bluuebunny/crossref_metadata_2025 huggingface dataset:
Copolymerization of drying oils
Authors: Boelhouwer C. , Tien Liem Tjing , Waterman H. I.
Published: September 2010

Unsaturated hydrocarbons were prepared from methyl esters of stearic, oleic, linoleic, and linolenic acid, and from linseed oil fatty acid methyl esters, by replacing the ester group by an alkene group (reaction of the esters with alkyl magnesium halide and dehydration of the tertiary alcohols formed).

These olefins show the same polymerization phenomena as do the esters from which they are derived. Thermal polymerization of olefins derived from methyl linoleate and methyl linolenate leads to monocyclic and bicyclic dimers, respectively, in accordance with the results of polymerization of the corresponding esters.

Copolymerization of tung oil with olefins prepared from linseed oil fatty acid esters only occurs at higher temperatures (275° C); the reaction is promoted by sulphur dioxide. Copolymerization of tung oil and linseed oil is therefore unlikely at temperatures below 250° C.

Copolymerization of oleic and elaidic esters with olefins derived from linoleic acid esters does not occur at 300° C; this makes it probable that mono‐unsaturated acids, when present in drying oil glycerides, do not participate in the polymerization.
Empêchement stérique dans la réaction des amines sur les quinones halogénées
Authors: Buu‐Hoï Ng. Ph. , Royer René , Hubert‐Habart Michel
Published: September 2010

Il est montré que la réaction entre les amines et les quinones halogénées telles que la 2,3‐dichloro‐l,4‐naphtoquinone et la chloranile est très sensible à l'empêchement stérique: plusieurs amines aromatiques encombrées en position ortho n'ont pas réagi dans les conditions expérimentales habituelles avec ces deux quinones.
The relation between emission and absorption spectra of molecular compounds of sym. Trinitrobenzene
Authors: Bier A. , Ketelaar J. A. A.
Published: September 2010

There exists a mirror‐image relation between the emission and the absorption spectra of the molecular compounds of sym, trinitrobenzene and some aromatic hydrocarbons.
The synthesis of thiazole‐2‐ and of thiazole‐5‐ carboxylic acid via a halogen‐metal exchange reaction)
Authors: Beyerman H. C. , Berben P. H. , Bontekoe J. S.
Published: September 2010

Two syntheses of the hitherto unknown 5‐bromothiazole are described. 2‐Bromothiazole and 5‐bromothiazole could be converted via the corresponding thiazolyllithium compounds into thiazole‐2‐ and thiazole‐5‐carboxylic acid respectively. This constitutes a new convenient synthesis of these acids, which up to now were rather difficultly accessible.
A two‐circle optical goniometer, specially adapted to measuring small crystals of organic compounds
Authors: Perdok W. G. , Terpstra P.
Published: September 2010

After a historical review of the development of goniometers for crystal measurements, a description is given of an improved, modernized construction.

It is emphasized that the instrument in its present form can be used for routine measurements without difficulty by any chemist with a minimum of crystallographic knowledge.
Aconic acid and related compounds: I. Discussion of the structure of aconic acid
Authors: Rekker R. F. , Brombacher P. J. , Hamann H. , Nauta W. Th.
Published: September 2010

To aconic acid, first described in literature by Kekulé, the structure of a β,γ‐butenolide was given by Fittig and Beer. In 1947 Campbell and Hunt put forward arguments for an α,β‐butenolide structure. These arguments were based on a new synthesis of the acid and a comparison of the U.V. absorption spectrum of aconic acid with those of mesaconic acid and itaconic acid. Close inspection of the properties of aconic acid shows however that Campbell and Hunt's synthesis of aconic acid is not proving for its structure.

Moreover these authors drew their spectral conclusions only from curveshapes, so we found it necessary to repeat the U.V. measurements at lower wave lengths. The rightness of the structure proposed by Campbell and Hunt could be proved.
On the ozonization and the ozonolysis of naphthalene, 2,3‐dimethylnaphthalene, and 1,4‐dimethylnaphthalene in connection with the reactivity of the ring system
Authors: Kampschmidt L. W. F. , Wibaut J. P.
Published: September 2010

From a kinetic investigation of the action of ozone on naphthalene and 2,3‐dimethylnaphthalene it appears that in both cases two molecules of ozone are rapidly taken up; the diozonide formed continues to react very slowly with ozone.

From the compounds formed upon ozonolysis of 2,3‐dimethylnaphthalene it follows that upon the action of ozone on 2,3‐dimethylnaphthalene two isomeric diozonides are formed; in one diozonide (main product) the O3 groups are bound in the methylated six‐membered ring, the other diozonide (by‐product) contains the O3 groups in the non‐methylated six‐membered ring.

On the strength of theoretical considerations and kinetic investigations of the ozonization reaction, a reaction mechanism is framed according to which the first molecule of ozone adds on to an α‐β bond of the ring system. From the reaction mechanism framed it is inferred what aliphatic and aromatic decomposition products may be formed in the ozonolysis of naphthalene and of 2,3‐dimethylnaphthalene. The decomposition products to be expected have all been found and identified. From the aromatic and aliphatic decomposition products formed in the ozonolysis of 1,4‐dimethylnaphthalene it follows that also upon the action of ozone on this naphthalene homologue a molecule of ozone primarily adds on to an α‐β bond.
Investigation into the type of particles occurring in concentrated solutions of 2‐1 electrolytes, in connection with the hydration of the ions
Authors: van Ruyven B. H.
Published: September 2010

This investigation is carried out on the basis developed for the 1‐1 electrolytes1).

With the aid of Raoult's law and the theory of Arrhenius the procedure for the calculation of the degrees of ionization is described when the three free ions together bind a H2O particles. The relation thus found is adapted for the elaboration of Tammann's data at 100°.

