bluuebunny/crossref_metadata_2025 huggingface dataset:
Oxydation de thiophènes en sulfones propriétés du groupe sulfonyle XXXIV
Authors: Melles J. L. , Backer H. J.
Published: September 2010

La difficulté d'obtenir des sulfones par oxydation de thiophènes a deux causes: la stabilité du groupement électronique dans L'anneau “aromatique” de thiophène et L'abaissement de cette stabilité par suite de L'oxydation du soufre. Ce mémoire étudie L'influence de substituants sur la possibilité de préparer des sulfones.
Synthetic anticoagulants. I. 1‐Alkoxy‐2,2‐bis‐(4‐hydroxy‐coumarinyl‐3) ethanes
Authors: Veldstr H. , Wiardi A. P. W. , Alberda G.
Published: September 2010

New synthetic anticoagulants were obtained in the series of 1‐alkoxy‐2,2‐bis‐(4‐hydroxy‐coumarinyl‐3)ethanes (III). In the rabbit the most active members of this group are as active as dicoumarol (I), while they equal ethyl biscoumacetate (II) with respect to resorption and rapid elimination. Clinical investigations are in progress.
Phosphatide acids and derivatives: I. Synthesis of phosphatidic acids derived from glycol, starting from monoacylglycols
Authors: van der Neut J. H. , Uhlenbroek J. H. , Verkade P. E.
Published: September 2010

In the presence of pyridine or quinoline monoacylglycols and diphenyl chlorophosphate react smoothly at room temperature, with the formation of acylglycolphosphoric acid diphenyl esters. Upon hydrogenolysis the latter substances yield the acylglycolphosphoric acid and cyclohexane.

Some properties of these new types of compounds are discussed.
Macrocyclic oxalactones
Authors: Beets M. G. J. , Meerburg W.
Published: September 2010

Three new macrocyclic oxalactones have been prepared. Their synthesis and properties are described, and a new technique for the preparation of ω‐bromo‐alkanols is introduced.
The activation of chymotrypsinogen
Authors: Mars P. H.
Published: September 2010

Kunitz and Northrop1) found that a small amount of non‐protein‐Nitropen (N.P.N) was formed during slow activation of chymotrypsinogen by trypsin. No conclusion was drawn whether or not the appearance of N.P.N. coincided with the formation of α‐chymotrypsin. Butler2) repeated their experiment, using higher concentrations of trypsin in order to speed up the activation. He concluded that no N.P.N. was formed during rapid activation. Jacobsen3) also employed rapid activation in his investigations, and he found that hydrolysis consisted of two steps: first, π‐chymotrypsin was formed and, secondly, δ‐chymotrypsin. The amount of N.P.N. released during conversion was ascribed to a side reaction.

In the present work the slow activation of chymotrypsinogen was investigated chromatographically. The chymotrypsinogen used was dialysed at pH 3.0, and was found to contain neither peptides nor amino‐acids. The products of slow activation were chromatographed, and several spots appeared. One was due to a peptide. This peptide contains arginine, since the spot gave a positive Sakaguchi reaction.

The peptide was isolated and analysed by paper chromatography, and was found to consist of: arginine, lysine, alanine, serine, glutamic acid, and phenylalanine. Faint spots were also found at the places of threonine, aspartic acid, glycine, and methionine.

On the other hand, in rapid activation the peptide spot appeared much later than the other spots. This agrees with Jacobsen's finding that the formation of δ‐chymotrypsin exceeds the formation of α‐chymotrypsin during rapid activation.

Desnuelle4) found no dinitrofluorobenzene‐reactive N‐terminal groups in chymotrypsinogen, but he did find two such groups in α‐chymotrypsin.

According to Neurath et al.5) leucine (or isoleucine) and tyrosine occupy C‐terminal positions in α‐chymotrypsin. This, in conjunction with the substrate specificity of trypsin and carboxypeptidase, led them to the conclusion that a peptide containing lysine or arginine is split off during the conversion of chymotrypsinogen. Our findings are in agreement with their hypothesis.

