摘要:

The molecular weights of horse hemoglobin, horse globin, and performic acid oxidized horse globin were determined by osmotic pressure, by an approach to equilibrium sedimentation, and by light scattering (except hemoglobin) at pH 1.5 to 2.5 in 0.05 MNaCl. Sedimentation coefficients were determined for these materials over the same pH range and electrophoretic analyses were made from pH 1.5 to 4.0. The results show that in dilute salt solutions below pH 2.5 horse hemoglobin dissociates to four subunits all approximately equal in mass but at least two of which differ electrokinetically and therefore in composition. The subunits are probably held together in the native hemoglobin molecule only by non-covalent bonds.

ISSN:0008-4042    

DOI:10.1139/v56-060

出版商:NRC Research Press    

年代:1956

数据来源: NRC

摘要:

The following compounds were thought to be new: 1,2-mono-O-isopropylidene-D-glucofuranose-3-S-methyl xanthate, m.p. 102°,−27.8°; methyl-4,6-O-benzylidene-α-D-glucopyranoside-2,3-di-S-methyl xanthate, m.p. 100°,−18.1°; and 1,2;3,5-di-O-methylene-α-D-glucofuranose-6-S-methyl xanthate, m.p. 99°,+27.3° in chloroform. Partial hydrolysis of the isopropylidene and methylene derivatives yielded some glucose-3-S-methyl xanthate and glucose-6-S-methyl xanthate as crude sirups. The 6-xanthate greatly excelled the 3-xanthate in stability toward acid. The chromatographic behavior of both was determined.

ISSN:0008-4042    

DOI:10.1139/v56-061

出版商:NRC Research Press    

年代:1956

数据来源: NRC

摘要:

A synthetic procedure is described that gives in excellent yield pure phosphorylethanolamine. Its X-ray diffraction pattern and infrared spectrum are reported.

ISSN:0008-4042    

DOI:10.1139/v56-062

出版商:NRC Research Press    

年代:1956

数据来源: NRC

摘要:

The possibility that neutron capture would lead to oxidation, because of internal conversion of the capture radiation, has been investigated in solid compounds of the lower valence states of antimony, arsenic, cerium, chromium, and thallium. Except in the hydrated compounds, negative results have been obtained. It is possible that oxidation is followed by electron-transfer exchange in the irradiated solids.

ISSN:0008-4042    

DOI:10.1139/v56-063

出版商:NRC Research Press    

年代:1956

数据来源: NRC

摘要:

Failure to consider the presence of up to 16% by volume of methanol in solutions of dextran fractions had a very marked effect onapparentintrinsic viscosity determinations (the termapparentsignifies that measurements were made assuming that the solvent was water only). Unless methanol were removed or otherwise taken into account, high erroneous results were obtained.Apparentweight average molecular weights determined by light scattering were not significantly affected at these alcohol concentrations. The relations found over the range 0 to 16% methanol for dextran samples with weight average molecular weights of 265,000, 155,000, and 72,000 held for the latter sample up to 44% methanol. In the higher range of alcohol concentration theapparentweight average molecular weight was depressed. The true intrinsic viscosity of dextran solutions decreased as methanol concentration was increased.

ISSN:0008-4042    

DOI:10.1139/v56-064

出版商:NRC Research Press    

年代:1956

数据来源: NRC

摘要:

Lead tetraacetate oxidation is shown to be useful for examining some structural features of trisaccharides and higher oligosaccharides. Generally, the oxidations follow a course similar to that found with the corresponding disaccharide. In some oligosaccharides, however, glycol groups which resist oxidation are encountered. Such groups are 2,3-transglycols of central residues which are linked to adjacent residues by 1,4-glycosidic bonds. The apparent inability to complex with lead tetraacetate suggests a conformation for these sugar residues in acetic acid solution which differs from that of the corresponding monosaccharide glycopyranoside. Lead tetraacetate oxidation of oligosaccharides in which central residues are unaffected by the reagent constitutes a unique stepwise degradation of these compounds, and possible applications of the reaction are suggested.