With the aid of the sulphates of positive ions the hydrations of which have been found for the 1‐1 electrolytes, the hydration of the SO4″ ion is calculated, upon which with H2SO4 solutions the hydration of the H* ion is found. This is verified with the aid of the acid sulphates having the positive ions already mentioned.

The equilibrium between the hydrated ions and the ion triplets is found to be determined by αpa2. Nω/(1‐αpa) = K*, where * indicates that for the constant K, a has been taken into account.

The hydrations of a number of bivalent negative ions are calculated. The hydration of the H* ion is dealt with more in detail.
Syntheses of polychloro compounds with aluminium chloride. XIV: The condensation of chloral with 1,2‐dichloroethene
Authors: Prins H. J. , Haring H. G.
Published: September 2010

This paper describes the compounds obtained by the condensation of chloral with 1,2‐dichloroethene (1,1,3,4,4‐pentachlorobutanone‐2; 1,2,4,4‐tetrachlorobuten‐1‐one‐3; 1,4,4,4‐tetrachlorobuten‐1‐one‐3; α,β,γ,γ‐tetrachloro‐n‐butyryl chloride), some derivatives, and the various reactions used to establish their structure.

Decomposition (by the action of aluminium chloride) of 1,1,1,3,4,4‐hexachloro‐2‐methoxybutane, obtained by the condensation of α,β,β,β‐tetrachloroethyl methyl ether with 1,2‐dichloroethene, yielded the same compounds, but in other proportions. An indication of the presence of these compounds was obtained by Raman analysis.

The mechanism of these reactions is briefly discussed.
Note sur la préparation des tétralkyl‐thiurames
Authors: Rothstein R. , Binovic K.
Published: September 2010

L'oxydation des dithiocarbamates par le ferricyanure de potassium, permet d'obtenir aisément les disulfures des tétralkyl‐thiurames avec d'excellents rendements.
α‐Substituted methylsulphonylacetonitriles: (Properties of the sulphonyl group XLII)
Authors: Dijkstra R. , Backer H. J.
Published: September 2010

A description is given of the preparation of substituted methylsulphonylacetonitriles CH3SO2CHXCN, X being CH3SO2, CO2C2H5, C6H5SO2, CH3SO or CN.
On the thermodynamics of micellar solutions
Authors: Stigter D.
Published: September 2010

An equation is derived for the association equilibrium in micellar solutions. The activity corrections are discussed on a general basis and evaluated, in the appendices, for the case of spherical micelles surrounded by a diffuse electrical double layer.
Δ5‐steroids and provitamins D with branched side chains, III. Preparation and reduction of some Δ5‐steroid‐ω‐amides
Authors: Louw D. F. , Strating J. , Backer H. J.
Published: September 2010

This paper deals with the dimethyl and diethyl amides of Δ5‐cholenic acid and Δ5‐bisnorcholenic acid. These amides could be converted into the corresponding unsaturated tertiary amines by reduction with LiAlH4.
Dipole moments and structures of dihalogenocyclohexanes
Authors: Kwestroo W. , Meijer F. A. , Havinga E.
Published: September 2010

Fifteen dihalogenocyclohexanes were synthesized, and their structure was investigated by means of dipole moment measurements. The measurements were carried out in solutions in benzene as well as in carbon tetrachloride at 30°. The results show that it is almost exclusively the chair conformations which coexist in the equilibrium, the flexible form not being present in any perceptible amount.

The trans‐1,4‐dihalogenocyclohexanes, where the results confirmed the assumption of μ = 0, form the simplest case. Since most conformations of the flexible form (with the exception of the so‐called stretched form) would show an appreciable moment, it seems improbable that they should be present to any important degree.

For the cis‐1,4‐, the cis‐1,2‐ and the 1,1‐dihalogenides exactly the same values of the dipole moments were found in the two solvents used. Since for these compounds the two chair conformations are either identical or mirror images, the constancy of the dipole moment in different solvents again supports the view expressed above. The presence of variable amounts of the flexible form in the equilibrium would result in a change of the value of the mean dipole moment upon varying the medium.

For the three trans‐1,2 compounds investigated, the dipole moments found proved to be dependent on the solvent used, the values being considerably lower in carbon tetrachloride than in benzene solutions. Significantly enough, it is precisely in these cases that the two possible chair conformations have widely different moments, the values for the la2a conformation being very low and the values for the le2e structures being around 3 D. Here the reality of an equilibrium between the two chair conformations thus becomes evident.

The values obtained for the dihalogenocyclohexanes could also be understood quantitatively on the basis of the assumption of the predominance of the chair conformations in the equilibrium. In order to calculate the moments by vector addition of partial moments (i.e. the values for cyclohexyl monohalogenides), corrections have to be applied, which are slightly different from those suitable for the aliphatic polyhalogenides.

Finally a short discussion is given on the problem of choosing a method of calculating “dipole moments” from data obtained with solutions, which is to combine simplicity with applicability to the study of molecular structure. A comparison of the Halverstadt‐Kumler method and that of Böttcher‐Scholte is made in the case of 1,1‐dichlorocyclohexane.
The structure of selenium tetrachloride in the solid and of tellurium tetrachloride in the liquid and the solid state
Authors: Gerding H. , Houtgraaf H.
Published: September 2010

Raman spectra were obtained for SeCl4 in the solid and for TeCl4 in the solid and the liquid state. Polarization measurements were performed for the stronger Raman lines of liquid TeCl4. The four stronger Raman lines of SeCl4 are very close in frequency to those of pyramidal AsCl3; there is also a close analogy between the frequencies of the stronger Raman lines of TeCl4 (both in the solid and in the liquid state) and those of antimony trichloride. These findings favour the assumption that solid SeCl4 and TeCl4 have to be written as SeCl3+Cl− and TeCl2+Cl− respectively, SeCl3+ being isosteric with AsCl3 and TeCl2+ with SbCl3. Force constant and frequency calculations have been effected for the hypothetical SeCl3+ and TeCl3+ ions. The results support the above assumption.
The steady‐state temperature difference in the Hill‐Baldes technique
Authors: Iyengar B. R. Y.
Published: September 2010