A detailed study will be published later.
Phosphatide acids and derivatives: III. The behaviour of glycerophosphatidic acids towards alkali
Authors: Uhlenbroek J. H. , Verkade P. E.
Published: September 2010

Boiling α‐glycerophosphatidic acids with alcoholic sodium hydroxide gives only glycerol‐α‐phosphoric acid, whereas from β‐glycerophosphatidic acids only glycerol‐β‐phosphatidic acid is formed. It is pointed out that esters of these phosphatidic acids behave quite differently.
A binary space model with volume, composition and temperature as variables
Authors: Zernike J.
Published: September 2010

Construction of a v‐t‐x space model; its v‐t and v‐x projections, and sections at constant volume. Critical comparison with such diagrams from the literature.
Complex ‐ chlorides II: Conductometric titration of PCl5 ‐ compounds
Authors: Groeneveld W. L. , Zuur A. P.
Published: September 2010

The existence of POCl3‐complexes of complex‐forming chlorides (e.g. SnCl4, TiCl4, SbCl5), combined with the precipitation method in POCl3for the preparation of PCl5‐compounds 1). strongly creates the impression that there might be an analogy between the H2O and the POCl3 systems. It is known that hydrates of complex‐forming chlorides are decomposed by e.g. CsCl

2CsCl + SnCl4 · nH2O → Cs2SnCl6 + n H2O

2 PCl5 + SnCl4 · n POCl3 → (PCl4)2SnCl6 + n POCl3

In order to get some information about the possibility of this process, the system POCl3‐PCl5‐complex‐forming chloride is investigated by conductometric titration.
Steric effects on mesomerism: XI, The ultra‐violet absorption spectrum of Tröger's base and the stereochemistry of aromatic amines
Authors: Wepster B. M.
Published: September 2010

A careful analysis of molecular models shows that in Tröger's base (I) the configuration of the two aniline systems can be described as skewpyramidal with an angle of twist of 45°. The ultra‐violet spectrum of this compound reveals that in this configuration the mesomeric interaction between the benzene ring and the amino group is by no means eliminated. The consequences of this are discussed with respect to the connection between spatial configuration and mesomerism in aromatic amines, and are placed on a semi‐quantitative basis by comparison of oscillator strengths.

The results obtained are utilized in a fairly detailed discussion of the stereochemistry of aromatic amines. Configurations with pyramidal nitrogen appear to be definitely more favourable from an energy point of view than configurations with planar nitrogen.
The calculation of the specific refraction of tri‐n‐alkylalkoxysilanes
Authors: Breederveld H. , Waterman H. I.
Published: September 2010

The specific refraction (r) of tetra‐n‐alkylsilanes and tetraalkoxysilanes can be calculated very accurately by adding the respective group refractions according to Smith1) 2) and dividing the obtained molar refraction (M) a) by the molecular weight. If this method is used to calculate the specific refraction of silanes containing groups of different types, deviations are said to occur. In agreement with this principle, which holds in general and can be explained on the ground of the English theory3), the present authors found that the specific refractions of tri‐n‐alkylalkoxysilanes are in general lower than the calculated values. This decrease of the specific refraction is caused by the fact that alkoxy groups have greater electron‐attracting properties than alkyl groups, which will be discussed.
On the reaction of phenylbutadiene with formaldehyde
Authors: Beets M. G. J. , Drukker E. A.
Published: September 2010

The reaction of trans‐1‐phenylbutadiene‐1.3 with aqueous formaldehyde solution in the presence of an acid catalyst has been studied. The main reaction product is shown to be trans‐4‐styryl‐m‐dioxane. The structure and properties of both this compound and its hydrogenation product are discussed.
The heats of adsorption of hydrogen on Ni‐SiO2 catalysts
Authors: Schuit G. C. A. , de Boer N. H.
Published: September 2010

The heats of adsorption of hydrogen on several Ni‐SiO2 catalysts were determined from the dependence of the amounts adsorbed on the pressure and the temperature. Three systems were investigated: a sample obtained by reduction of an imperfectly crystallized Ni‐montmorillonite, a coprecipitate and an impregnation catalyst. The three systems were only found to differ in the total amounts of hydrogen adsorbed. The following equation was found to apply for temperatures between 195° K and 673° K and pressures from 0.1 to 100 mm Hg.

\documentclass{article}\pagestyle{empty}\begin{document}$${\rm RT}\ln {\rm p}({\rm atm}) + {\rm T}\left\{ {\frac{{\mu _{\,{\rm T}}^ \circ - {\rm h}_{\, \circ }^ \circ }} {{\rm T}}} \right\} - 2{\rm RT}\ln \frac{{\Theta _{\rm H} }} {{1 - \Theta _{\rm H} }} = - 24.000 + 14.400\Theta _{\rm H} {\rm cal}\,{\rm mole}^{ - 1}$$\end{document}

In this equation μ°T‐° °/T is the “free energy function” of gaseous hydrogen and ΘH is the fractional coverage assuming total coverage at 195° K and 1 atm.