ISSN:0008-4042    

DOI:10.1139/v56-065

出版商:NRC Research Press    

年代:1956

数据来源: NRC

摘要:

l-Pusilline is shown to be identical with β-isosparteine by direct comparison of the bases and of their salts. By mild oxidation with mercuric acetate followed by catalytic hydrogenation, pusilline is converted tod-sparteine, thus confirming its identity withl-β-isosparteine. The sparteine obtained from β-isosparteine derived from lupanoline wasd-sparteine, and not thel-form as reported. Oxidation of β-isosparteine with potassium permanganate gives rise to a hydrated 10,17-dioxo-derivative.

ISSN:0008-4042    

DOI:10.1139/v56-066

出版商:NRC Research Press    

年代:1956

数据来源: NRC

摘要:

The fatty oil of delphinium seed (Delphinium hybridum(Hort.)) was examined. Fresh seed gave an oil composed mainly of glycerides but having 2.8% of free fatty acids. The oil from older seed contained about 50% of free fatty acids, apparently as a result of lipase action in the seed. The total fatty acids were found to includecis-11-eicosenoic acid (18%) and eicosadienoic acid (1%), the latter identified as tetrahydroxyeicosanoic acid. Other acids that were identified and the estimated percentages were: 9-hexadecenoic <1, palmitic 4, linoleic 16, oleic 53, and stearic 1. Spectroscopic analysis indicated a content of 2.5% of octadecatrienoic acid. Eicosoic acids have not been observed previously in the seed oils of this plant family (Ranunculaceae).

ISSN:0008-4042    

DOI:10.1139/v56-067

出版商:NRC Research Press    

年代:1956

数据来源: NRC

摘要:

The decomposition of sodium hypochlorite has been re-examined. The results show that Foerster and Dolch’s mechanism of the decomposition to chlorate and chloride is correct; they postulated a slow bimolecular reaction to chlorite and chloride, followed by a faster reaction of chlorite with more hypochlorite. Values of the rate constants of both steps are reported; they make the activation energies 24.8 kcal./gm-molecule for the first step and 20.8 kcal./gm-molecule for the second. The rates are such that at 40 °C. a solution of sodium hypochlorite will contain about 1% as much chlorite as hypochlorite. The rate is strongly affected by changing ionic strength; at low ionic strengths it is nearly constant or falls slightly; above about 0.8, the rate rises and at high ionic strengths the rise is quite rapid. No signs of specific catalytic effects of sodium chloride, hydroxide, or carbonate could be observed, and it seems probable that earlier reports of this were due to variations in ionic strength. The decomposition to chloride and oxygen has been measured and is a unimolecular reaction, which is possibly, but not certainly, uncatalyzed. Values of its rate constant are reported; they also are much altered by changing the ionic strength.

ISSN:0008-4042    

DOI:10.1139/v56-068

出版商:NRC Research Press    

年代:1956

数据来源: NRC

摘要:

The catalyzed decomposition of sodium hypochlorite has been examined; the catalysts tried were manganese, iron, cobalt, nickel, and copper oxides. It was shown that in no case was the decomposition to chlorate and chloride accelerated, only the reaction to chloride and oxygen. Manganese and iron did not catalyze even the latter reaction, or only to a very small extent; this was in fairly concentrated sodium hypochlorite containing some sodium hydroxide. The manganese and iron are largely oxidized to permanganate and ferrate under these conditions. It was found that copper could catalyze the formation of permanganate and ferrate, and nickel the formation of permanganate. Cobalt catalyzed the reaction going to oxygen, and the rate was proportional to the cobalt added, but little dependent on the hypochlorite concentration; the same is true of nickel. Copper (as reported earlier) gives a catalyzed reaction not far from first order in hypochlorite. The activation energies were measured, and were consistent with the relative catalytic activity of these metals. The mechanism of the reaction is briefly discussed.

ISSN:0008-4042    

DOI:10.1139/v56-069

出版商:NRC Research Press    

年代:1956

数据来源: NRC