomethane.

17 citations


Journal ArticleDOI
TL;DR: In this article, the decomposition of diazomethane over zeolite ZSM-5 gives ethene and propane as the major products; this supports the existence of carbenoid intermediates proposed in methanol conversion into higher hydrocarbons over this catalyst.
Abstract: Decomposition of diazomethane over zeolite ZSM-5 gives ethene and propane as the major products; this supports the existence of carbenoid intermediates proposed in methanol conversion into ethene and higher hydrocarbons over this catalyst

Journal ArticleDOI
TL;DR: In this article, the reaction of diazomethane with a series of selenoesters in the presence of CuI, CuSePh or Cu powder produced α-(alkyl- or arylseleno)methyl ketones in yields of 41-65%.

Journal ArticleDOI
TL;DR: In this paper, a working hypothesis is proposed to describe the mechanism of this reaction, and it is shown that after esterification with diazomethane, (R)-1-naphthylglycolic acid methyl ester (4c) in 9.7% ee.
Abstract: Reduction of 1-naphthylglyoxylic acid (2c) by inclusion complex formation with optically active paracyclophane (1a) followed by treatment with sodium borohydride in acidic water gave, after esterification with diazomethane, (R)-1-naphthylglycolic acid methyl ester (4c) in 9.7% ee. A working hypothesis is proposed to describe the mechanism of this reaction.

Journal ArticleDOI
TL;DR: In this paper, the insertion reaction of benzenesulfenyl thiocyanate (3) with trimethylsilyl isothiocynate (4) was studied.

Journal ArticleDOI
TL;DR: In this article, Diazomethane degradation of regiospezifically formed 2,2′-bi-1,4-naphthoquinones (20, 21) with knowledge of their behaviour was determined and correlated with predictions from HMO calculations.

Journal ArticleDOI
TL;DR: In this article, the reaction of dichloro(2,2, N,N -tetramethyl-3-buten-1-amine)palladium(II) with diazomethane in ether/ethanol leads to the carbene insertion product, a -chloro- b -(chloromethyl)- d,c -( 2,2.N,N-tetramerethyl- 3-butens-1 -amine) palladium (II) and the analogous ethoxymethyl and methyl complexes.

Journal ArticleDOI
TL;DR: The fate of benzoic acid was studied in 7 species of marsupials and the echidna and it was found that all species excreted most of the dose in 24 hr, while Benzoyl glucuronide excretion varied greatly, from 2% of the doses in the pademelon to 32% in sugar gliders.
Abstract: The fate of benzoic acid was studied in 7 species of marsupials and the echidna. Radiolabelled [7-14C]-benzoic acid was administered to 3-7 animals of each marsupial species (brown bandicoot, barred bandicoot, Tasmanian devil, potoroo, pademelon, brush-tailed possum and sugar glider) and urine was collected over ice for 24 hours. Metabolites were extracted from acidified urine with ethyl acetate and separated on fluorescent silica gel TLC plates. Bands were visualised under UV, and eluted with methanol. After methylation with diazomethane, benzoic acid, hippuric acid and β-hydroxyphenylpropionic acid were identified by GC/MS. The methylated benzoyl glucuronide required trimethylsilylation before GC/MS. Quantification was by liquid scintillation spectrometry. It was found that all species excreted most of the dose in 24 hr. As with eutherians, the major metabolite was hippuric acid, with smaller amounts of benzoic acid and β-hydroxyphenylpropionic acid. Benzoyl glucuronide excretion varied greatly, from 2% of the dose in the pademelon to 32% in sugar gliders. Similar variability has also been reported in eutherians.

Journal ArticleDOI
Claus O. Meese1
TL;DR: In this article, the synthesis of two new fluorinated diazoalkanes 2a and b was described, and the two new diazomethanes were described as follows:

Journal ArticleDOI
TL;DR: In this article, the reaction of dichloro- and diiodo-(1,5-cyclooctadiene)platinum(II) with excess diazomethane affords the corresponding air-stable bis(halomethyl) complexes Pt(CH 2 X) 2 (COD) (X = Cl or I) in excellent yield.

Journal ArticleDOI
TL;DR: Using deuterated reagents in the sample preparation procedure during the organic acid analysis, it is shown that the N- methylated and N,N-dimethylated amino acids are artifacts from diazomethane and are not biochemical N-methylation products.

Journal ArticleDOI
TL;DR: The 3-trimethylsilyl-1-pyrazoline was synthesized by adding diazomethane to vinyl trimethylsilane at room temperature as mentioned in this paper.

Patent
24 Sep 1985
TL;DR: In this paper, a crystalline diazomethane derivative of the formula: R, and R 2 are, the same or different, substituted or unsubstituted aromatic group is prepared by a process comprising concentrating and drying a solution of the derivative in an organic solvent under reduced pressure at a temperature not higher than 30°C while applying shearing force on a viscous cake.
Abstract: A crystalline diazomethane derivative of the formula: wherein R, and R 2 are, the same or different, a substituted or unsubstituted aromatic group is prepared by a process comprising concentrating and drying a solution of the diazomethane derivative in an organic solvent under reduced pressure at a temperature not higher than 30°C while applying shearing force on a viscous cake.