Heats of adsorption deduced from this equation were found to be 5 kcal/mole−1 lower than those reported for Ni‐films, but higher than others reported for nickel obtained by reduction. The possible causes of these differences are discussed.
The influence of the refractive index on the absorption of light by solutions
Authors: Schuyer J.
Published: September 2010

Starting from the theory of Onsager‐Böttcher a new formula is derived by which the influence of the refractive index on the molar extinction coefficient of a solution can be calculated.

As this formula is rather complicated, approximation formulae are given for certain types of solutions. These formulae prove to be in better agreement with experiments than the formula of Chako‐Kortüm.
The Raman and infrared absorption spectrum of selenophene
Authors: Gerding H. , Milazzo G. , Rossmark H. H. K.
Published: September 2010

The Raman frequencies of liquid selenophene are communicated here. The infrared absorption bands of liquid selenophene have been determined in the region 1600‐670 cm−1 mainly, using a Perkin Elmer instrument with a rock salt prism and by Dr. Lecomte in Paris for the lower frequency region (about 390‐600 cm−1), making use of a grating spectrometer. Quantitative depolarization ratios were determined for the not too weak Raman lines.

Selenophene has a non‐planar configuration with only one symmetry plane remaining (symmetry C15). A striking analogy exists between many features of the vibrational spectra of selenophene and thiophene.
2,2′‐Azoisobutane
Authors: Farenhorst E. , Kooyman E. C.
Published: September 2010

A synthesis of 2,2′‐azoisobutane is described. This new compound gives tertiary butyl radicals and nitrogen upon thermal decomposition.
Preparation of 4‐nitro‐2,6‐xylidine
Authors: Kloosterziel H.
Published: September 2010

4‐Nitro‐2,6‐xylidine (4‐nitro‐2,6‐dimethylaniline) has been obtained by the interaction of ammonia and 4‐nitro‐2,6‐xylenol (4‐nitro‐2,6‐dimethylphenol), an easily accessible compound.
The exchange of chromium between chromium (II) and chromium (III) ions
Authors: van der Straaten H. , Aten A. H. W.
Published: September 2010

A rapid exchange of radioactive chromium has been observed between Cr+++ and Cr++ ions.
Three‐phase curve of ammonium bicarbonate
Authors: Zernike J. , Ahmed Qazi Jalalluddin
Published: September 2010

Determination of the vapour pressure of ammonium bicarbonate from 28 to 98.4°. Tentative estimation of the maximum sublimation point at 19.5° and of the minimum melting point at 114°.
Spectro‐photometric determination of carboxyhemoglobin
Authors: van Kampen E. J. , Klouwen H.
Published: September 2010

A rapid, simple, and accurate method is given for the quantitative determination of carboxyhemoglobin in blood.
Phosphatidic acids and derivatives: IV). Synthesis of α‐glycerophosphatidic acids, starting from glycerol‐α‐iodohydrin
Authors: Hessel L. W. , Morton I. D. , Todd A. R. , Verkade P. E.
Published: September 2010

Diacylglycerol‐α‐iodohydrins react smoothly with silver dibenzyl phosphate in the presence of benzene, with the formation of diacylglycerol‐α‐phosphoric acid dibenzyl esters. Upon hydrogenolysis in alcoholic suspension or solution in the presence of a palladium/active carbon catalyst the latter substances yield the corresponding diacylglycerol‐α‐phosphoric acids and toluene.
The exchange of chlorine between the green chromium (III) chloride and chloride ions
Authors: van der Straaten H. , Aten A. H. W.
Published: September 2010

The exchange of chlorine between the green chromium (III) chloride and chloride ions in aqueous solution has been investigated using radioactive chlorine 34 and 38 as tracers. Only in very concentrated solutions a slight exchange has been found.
On the theory of aromatic substitution: IV. The orienting influence of substituents in naphthalene derivatives
Authors: Sixma F. L. J.
Published: September 2010

The method previously described 2) for estimating the “inductive” effect 3) of substituents is applied to electrophilic substitution reactions of naphthalene derivatives. It is shown that a + I‐substituent 4) either at carbon atom 1 or 2 directs the entering substituent mainly to the 5‐position; the positions 8 and 4 possess a smaller reactivity. A ‐ I‐substituent at carbon atom 1 directs to the positions 4 and 8, whereas a ‐ I‐substituent at carbon atom 2 orients mainly to the 1‐position. These rules are in accordance with the available experimental data.

