摘要:

The kinetics of the iodination of several aminochromes by iodine in aqueous potassium iodide, to form the 7-iodo derivatives, have been studied. The rate of iodination is directly dependent on the concentrations of the aminochrome and iodine and varies inversely with the first power of the iodide ion concentration. The rate of reaction is independent of pH, but the reaction is subject to general base catalysis. A mechanism for the iodination of aminochromes is proposed. The reactive species are molecular iodine and the zwitterionic form of adrenochrome, and the reaction proceeds via a quinonoid intermediate. The rate-controlling process is the removal of the C-7 proton.

ISSN:0008-4042    

DOI:10.1139/v67-280

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

A new preparative procedure forN-(diazoacetyl)glycine ethyl ester is described. The interaction ofN-(diazoacetyl)glycine ethyl ester with four phenoxyacetyl chlorides gives the 4-phenoxylderivatives ofN-(2-diazo-3-oxobutanoyl)glycine ethyl ester, and with β-(o-methoxyphenoxy)-propionyl chloride yieldsN-[2-diazo-3-oxo-5-(o-methoxyphenoxy)pentanoyl]glycine ethyl ester. A general chromatographic procedure for separatingN-(2-diazo-3-oxoalkanoyl)glycine ethyl esters fromN-(chloroacetyl)glycine ethyl ester has been developed. Crotonyl chloride reacts with a 1 mole excess ofN-(diazoacetyl)glycine ethyl ester to formN-(2-diazo-3-oxo-4-hexenoyl)glycine ethyl ester, and with a 2 mole excess to formN-{2-diazo-3-oxo-3-[4′-methyl-5′(carboethoxymethyl)carbamoyl-Δ2pyrazolin-3′-yl]propanoyl}glycine ethyl ester, presumably by isomerization of an initially formed Δ1-pyrazoline derivative. The interaction of benzoyl andm-bromobenzoyl bromide withN-(diazoacetyl)glycine ethyl ester results initially in yellow oily products which, on the basis of spectral data, are the expectedN-(2-diazo-3-oxo-3-rylpropanoyl)glycine ethyl esters. During chromatographic purification and (or) attempted crystallization, there occurs an isomerization to colorless crystalline products. The analytical and molecular weight data, together with the spectral evidence, support the tentative assignment of 1,2,3-triazole structures to the isomerization products. A spontaneous reverse Dimroth rearrangement is postulated.

ISSN:0008-4042    

DOI:10.1139/v67-281

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

A series of new compounds has been prepared by reacting aliphatic and aromatic aldehydes with ethylene dithiosemicarbazide. The nature of these new dithiosemicarbazones has been deduced from their infrared spectra, from the products of the ferric chloride induced oxidation of two of them, and from the formation of 1:1 copper complexes of several of them. Since the copper complexes are paramagnetic, the copper must be present in the cupric oxidation state. A structure has therefore been proposed for the complexes which involves bonding between copper and both thiocarbonyl groups in the dithiosemicarbazone molecule.Several of the compounds prepared in this work exhibit an antifungal action against the cellulolytic microorganismChaetomium globosum.

ISSN:0008-4042    

DOI:10.1139/v67-282

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Careful fractionation of extracts prepared from barley coleoptiles gave small amounts of pure hordatines A and B and substantial amounts of a mixture of their glucosides. The structures of the hordatines were deduced by degradative and spectroscopic studies and by the synthesis of some degradation products. A synthesis of racemic hordatine A analogous to its probable biogenesis was achieved by the oxidative coupling of coumaroylagmatine.The possible role of the hordatines in lignification is briefly discussed.

ISSN:0008-4042    

DOI:10.1139/v67-283

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Several new β-hydroxyketones having the formula CH3R′C(OH)CH2COCH3have been prepared by the action of Grignard reagents on 2,4-pentanedione. With benzyl-,o-xylyl-,p-xylyl-, 3,4-dimethylbenzyl-, 2,5-dimethylbenzyl-, 3,5-dimethylbenzyl-, and α-naphthylmethyl-magnesium chlorides, 60 to 75% yields of the β-hydroxyketones were obtained. Phenyl-,p-tolyl-, andp-trifluoromethylphenyl-magnesium bromide and 2,4-dimethylbenzylmagnesium chloride gave lower yields, whereas with α-naphthylmagnesium bromide no β-hydroxyketone was formed. The β-hydroxyketones were separated from non-ketonic by-products by means of Girard's reagent T or P. Solid derivatives of the β-hydroxyketones could not be prepared.