The molal steady‐state temperature differences δ for a number of solvents have been determined by the Hill‐Baldes technique, using a precision thermistor bridge. The values of δ obtained in the present investigation as well as those available in the literature have been explained on the basis of the theory of evaporation of droplets after introducing a thermal efficiency factor, which is characteristic of the experimental method employed. The application of this technique for the determination of molecular weights in solution is also discussed.
The polarographic reduction of conjugated hydrocarbons: V. The mechanism of the reduction of various alternant and non‐alternant hydrocarbons with aromatic and olefinic double bonds
Authors: Hoijtink G. J.
Published: September 2010

The current‐voltage curves of various members of the series: 1‐phenyl‐n‐biphenylene polyenes, 1‐phenyl‐n‐(2,3‐benzo‐)biphenylene polyenes, 1‐n‐dibiphenylene polyenes, phenylethenes, p‐tolylethenes, o‐tolylethenes, and phenylbutadienes were measured either in 75% or 96% dioxane‐water or in both. From the results of these investigations and from the revised data of the 1‐n‐diphenyl‐polyenes it appeared that the lower members of the series of polyenes are reduced according to the mechanism inferred in paper IV. The reduction of the higher members in all probability proceeds according to the mechanism: R + e → R′ + e → R″ + H* → RH′ + H* → RH2. The various factors governing this change of the reduction mechanism are discussed.
Ultraviolet absorption spectra and configuration assigned to various substituted 9,10‐dihydroanthracenes
Authors: la Lau C.
Published: September 2010

The reaction of 2‐cyano‐2‐propyl radicals with several anthracenes leads to the formation of a series of interesting 9,10‐substituted 9,10‐dihydro‐anthracenes, as shown by Engelsma, Farenhorst and Kooyman1); the investigated compounds may exist in pairs of cis‐ and trans‐isomers.

The present paper describes the spectrophotometric study of these compounds, which was aimed at providing a maximum of independent evidence for the structures assigned to the various derivatives.

From the recorded ultraviolet absorption spectra the following conclusions have been drawn:

) purity: the parent anthracenes are absent.

) type of ring system: the investigated compounds most probably contain two “isolated” benzene rings per molecule; assuming the preservation of the original carbon‐ring system it is readily shown that the investigated compounds are 9,10‐dihydroanthracenes.

) cis/trans assignment: evidence is given for the cis or trans configuration respectively assigned to the compounds, the conclusions agree with those arrived at previously1) on the basis of stereo‐kinetical considerations.
The mutarotation and ionization of d‐glucose in alkaline solution
Authors: Los J. M. , Simpson L. B.
Published: September 2010

The mutarotation of d‐glucose has been studied at 0°, 15° and 25° C in unbuffered, weakly alkaline solutions by recording the change of pH with time. The dependence of the specific mutarotation velocity on the glucose concentration was extensively measured.

Considering water, glucosate ions and hydroxyl ions as the only catalytically active agents, it was found that the catalytic constant of hydroxyl ions, kOH, is strongly dependent on the glucose concentration. This is the principal reason for the large discrepancy of values for kOH reported in the literature. The suggestion is made that this effect is caused by the omission of third‐order terms in the catalytic rate equation, corresponding to a concerted mechanism for the catalysis.

The ionization constants of α and β d‐glucose, Kiα and Kiβ respectively, have been measured for the first time. The β form is the stronger acid, causing the pH to decrease during mutarotation whenever the equilibrium is approached from the α side. Polarimetric measurements of the catalytic constant should be corrected for the change in pH.

Equations are given for kOH, Kiα and Kiβ as functions of the temperature.
A new apparatus for automatic coloration and extraction of the filter paper strips in electrophoresis on filter paper
Authors: Oosterhuis H. K. , Prins G. , Verleur H.
Published: September 2010

An apparatus is described which permits of efficient and simultaneous extraction of a large number of paper strips, as in use in paper electrophoresis. The fully automatic procedure reduces the amount of work required to a minimum.
Steric effects in the electronic spectra of substituted benzophenones. I: Symmetrically substituted methyl‐benzophenones
Authors: Rekker R. F. , Nauta W. Th.
Published: September 2010

The ultraviolet absorption spectra of benzophenones show well‐defined steric effects arising from ortho‐substitutions.

In this paper the experimental data are given for a series of 12 methylsubstituted ketones, including benzophenone.

From these data the oscillator strengths f were calculated for the C‐bands; mutual comparison of these f‐values gives and idea of the magnitude of the steric effects caused by ortho‐substituted methyl groups.
The thermochemistry of some redistribution reactions
Authors: Skinner H. A.
Published: September 2010

A “redistribution reaction” is defined. The heat of redistribution (ΔHr) is a direct measure of the departure of bond‐energy term values from constancy. ΔHr values are given for examples chosen from hydrocarbon chemistry, and discussed in terms of conjugation and hyperconjugation effects. Other examples from a wider field (including some redistribution reactions of alkyl halides, cyanogen, mercury alkyls, dimethylaminochloroborines) are used to illustrate the influence of polar groups, ionicity, and back‐coordination on bond‐energy variability.
Dérivés azotés du 2‐benzylfluorène et du 2‐(4′‐méthylbenzyl)fluorène
Authors: Buu‐Hoï Ng. Ph. , Royer René , Bisagni Emile
Published: September 2010

Dans ce travail, on étudie l'arylalkylation du fluorène par les chlorures de benzyle et de p‐méthylbenzyle; en raison du pouvoir cancérogène bien connu du 2‐aminofluorène, la Synthèse de plusieurs dérivés azotés du 2‐benzylfluorène et du 2‐ (4′‐méthylbenzyl) fluorène a été réalisée en vue de leur examen biologique comme substances cancérogènes possibles.
Adsorption and the deposition of carbon on cotton from solutions of sodium dodecyl sulfate
Authors: Vold Robert D. , Phansalkar Achyut K.
Published: September 2010

The deposition of carbon on cotton from solutions of sodium dodecyl sulfate of varying concentration was determined, together with the adsorption isotherms of NaDS on both cotton and carbon, and the aggregate size of the carbon in the suspensions.

