摘要:

The frequencies of the NO2symmetrical stretching vibrations, and the ultraviolet absorption spectra, of solutions of 9-nitroanthracene and 9,10-dinitroanthracene have been measured and correlated with the deviations from coplanarity and resultant resonance inhibition.

ISSN:0008-4042    

DOI:10.1139/v59-143

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

During the fermentation of glucose, sucrose, or lactose byBacilluspolymyxa, a mixture of polysaccharides is formed, one of which has been isolated by mild procedures and shown to contain mannose as the only sugar together with approximately 13% protein. Acid hydrolysis of the methylated mannan gave 2,3,4,6-tetra-O-methyl-D-mannose, 2,4,6-tri-O-methyl-D-mannose, 3,4,6-tri-O-methyl-D-mannose, and 3,4-di-O-methyl-D-mannose in the approximate ratio 2:1:1:2. Periodate oxidation results are in agreement with the methylation data and indicate a molecular weight of approximately 3000.

ISSN:0008-4042    

DOI:10.1139/v59-144

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

A synthesis of 5,6-dideoxy-L-arabino-hexose (II) from methyl β-D-galactofuranoside is described.

ISSN:0008-4042    

DOI:10.1139/v59-145

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

Air-saturated aqueous chloral hydrate has been irradiated with beta rays and the acid yield as determined by titration has been studied as a function of dose rate, temperature, and initial concentration of the chloral hydrate.The average lifetime of the intermediates has been found, by means of the rotating sector technique, to be about 0.5 second. Propagation and termination rate constants for the reaction have been calculated and an effort has been made to explain the results observed in terms of a free radical chain reaction.

ISSN:0008-4042    

DOI:10.1139/v59-146

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

A scheme of manual counter-current extraction, ingeniously devised, has facilitated quantitative isolation of initial products from autoxidized methyl linoleate under controlled conditions. A sole product of monomeric monohydroperoxide with one spatial configuration has been shown to be the outcome of interactions of oxygen molecule with methyl linoleate. The physical and chemical analyses prove this product as conjugatedcis,transmethyl linoleate hydroperoxide. The fractionations of its derivative, hydroxystearic acid, and its scission products go to establish the formation of two positional isomers (9- and 13-) exclusively for thiscis,transproduct. Such positional isomers leave no doubt about two possibilities of attack by oxygen on the two 3-C segments in the 5-C system of methyl linoleate containing mobile π electrons. A mechanism has been proposed relevant to the experimental findings. Such initiation processes offer the missing link between neutral methyl linoleate and formation of its hydroperoxide without decomposition. These investigations, thus, emphasize the fact that the initiation processes must be distinguished from the main autoxidation reactions.

ISSN:0008-4042    

DOI:10.1139/v59-147

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

Slater's theory of unimolecular reactions is tested by comparing theoretical and experimental values of the pressure at which the rate constant has fallen off from the high-pressure limit by 5%. A simplified method is used for calculating lower bounds to the theoretical value of this pressure. Agreement with experimental data on cyclobutane, cyclobutene, and nitrogen pentoxide is rather poor; experimental values are lower than the calculated lower bounds.

ISSN:0008-4042    

DOI:10.1139/v59-148

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

A chloroform-soluble, neutral wax was isolated from the leaves of Colorado spruce, collected during fall and winter months. The wax was found to consist of sabinic, 14-hydroxytetradecanoic, and juniperic acids, with only minor amounts of non-saponifiables andn-fatty acids. 14-Hydroxytetradecanoic acid has not been found before in naturally occurring waxes. A cyclic structure rather than the linear etholides proposed for other conifer waxes is in accord with the analytical data. In the spring and summer months the wax was accompanied by an acidic fraction.

ISSN:0008-4042    

DOI:10.1139/v59-149

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

In an attempt to find the precursor of the piperidine ring in homostachydrine, young alfalfa shoots were fed (a) lysine-2-14C, (b) lysine-2-14C with pyridoxine, (c) lysine-2-14C with pyridoxine and folic acid, and finally (d) lysine-2-14C with pyridoxine, folic acid, and miethionine. In all cases the homostachydrine isolated from the harvested plants showed no radioactivity. It is shown that homostachydrine is not synthesized at the stage of growth at which the experiments were carried out. Alfalfa has been found to contain a hitherto unreported alkaloid shown to be trigonelline by comparison with an authentic sample. Both homostachydrine and trigonelline are found in the seeds, and are not actively synthesized in the plant until seed formation. Asparagine has also been isolated in relatively high yield.

ISSN:0008-4042    

DOI:10.1139/v59-150

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

In the displacement reaction with sodium iodide in acetic anhydride solution the rates of reaction of four isohexide tosyl esters were compared to that of anO-acetyl-O-tosylisosorbide recently described. The tosyloxy group in the latter compound was replaced rapidly and was therefore in the 5-endo-position, the compound being correctly named2-O-acetyl-5-O-p-toluenesulphonyl-1,4;3,6-dianhydro-D-glucitol. The product of the reaction was isolated as a crystalline material, and was identified as2-O-acetyl-5-deoxy-5-iodo-1,4;3,6-dianhydro-L-iditol.

ISSN:0008-4042    

DOI:10.1139/v59-151

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

Recent determinations of the ionization potentials of methylamines and ethylamines obtained by electron impact have been compared with photoionization results and discussed in relation to the Franck–Condon principle. It seems that the observed discrepancies are mainly due to differences in the sensitivities of the detecting devices.

ISSN:0008-4042    

DOI:10.1139/v59-152

出版商:NRC Research Press    

年代:1959

数据来源: NRC