ISSN:0008-4042    

DOI:10.1139/v67-284

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Methyl 4,6-O-ethylidene-3-O,S-dimethyl-2-thio-α-d-altropyranoside, when heated in refluxing 1,2-dimethoxyethane with an equimolar quantity of metallic sodium, gave approximately a 75% yield of a mixture of the three olefins, methyl 2,3-didehydro-3-deoxy-4,6-O-ethylidene-S-methyl-2-thio-α-d-altropyranoside (XI), l,2-didehydro-l-deoxy-4,6-O-ethylidene-3-O,S-dimethyl-2-thio-d-ribo-hexopyranose (XII), and methyl 3,4-didehydro-3-deoxy-4,6-O-ethylidene-S-methyl-2-thio-α-d-erythro(orthreo)-hexopyranoside (XIII) (tentative). Only compounds XI and XII could be separated and characterized. The structural assignments were based on a comparison with authentic samples and on nuclear magnetic resonance and infrared data, as well as on a comparison with the characteristics of analogous 4,6-O-benzylidene compounds previously reported (2).

ISSN:0008-4042    

DOI:10.1139/v67-285

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

The acid-catalyzed reaction of glyoxal at the ortho position of phenols has been shown to yield, as initial products, substituted 5a,10b-dihydrobenzofuro[2,3-b]benzofurans, such structures being indicated by the nuclear magnetic resonance spectra, and confirmed in several cases by synthesis via an unambiguous route. At higher temperatures in acidic media, and in the absence of glyoxal, these initial products were converted into the corresponding 2-(3-benzofuranyl)phenols. When glyoxal was present in acidic media, the 2-(3-benzofuranyl)phenols reacted further to give unidentified products of appreciably higher molecular weight.

ISSN:0008-4042    

DOI:10.1139/v67-286

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Contrary to previous reports, the reaction between acetophenone anil and sodium produces a product containing one atom of sodium per mole of anil. In its chemical behavior, this adduct appears to consist of equal parts ofN-sodio-N,1-diphenylethylamine and α-sodioacetophenone anil. Thus, treatment with an alkyl halide results in products derived by alkylation of the nitrogen atom ofN,1-diphenylethylamine and alkylation of the methyl group of acetophenone anil.The behavior of acetophenone anil towards lithium is quite different and very solvent dependent. In ether, hydrolysis of the lithium adduct produces a dimer,N,N′,2,3-tetraphenyl-2,3-butanediamine. In tetrahydrofuran with either lithium or potassium, another dimer,N,N′,l,4-tetraphenyl-1,4-butanediamine, is formed by dimerization through the methyl group of acetophenone anil. The structure of this new dimer was established by separation of the diastereomers and cyclization of each to the corresponding 1,2,5-triphenylpyrrolidine.The mechanism by which these products are formed is discussed.

ISSN:0008-4042    

DOI:10.1139/v67-287

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

JoHFand (JoHF + JmHF) in some substituted flurobenzenes increase algebrically as the dielectric constant of the medium increases. Benzene solvent also causes a substantial increase in these parameters.JpHH,JpHF,JmHH, and (probably)JmFFare independent of solvent. Because (JoHF – JmHF) normally lies between 2 and 3 c/s, deceptively simple spectra often occur because of the magnitudes of the other coupling constants involved. A substituent X, whose electronegativity (EX) is greater thanEH, reduces (JoHF + JmHF) if it is para to F, but increases (JoHF + JmHF) if it is ortho or meta to F. There is a need for accurate studies under controlled solvent conditions if patterns in substituent effects are to be observable.

ISSN:0008-4042    

DOI:10.1139/v67-288

出版商:NRC Research Press    

年代:1967

数据来源: NRC

ISSN:0008-4042    

DOI:10.1139/v67-289

出版商:NRC Research Press    

年代:1967

数据来源: NRC