An optimum concentration for protection against deposition of carbon was found far below the critical micelle concentration, and not correlating with either the presumed values of the zeta‐potential nor the extent of surface coverage by adsorbed detergent. Various explanations were considered and rejected for accounting for the inflection in the adsorption isotherm of NaDS on carbon at the c.m.c., and the subsequent occurrence of a maximum in the isotherm.
Contribution to the knowledge of metanethole IV
Authors: Zanden J. M. V. D. , de Vries G.
Published: September 2010

The structure of some of the compounds mentioned in our investigation of metanethole was still under discussion.

It has been found that metanethole has the structure V. When 1‐p‐methoxyphenyl‐2‐methyl‐3‐ethyl‐6‐methoxyindene‐1, formula I, is brominated 2), the product IV is obtained. To the metanethole oxidation product, m.p. 115‐116° 3), formula X 4)5) applies. With hydrazine hydrate it gives XI. Afterwards we also found this substance mentioned in work by A. Müller 5A).

The following substances not mentioned in the literature have now been synthesized by us: β‐p‐methoxyphenyl‐β‐m‐methoxyphenylcinnamic acid, m.p. 154‐155°, formula VII, β‐p‐methoxyphenyl‐β‐m‐methoxyphenyl‐β‐hydroxypropionic acid, m.p. 120° (with dec), formula VIII.
The action of ethyl diazoacetate on arylalkyl and dialkyl ethers: (Preliminary communication)
Authors: de Graaff G. B. R. , van Dijck‐Rothuis S. J. H. , van de Kolk G.
Published: September 2010

The results of a preliminary investigation on the action of ethyl diazoacetate on 1‐butoxybutane, 1‐methoxyheptane, and a series of arylalkyl ethers are described.

In every case but one, in addition to other processes, a remarkable reaction was observed, yielding the alkoxy or aryloxy derivatives of ethyl acetate.

Ethyl phenoxyacetate was formed by the action of the reagent on methoxy‐, ethoxy‐, propoxy‐ as well as isopropoxybenzene; 1,2‐, 1,3‐, and 1,4‐dimethoxybenzene gave ethyl 2‐, 3‐, and 4‐methoxyphenoxyacetate respectively.

1‐Methoxynaphthalene yielded ethyl 1‐naphthoxyacetate, but 2‐methoxynaphthalene was not converted into 2‐naphthoxyacetate, ethyl 1‐(2‐methoxynaphthyl) acetate being the chief reaction product.

The mixture formed during the action of diazoacetic ester on 1‐methoxyheptane contained the ethyl esters of both heptoxy‐ and methoxyacetic acid.

We have started a more extensive investigation on the reaction of ethyl diazoacetate and 1‐butoxybutane. In this case the fate of the alkyl radical expelled during the formation of the alkoxyacetic ester was revealed, since we isolated a considerable amount of butene‐1.
A new synthesis of 2,4,5‐trichlorophenoxyacetic acid (2,4,5‐T)
Authors: Huisman H. O. , Smit A.
Published: September 2010

A new synthesis of 2,4,5‐trichlorophenoxyacetic add (2,4,5‐T) is described.

A mixture of the insecticidally inactive α‐ and β‐isomers of hexachlorocyclohexane, obtained as a by‐product in the manufacture of the γ‐isomer is converted into 1,2,4‐trichlorobenzene. After converting the 1,2,4‐trichlorobenzene into 2,5‐dichlorophenol, the latter is reacted with monochloroacetic add to 2,5‐dichlorophenoxyacetic add and chlorinated into 2,4,5‐T. The overall yield of 2,4,5‐T calculated on H.C.H. is ca. 40‐50%.
On the reactivity of polynuclear aromatic amines
Authors: Sixma F. L. J.
Published: September 2010

The reaction velocities of a number of aminonaphthalenes, ‐anthracenes, and ‐phenanthrenes with 2,4‐dinitrochlorobenzene in ethanol were measured. It is shown that the logarithm of the reaction constants is inversely proportional to the localization energy or to the charge density at the extra‐cyclic atom as calculated for the hydrocarbon analogues of the amines.
The calculation of some equilibria with alkenes
Authors: van Zijll Langhout W. C. , Korvezee A. E. , Waterman H. I.
Published: September 2010

The thermodynamic quantities of the terms of homologous series in general vary linearly with the number of carbon atoms. Making use of the linear trend of the free enthalpy and, where possible, allowing for a deviation in the case of the lowest terms (initial term effect), we have calculated the composition of a number of equilibrium mixtures in homologous series at temperatures of 300°K−1000°K, and reproduced these compositions in graphs. Deviations from the ideal gas laws and the possible occurrence of liquid have been left out of consideration. As the summation over a limited number of terms leads to relatively simple equations, more complicated equilibria can also be dealt with. Here the following equilibrium mixtures have been calculated:

) n‐l‐alkenes

) n‐l‐alkenes and n‐alkylcyclohexanes, and

) n‐l‐alkenes, n‐alkane‐thiols, and hydrogen sulphide.
The solubility of some normal saturated fatty acids in an aqueous sodium glycocholate solution
Authors: Verkade P. E. , Meerburg W.
Published: September 2010