The theory is applied more extensively to the substitution reactions of the mono‐, di‐ and tri‐nitronaphthalenes; the agreement with the experimental data is very satisfactory.
Structure of α.ω‐diphenylpolyenes: III Molecular orbital calculations on the members of the series Ph‐(CH = CH)n‐Ph with n = 0, 1, 2, 3, 4, and 5
Authors: Drenth W.
Published: September 2010

The LCAO‐MO method in first approximation was used to calculate for Ph‐(CH = CH)n‐Ph with n = 0, 1, 2, 3, 4, and 5 bond lengths, resonance energies, the frequency of the first u.v. absorption band, and the probability of transition for this band. For the compounds with n = 0, 1, and 2 the calculations were extended to a second approximation. The semiempirical value obtained from heats of combustion for βo′, the exchange integral including overlap for a bond between adjacent carbon atoms in the benzene molecule, amounts to about ‐73 kcal/mole. It is in satisfactory agreement with the theoretically calculated value of ‐77kcal/mole. βo′, from spectral data has the same order of magnitude.
Side reactions in the polymerization of α‐amino acid n‐carbonic anhydrides. Titration data of polyglycine and polyalanine
Authors: Sluyterman L. A. Æ. , Labruyère B.
Published: September 2010

Polyglycine and polyalanine obtained by polymerization of their N‐carbonic anhydrides often appeared to contain more acid groups than amino groups. This is ascribed, at least partly, to the formation of hydantoin groups.

A small amount of 2,5‐diketopiperazine was isolated from polyglycine.

A discussion of the results and their bearing upon the calculation of molecular weights is given.
Sur la condensation des esters maloniques monosubstitués avec les α‐aminopyridines
Authors: Buu‐Hoi Ng. Ph. , Declercq Monique
Published: September 2010

On montre que la condensation de Tschitschibabin des esters maloniques monosubstitués avec la 2‐aminopyridine et la 4‐méthyl‐2‐aminopyridine n'est pas entravée par la présence de radicaux encombrants dans la molécule de ces esters, et que l'on aboutit, dans tous les cas examinés, aux dérivés de l'homopyrimidazole attendus. Ces observations plaident en faveur de l'hypothèse selon laquelle le mécanisme de la condensation de Tschitschibabin comporte l'intervention des formes énoliques des esters maloniques.
Synthesis and stability of o,o′‐dimethoxybenzoyl peroxide
Authors: Crowdle James R. , Osgood Edmond R. , Gaylord Norman G.
Published: September 2010

o,o′‐Dimethoxybenzoyl peroxide (97% purity) has been synthesized in a 50% overall yield from salicylic acid. The compound has been found to be thermally unstable and shock sensitive
Note sur la bromuration de quelques cétones arylaliphatiques
Authors: Rothstein R. , Schneck G. , Binovic K. , Stoven O.
Published: September 2010

La bromuration des éthers benzyliques des dihydroxyphényl alcoylcétones, par la bromo‐succinimide, se fait avec de très bons rendements et sans coupure partielle des groupes benzylés.
Mechanism of the alkaline decomposition of sulphonylnitrosamides: (IInd communication on sulphonylnitrosamides)
Authors: de Boer Th. J. , Backer H. J.
Published: September 2010

The alkaline decomposition of p‐tolylsulphonylmethylnitrosamide with potassium hydroxide in ethyl alcohol yields chiefly diazomethane, together with ethyl and potassium p‐toluenesulphonate. These products are compatible with a pseudo‐catalytic mechanism in which the ethylate ion plays a main role.
The reactivity of halogen atoms occupying positions 3 and 5 in 2,4‐dihydroxypyridine: A new synthesis of 5‐chloro‐2,4‐dihydroxypyridine
Authors: den Hertog H. J. , Combé W. P. , Kolder C. R.
Published: September 2010

A survey is given of the rearrangements occurring during the heating of the monobromo and monochloro derivatives of 2,4‐dihydroxypyridine, substituted at positions 3 or 5, with hydrobromic and hydrochloric acid.