Journal ArticleDOI
TL;DR: In this article, the authors showed that methylation of 4-styryltropolones with diazomethane afforded 2-methoxy-4-styltroyltropones (2a-g) and 2methoxylstyltropolone derivatives 5a−g.
Abstract: The methylation of 4-styryltropolones with diazomethane afforded 2-methoxy-4-styryltropones (2a–g) and 2-methoxy-6-styryltropones. The reactions of 2a–g with hydrazine gave 2-hydrazino derivatives, which were converted to 2-chloro derivatives 5a–g. Ammonolysis of 5a–g afforded 2-amino-5-styryltropones (7a–g) by cine substitution reaction. The compounds 7a–g were hydrolyzed to give the corresponding 5-styryltro-polones. Some interesting by-products were also found in these synthetic processes.


Journal ArticleDOI
TL;DR: 1,3-Cycloaddition of diazomethane and ethyl diazoacetate to Δ15-17-ketoandrostane proceeds regio- and stereospecifically from the β-region of the steroid molecule, and the pyrazolinoandrostanes obtained were converted into the corresponding 15β,16β-cyclopropane derivatives.
Abstract: 1,3-Cycloaddition of diazomethane and ethyl diazoacetate to Δ15-17-ketoandrostane proceeds regio- and stereospecifically from the β-region of the steroid molecule, The pyrazolinoandrostanes obtained were converted into the corresponding 15β,16β-cyclopropane derivatives.

Journal ArticleDOI
TL;DR: In aqueous solutions (with or without salts) containing carboxylic acids, water can be bound with anhydrous sodium sulphate at a molar ratio of [Na2SO4]/[H2O] ⩾ 0.9 as mentioned in this paper.

Journal ArticleDOI
TL;DR: Methode de Penzhorn et Filby (1976) modifiee, basee sur la formation de diazomethane and la methylation de l'acide sulfurique as mentioned in this paper.
Abstract: Methode de Penzhorn et Filby (1976) modifiee, basee sur la formation de diazomethane et la methylation de l'acide sulfurique. Seuil de detection de H 2 SO 4 :3 ng. Application a des mesures au Japon

Patent
21 Jan 1985
TL;DR: In this article, the diazomethane derivative of formula (R1 and R2 are substituted or unsubstituted aromatic group) is mixed with methylene chloride at a weight ratio of (100-25):(0-75), and stored at -25-+15 deg.C.
Abstract: PURPOSE:To store the titled compound useful as a carboxyl-protecting group of organic compounds, easily, at a low cost, in high stability, by mixing a diazomethane derivative with methylene chloride at a specific ratio, and storing the mixture at a specific temperature. CONSTITUTION:The diazomethane derivative of formula (R1 and R2 are substituted or unsubstituted aromatic group) is mixed with methylene chloride at a weight ratio of (100-25):(0-75), and stored at -25-+15 deg.C, preferably, -20- +10 deg.C. Although diazomethane derivative is useful as a protecting group of the carboxyl of organic compounds, it is decomposed extremely easily, for example, diphenyldiazomethane is decomposed to ketazine when left at room temperature for 2 days, and the purity decreases to 75% of the original purity. It has been found that the decomposition rate of the compound can be decreased remarkably when the diazomethane derivative is stored in a state containing at least part of the diazomethane derivative in the form of crystal and in the presence of methylene chloride.

Journal ArticleDOI
TL;DR: In this paper, 5.5-O and 6-O-Methyldihydro-streptomycin were obtained from dihydro-stomycin by a sequence of reactions involving methylation of a selectively protected derivative (4) with diazomethane in the presence of tin(II) chloride.
Abstract: 5-O- and 6-O-Methyldihydrostreptomycin have been prepared from dihydrostreptomycin by a sequence of reactions involving methylation of a selectively protected derivative (4) with diazomethane in the presence of tin(II) chloride. The structures of the final products were confirmed by their 13C-NMR spectra and the TACu method.

Journal ArticleDOI
TL;DR: In this article, a combination of chemical pretreatments, capillary gas-chromatography and mass spectrometry was used to enlighten the structure of atypical fatty acids with cyclopropane rings under the use of only a few of reference substances.
Abstract: By combined application of chemical pretreatments, capillary gas-chromatography and mass spectrometry it was possible to enlighten the structure of atypical fatty acids with hydroxy groups and cyclopropane rings under the use of only a few of reference substances. The direct alkaline saponification of the sample with liberation of fatty acids and following methylation with boron trifluoride/methanol or diazomethane was proved to be the best method regarding to precision and speed of the sample cleanup.