This paper contains data on the solubility of a number of normal saturated fatty acids (C8‐C15) in a 2.32% aqueous sodium glycocholate solution at 25.0° and 37.0°. The data are discussed with reference to alternation phenomena in homologous series and to the transport of fatty acids through the intestinal wall.
The chemistry of acetylenic ethers XI: Preparation of acetylenic ethers from aldehydes
Authors: Arens J. F.
Published: September 2010

A method for the preparation of acetylenic ethers starting from aldehydes I is described. The aldehydes are transformed into α‐chloroethers II and these are halogenated to α,β‐dihalogeno‐ethers III. By means of diethylaniline a molecule of hydrogen halide is eliminated, yielding a β‐halogeno‐α,β‐unsaturated ether IV. From this a second molecule of hydrogen halide can be eliminated by heating with potassium hydroxide, resulting in the formation of an acetylenic ether V.
Peroxidative detoxification of diphtheria toxin studied by using I131
Authors: Agner Kjell
Published: September 2010

From 50 to 60 different substances ‐ mainly aromatic amines and phenol derivatives ‐ have been tested as to the possibilities to use them as co‐factors in peroxidative detoxification experiments on diphtheria toxin.

Results obtained with oxidized I−, admixed with I131−, indicate that the oxidized co‐factors combine with special groups in the toxin molecule.
The metabolism of S35‐ labelled antithyroids in the thyroid gland and other organs of cockerels
Authors: van Erkelens P. C.
Published: September 2010

We studied the metabolism of (S35‐labelled)4‐methylthiouracil and 4‐carboxylthiouracil in the thyroid gland and other organs of cockerels.

The main result is that the drugs are nor incorporated in the nucleic acids or in the protein fractions, but that they are oxidized to sulphate.

Further, the percentages of the nucleic acids in the thyroid gland and pituitary gland were nor altered by the drugs.
Optical measurements with ultraviolet and visible light applied to clinical problems
Authors: Wootton I. D. P.
Published: September 2010

The use of the quartz spectrophotometer in the clinical laboratory is described, with typical applications to common analyses. The problems involved in setting up a flame photometric estimation are discussed and a suggestion made about future developments.
The polarographic estimation of ketosteroids
Authors: Morris C. J. O. R.
Published: September 2010

The technique of estimation of ketosteroids by polarography of their Girard hydrazones is discussed with special reference to the determination of 17 and δ 4:3 ketosteroids.

The application of the polarographic method to estimation of urinary 17 ketosteroids is described together with a new rapid procedure employing hydrolysis of the steroid complexes with p‐toluene sulphonic acid.

The use of polarography in the determination of individual corticosteroids in human blood is demonstrated and experimental procedures and results described.
Potentiometric determination of chlorides in biological fluids: Microgram analysis
Authors: Sanz Manuel C. , Brechbühler Tony
Published: September 2010

A simple electrode system for the determination of a few gammas of chloride in the presence of proteins is proposed. The high‐potential jump at the equivalence point permits the use of a normal valve potentiometer. A. new ultramicro burette is described.
Die photometrische Percuprimetrie von normalen und pathologischen Serumproteinen
Authors: Beck G. , Spengler G.
Published: September 2010

In alkalischer Lösung werden die Proteine von Kaliumcupri‐3‐perjodat oder Tellurat oxydativ abgebaut, indem die Peptidbindungen gesprengt werden, wobei Formiat und Säureamide gebildet werden. Da die verschiedenen Peptidbindungen sich in den Reduktionspotentialen unterscheiden, so reagieren sie verschieden schnell mit CuIII. Wenn man die Oxydation der Proteine in Teiltitrationen auflöst und den Vorgang mit dem Photometer zeitlich jedesmal miszt, so erhält man durch Verbindung der Punkte eine charakteristische Glockenkurve. Bei den Percuprigrammen der Globuline von Carcinomen fanden wir einheitliche Abweichungen vom normalen Kurvenbild sogar bei Präcancerosen. Auch bei Röntgenbestrahlung treten Veränderungen ein, und bei Tuberkulosen kann man andere Veränderungen feststellen.
Über die Möglichkeit der Trennung von Steroiden mittels Papier‐Elektrophorese und Gegenstromverteilung
Authors: Schroeder W. , Voigt K. D.
Published: September 2010

Der Fortschritt, der für die Trennung von Steroidgemischen mit Hilfe der Papier‐ und Säulenchromatographie erzielt wurde, ist allgemein bekannt. Die relative Umständlichkeit dieser Verfahren liess uns nach anderen Trennmöglichkeiten suchen. Dabei bot sich die Papierelektrophorese an. Nach Veresterung mit Bernsteinsäurenanhydrid und Darstellung des Natriumsalzes ist eine Trennung sowohl von kristallinen Steroiden als auch von im Harn erscheinenden Steroidabbauprodukten möglich. Da es sich bei den dabei erhaltenen Fraktionen zum Teil noch um Steroidgemische handelt, unterwarfen wir sie der Gegenstromverteilung. Die Auswertung erfolgt UV‐spektrophotometrisch. Die dabei erhaltenen Ergebnisse werden diskutiert.
La Determination De L'Activite Cholinestérasique Du Sang En Vue De La Detection Des Intoxications Par Les Insecticides organo‐phosphores
Authors: Fournel Julien
Published: September 2010

La mesure du pouvoir cholinestérasique du sang chez les personnes en contact avec les insecticides organo‐phosphorés est un moyen de déceler toute intoxication provoquée par l'absorption accidentelle de ces substances avant l'apparition de symptǒmes subjectifs. L'examen systématique du personnel d'un laboratoire de recherches phytopharmaceutiques a permis de mettre en évidence dans quelques rares cas des valeurs cholinestérasiques anormales traduisant une légère atteinte par ces insecticides, ce qui a permis de prendre en temps utile des mesures d'hygiène industrielle convenables.
Fermentuntersuchungen in der Skeletmuskulatur bei Arteriosklerose und Endangites obliterans
Authors: Schmidt C. G. , Schlief H. , Hillenbrand H. J.
Published: September 2010

In Amputationspräparaten von Patienten mit fortgeschrittener Arteriosklerose und Endangitis obliterans wurde in unmittelbarer Nachbarschaft zu nekrotischen Anteilen der Skeletmuskulatur die Aktivität der Succino‐dehydrogenase, des Succinoxydase‐ und Cytochromoxydase‐Systems, der Hexokinase, ATP‐ase und der sauren und alkalischen Phosphomonoesterasen sowie der Gehalt an Glykogen bestimmt. Im Gegensatz zu den schweren klinischen Erscheinungen mit zum Teil ausgedehnten distalen Nekrosen blieb die Aktivität der Fermente in unmittelbarer Nachbarschaft der Nekrosen unverändert. In den Randzonen von Nekrosen ist dagegen neben starker Verminderung des Glykogenbestandes die Aktivität dieser Fermente herabgesetzt, die der alkalischen Phosphormonoesterasen gesteigert. Trotz der Tendenz zur Generalisierung weisen die Ergebnisse daraufhin, dass die Folgen der Gefässprozesse durch die Ausbildung von Kollateralen auf eng begrenzte Bezirke beschränkt sind.
The importance of the iodoacetate index in cancer
Authors: Papadopoulou Daphne
Published: September 2010

The Iodoacetate Index may be useful in assisting the clinical diagnosis of cancer (primary affection, relapse, metastasis) and in controlling the treatment.
Studies in contact potentials : I. Determination of the surface potential of some films on tungsten and mercury by the condenser method and a new form of the thermionic method
Authors: Mignolet J. C. P.
Published: September 2010

The author first decribes a new form of the thermionic method based on the shift of resistance characteristics. The resistance of the diode is measured with an A.C. bridge, care being taken to keep the emitter at constant temperature, even in the presence of gas. Cells suitable for tungsten deposits are described. The WH, WXe, and HgXe films have been studied by both the thermionic and the condenser method, and excellent agreement has been found for the surface potentials. For the WH and WN films, the surface potentials obtained are in grave disagreement with those of Bosworth 4) and of Bosworth and Rideal 5, 6) on tungsten wires. It is shown that Bosworth's value cannot refer to a WH film. The work function of a deposit stabilized between 293 and 428° K is close to that of a polycrystalline wire. Sintering increases the work function.
Studies in contact potentials,,: II. The competitive adsorption of hydrogen atoms and molecules on tungsten
Authors: Mignolet J. C. P.
Published: September 2010

Surface potential measurements show the adsorption of hydrogen on tungsten to be complex. Besides the negative effect due to the familiar atomic film, a positive effect is observed.

Experimental evidence reveals two important points, viz, (i) the positive effect is due to a molecular adsorption, and (ii) at the approach of saturation, the latter is able to compete with the atomic adsorption.

The properties of the mixed adsorption of atoms and molecules on a surface are examined theoretically. Three main conclusions are reached. The competition between the atomic and molecular adsorptions may give rise to a special mode of adsorption, consisting in the replacement of atoms by molecules and taking place near saturation on a surface with practically no vacant sites. Through substitution, a molecular adsorption may compete with an atomic adsorption with double the differential heat of adsorption. The saturated mixed film is normally non‐stoichiometric. The model provides a satisfactory explanation of some peculiarities of the positive effect.

The high heat of the molecular adsorption (up to 8 kcal/mole) is to be attributed essentially to the charge transfer forces, the contribution of which is much greater than that of the dispersion forces.

Using the above ideas, it is shown that the evidence regarding the catalytic hydrogen exchange at low temperature is in favour of the Rideal mechanism.

Substitutional adsorption is an activated process. It may account for a part of certain effects frequently attributed to dissolution.
The reaction of diazomethane with benzoquinones
Authors: Spruit C. J. P.
Published: September 2010

The reaction of diazomethane with p‐benzoquinone and several of its derivatives in the presence of an oxidizing agent leads to the formation of derivatives of isoindazole‐4,7‐quinone.
A note on the mercuration of some types of furan derivatives
Authors: Verkade P. E. , Morel Th. , Gerritsen H. G.
Published: September 2010

Suitable furan derivatives can be readily mercurated in β‐position. However, the introduction of a chloromercuri group in β‐position proceeds much more slowly than that in α‐position. Some applications of this difference in mercuration rate are discussed.
Intramolecular energy transfer in bimolecular reactions
Authors: Pritchard H. O.
Published: September 2010

The possible contribution of internal degrees of freedom to the activation of simple bimolecular reactions is discussed in terms of a classical model; it is suggested that existing experimental data on the reactions of halogen atoms with isobutane and of sodium atoms with the alkyl halides may prove to be examples of such behaviour.
Excelsin, edestin, and tobacco seed globulin crystals. Preparation, density, and X‐ray measurements
Authors: Drenth J. , Wiebenga E. H.
Published: September 2010

The vegetable proteins excelsin, edestin, and tobacco seed globulin were obtained from seeds, and the purity of the preparations was tested. Crystals were grown from solutions by dialysis against water. Their optical properties were examined and their densities were measured at different water contents. Single‐crystal X‐ray photographs were obtained from excelsin equilibrated with air of various relative humidities, and from tobacco seed globulin and edestin in both the dry and the wet state. The photographs were rather poor, except for excelsin, which, in a certain range of water content, shows reflections corresponding to spacings down to 4 Å. Its Laue symmetry is R 3m. A more detailed X‐ray investigation of excelsin, involving the introduction of heavy atoms into the structure, is in progress.

The structures of the three proteins may be represented by approximate close packings of spheres. The molecular weights as calculated from the unit cell dimensions and densities of the dry crystals are 303,000 (± 10,000), 360,000 (± 20,000) and 350,000 (± 20,000) for excelsin, edestin, and tobacco seed globulin respectively.

The relationship between the specific volume of excelsin and its water content is discussed.
The oxidation of phenols with copper‐amine catalysts and its relation to the mode of action of tyrosinase: I. The catalytic oxidation of monohydric phenols to orthoquinone derivatives
Authors: Brackman W. , Havinga E.
Published: September 2010

In an attempt to imitate the action of the enzyme tyrosinase by means of simple homogeneous catalytic systems we have found some rapid reactions which convert monohydric phenols directly into amine‐substituted orthoquinone derivatives. These reactions proceed rapidly at room temperature with molecular oxygen as an oxidant and copper‐amine complexes as catalysts. The reactions may be applied to a variety of phenols and of primary or secondary amines.

It is argued that the monohydric phenols are primarily converted into the corresponding orthoquinones. Paraquinones are not formed or formed in traces only. The quinones are subject to rapid spontaneous addition reactions with the primary or secondary amines, thus giving rise to substituted catechols, which are oxidized to the corresponding orthoquinones.

In the instances studied, the orthoquinone derivatives were formed in high yield. As they are converted easily in the corresponding phenazines and hydroxyquinones, the latter compounds may thus be synthesized in a convenient way from monohydric phenols and naphthols.

The present paper deals with the nature of the reaction products only. Kinetics and reaction mechanism are discussed in following papers. The reactions studied in some detail are: The conversion of phenol into dimorpholino‐orthobenzoquinone (yield 64%) and of α‐ and β‐naphthol into 4‐morpholino‐1,2‐naphthaquinone (37 and 84%).

The effect of morpholino substituents on the redox potential of quinones has been measured.

The following new compounds are described in this paper: 4,5‐dimorpholino‐orthobenzoquinone, 2,3‐dimorpholinophenazine, 4‐morpholino‐1,2‐benzophenazine.
Syntheses, with the aid of (4‐pyridyl)‐magnesium chloride, of 4‐lithiopyridine and of 3‐lithioquinoline
Authors: Wibaut J. P. , Heeringa L. G.
Published: September 2010

4‐Chloropyridine can be converted for about 70% into a complex magnesium compound, which reacts in the manner of a Grignard compound with aldehydes or ketones, forming (4‐pyridyl)‐carbinols; with orthoformic ester, (4‐pyridyl)‐methanal‐acetal is formed.

The reaction of 4‐lithiopyridine with benzophenone and with ethyl benzoate respectively leads to the formation of (4‐pyridyl)‐diphenyl‐carbinol and to bis‐(4‐pyridyl)‐phenyl‐carbinol respectively. With aromatic nitriles, (4‐pyridyl)‐aryl ketones are formed.

The reactions of 4‐lithiopyridine with cyanopyridines or with pyridine‐carboxylic esters lead to the formation of bis‐pyridyl ketones, e.g., bis‐(4‐pyridyl) ketone.

Quinolyl ketones are obtained by starting from 3‐lithioquinoline.
Cerimetric determination of hypophosphite
Authors: Sastri M. N. , Kalidas Ch.
Published: September 2010

A rapid method for the cerimetric determination of hypophosphite has been worked out, using silver salt as a catalyst. An excess of standard ceric sulphate solution is added to a solution containing hypophosphite acidified with sulphuric acid, and subsequently 2 ml of a 5% solution of Ag2SO4 in conc. sulphuric acid. The mixture is kept at the temperature of a boiling water bath for 20 minutes, and the unreacted eerie sulphate is determined with ferrous ammonium sulphate, after the mixture has been cooled.
Chemical behaviour of 3‐aminopyridine and of 3,5‐diaminopyridine. Syntheses of (3‐pyridyl)‐pyrazolones
Authors: Zwart C. , Wibaut J. P.
Published: September 2010

Through conversion of 3‐nitraminopyridine, two x‐nitro‐3‐aminopyridines are obtained in a very small yield. By bromination of 3,5‐bis‐(acetylamino) pyridine, a small yield of a dibromo derivative is obtained.

From 3‐amino‐5‐bromopyridine the following compounds are prepared via the diazonium compound: 3‐bromo‐5‐fluoro‐pyridine, 3‐bromo‐5‐iodopyridine, 3‐bromo‐5‐cyanopyridine, and some azo dyestuffs.

From (3‐pyridyl)hydrazine and ethyl acetoacetate 1‐(3′‐pyridyl)‐3‐methyl‐pyrazolone‐5 is obtained; from 3‐amino‐5‐bromopyridine, a (bromopyridyl)‐methylpyrazolone is obtained in an analogous manner.
New musk odorants: The structure of tert.amylated p‐cymene. A new synthesis of polyalkylindans. I
Authors: Weber S. H. , Spoelstra D. B. , Polak Ernest H.
Published: September 2010

The reaction of p‐cymene with tert.amyl alcohol or methylbutenes in the presence of sulphuric acid or with tert.amyl alcohol or tert.amyl chloride in the presence of aluminium chloride according to the Friedel Crafts method, has been found to yield a polymethylindan mixture consisting of 41% of 1,1,2,3,3,5‐hexamethylindan (XXI), 23% of 3‐ethyl‐1,1,3,5‐tetramethylindan (XX), and 12% of 1,1,3,3,5‐pentamethylindan (III). In addition, 1,2,3,3,5‐pentamethylindan (II) and 1,1,2,3,5‐pentamethylindan (I) have been synthesized.

Introduction of an acetyl group into the aromatic nucleus of the first four indans results in indanyl methyl ketones having a musk odour, acetyl‐1,1,2,3,3,5‐hexamethylindan (XXVIII) being the most important of these.
Studies on vitamin D and related compounds IV: The pattern of the photochemical conversion of the provitamins D
Authors: Havinga E. , Koevoet A. L. , Verloop A.
Published: September 2010

Solutions of about equal amounts of 7‐dehydrocholesterol‐3‐C14 and (inactive) lumisterol3 were irradiated with ultra‐violet light (265‐280 mμ) for short periods of time, resulting in approximately 10% conversion of the provitamin. Similar experiments were performed with labelled ergosterol (obtained by growing yeast in a medium containing acetate‐1‐C14), admixed with inactive lumisterol2 and tachysterol2. Isolation of the compounds present in the irradiated solutions was effected by precipitating the pro‐vitamin D with digitonin and separating the remaining components according to their different rates of reaction with maleic anhydride (tachysterol > vitamin D> lumisterol). The specific radio‐activities of the products isolated gave clear‐cut evidence that lumisterol does not play any part as an intermediate in the main route of the reaction provitamin D → tachysterol nor in the conversion provitamin D → vitamin D. Besides, lumisterol seems to be formed at a relatively low rate under the conditions employed, which are comparable with those generally used in vitamin D synthesis. As to tachysterol, here conclusions were somewhat less definite because this compound has rather a high rate of photochemical formation and decomposition and is difficult to purify. The specific activity measurements, however, strongly supported the conclusion that also tachysterol is not a necessary intermediate in the vitamin D formation. Thus the results are contradictory to the traditional scheme provitamin D magnified image lumisterol magnified image tachysterol magnified image previtamin D ⇄ vitamin D, and are strongly in favour of a reaction pattern of the following type: magnified image
A new method for the preparation of aromatic ISO thiocyanates
Authors: van der Kerk G. J. M. , Pluygers C. W. , de Vries G.
Published: September 2010

A new method is given for the preparation of aromatic isothiocyanates from the corresponding dithiocarbamates. The latter compounds are converted into S‐(carboxymethyl) ‐dithiocarbamates, which spontaneously decompose at pH 7 in the presence of certain heavy metal ions to yield isothiocyanates. The reaction mechanism is discussed.
Synthesis of a potential oestrogen 1,3‐dimethyl‐7‐hydroxyphenanthrene‐2 carboxylic acid
Authors: van der Meer S. , Veldstra H.
Published: September 2010

With plant growth substances there exists a certain (spatial) equivalence, as to physiological activity, between tetrahydro α‐naphthoic acids and both β‐substituted α‐napthoic acids and 2,6‐disubstituted benzoic acids.

It was tried therefore whether in the highly active oestrogens of the bisdehydrodoisynolic acid type the tetrahydro β‐napthoic acid part could be replaced by a di‐ortho substituted β‐naphthoic acid structure, while retaining activity.

For this reason 1,3‐dimethyl‐7‐hydroxyphenanthrene‐2 carboxylic acid was synthesized. In the Allen‐Doisy test, however, only a slight indication of oestrogenic activity was found.
Some indan and tetralin derivatives as potential analgesics and antispasmodics
Authors: Akkerman A. M.
Published: September 2010

A number of indan and tetralin derivatives with structural features characteristic of highly active morphine substitutes were synthesized.

The compounds were tested for analgesic and antispasmodic activity. In none of the cases, however, these activities came up to the level required for practical application.
The preparation of ortho and para hydroxybenzyl alkyl ethers
Authors: de Jonge J. , Bibo B. H.
Published: September 2010

The preparation of some alkyl ethers of ortho and para hydroxybenzyl alcohol is described.
The electrodic behaviour of electro‐deposited manganese dioxide in solutions of different pH Part II
Authors: Issa I. M. , Khalafalla S. E. , Sadek E. A.
Published: September 2010

The potentials of MnO2, prepared by electro‐deposition on a platinum base and containing some lower oxide, vary with the pH of the solution. In acid solutions (pH 1‐5), ΔE/ΔpH amounts to 0.120 with an Eo′ = 1.38 volts at 25° C. From pH 7‐12, ΔE/ΔpH amounts to 0.060 with an Eo′ = 1.125 volts. In acid solutions the electrodes behave like MnO2/Mn+2, and in alkaline solutions like Mn(OH)3/Mn(OH)2 systems. The kinetics of the reaction in alkaline medium are discussed, and an equation expressing the variation of potential with time is developed.
A polarographic determination of glycyrrhizic acid in succus liquiritiae
Authors: Onrust H. , Jansen A. P. , Wöstmann B. S. J.
Published: September 2010

A description is given of a quantitative polarographic method for determining the glycyrrhizic acid content of succus liquiritiae.

The succus is dissolved in dioxane‐water and after hydrolysis with dilute add the hydrolysate is extracted with chloroform. An aliquot of this extract is evaporated to dryness and the residue is taken up in alcohol. Prom this solution a polarographic test solution is prepared.
Δ5‐Steroids and provitamins D with branched side‐chains, IV: The conversion of some Δ5‐steroids into provitamins D
Authors: Louw D. F. , Strating J. , Backer H. J.
Published: September 2010

The conversion of some new Δ5‐steroids1) into the corresponding provitamins D is described. The preparation of a provitamin D with a side‐chain ending in a tertiary amine function has been realized by reduction of the add amide with LiAlH4.

The irradiated products show only very slight anti‐rachitic properties.
Sur des dérivés de la 4‐rhodananiline d'intérêt pharmacologique
Authors: Buu‐Hoï N. P. , Loc T. B. , Xuong N. D.
Published: September 2010

Les propriétés chimiques de la 4‐rhodananiline ont été étudiées, et cette amine utilisée avec succès pour la synthèse de plusieurs composés possédant une activité antibactérienne importante contre divers microorganismes (bacilles tuberculeux, streptocoques, pneumocoques, méningocoques), et appartenant aux groupes des thiocarbanilides et des sulfanilamides.