In this connection the reactivity of 3,5‐dibromo‐ and 3,5‐dichloro‐2,4‐dihydroxypyridine has been investigated. It has been found that the halogen atoms at position 3 are replaced by hydrogen in both compounds when they are heated with an aqueous solution of hydrobromic acid to which sodium bisulphite, aniline or another halogen bonding substance is added. When, on the contrary, the dihalogeno derivatives are treated with hydrogen in the presence of a palladium catalyst, the halogen atoms occupying the 5 position are replaced by hydrogen.

These results open up an easy route for the synthesis of 5‐chloro‐2,4‐dihydroxypyridine from 2,4‐dihydroxypyridine as a starting substance.
Additions nucleophiles au bis‐tertiobutylsulfonyl‐acétylène, II. Propriétés du groupe sulfonyle XLIV
Authors: Strating J. , Backer H. J.
Published: September 2010

Un mémoire antérieur a décrit l'addition d'alcools et de mercaptannes au bis‐tertiobutylsulfonyl‐acétylène. La réaction d'amines sur cette disulfone est beaucoup plus vive et, en même temps, plus compliquée. Les produits d'addition que donnent les amines aromatiques sont à même de réagir avec un excès d'amine, en perdant un reste de tertiobutylsulfonyle sous forme d'acide sulfinique. Ainsi il est possible d'introduire successivement deux amines différentes.

Les amines réagissent Également sur les Éthers qui se forment par addition d'alcools à la disulfone acétylénique; l'hydrolyse donne naissance aux mêmes amides que l'on obtient en hydrolysant les adducts d'amines.
The identification of di‐ and polyamines and aminohydroxy compounds as fission products of azodyestuffs
Authors: Frahm E. D. G.
Published: September 2010

Di‐ and polyamines, as well as aminohydroxy compounds in dilute solutions resulting from the reduction of azodyestuffs, can be isolated and identified by benzoylation of such solutions, either immediately or after separation of one or more of the other fission products. When the benzoylation has been carried out properly, the yield of the benzoyl derivatives is almost quantitative. The melting points of several benzoyl compounds, not mentioned in the literature, are tabulated.

The method was successfully applied while investigating the constitutions of many azodyestuffs, mainly of the Chlorantine Fast and the Coprantine ranges and their equivalents.
The meta‐para ratio of the inductive effect in benzene derivatives
Authors: Rooda R. W. , Verkade P. E. , Wepster B. M.
Published: September 2010

Starting from the rate constants of the alkaline hydrolysis of methyl meta‐ and para‐N‐oxide‐dimethylamino benzoate and with the aid of data of various nature from the literature, the generalization is arrived at that as a rule the influence of the negative inductive effect from the meta and from the para position differs little, with some tendency towards predominance of this effect from the meta position.

Some applications of this generalization are discussed.
A new colour reaction for the determination of glycyrrhizic acid, using paper chromatography
Authors: Gootjes J. , Nauta W. Th.
Published: September 2010

A new method is described for the determination of glycyrrhizic acid. Paper chromatography was applied to licorice, and a colour reaction with rhodamine dyes was developed for the detection and estimation of glycyrrhizic acid.
The gravimetric determination of cholesterol in woolwax
Authors: Knol H. W.
Published: September 2010

The analytical determination of cholesterol in woolwax alcohols by means of the formation of an insoluble addition product with digitonin gives unreliable results, caused by the co‐precipitation of the “triterpene” alcohols. 10‐20% of the precipitated fraction may consist of “triterpene” woolwax alcohols. A correction for this co‐precipitation cannot be given, because no connection exists between the contents of cholesterol and “triterpene” alcohols in woolwax. For a more reliable determination of cholesterol the photometrically measured colour reaction of Liebermann‐Burchard should be preferred.
The quantitative determination of small amounts of acetaldehyde
Authors: Maurice M. J. , Rekker R. F.
Published: September 2010

Two compounds, diazosulfanilic acid and phenylhydrazine p. sulfonic acid, known in the literature for the qualitative determination of aldehydes, were investigated for their ability to be used in the quantitative determination of small amounts of acetaldehyde.
Thermal diffusion of liquid mixtures of pure hydrocarbons i. the performance of a microthermal diffusion column
Authors: van Schooten J. , van Nes K.
Published: September 2010

The theoretical approach of separation by thermal diffusion is somewhat hampered by the lack of sufficient experimental data.

In an effort to meet this want, a microthermal diffusion column was constructed, which enables the composition of the mixture to be determined all along the column. This column, which is described in the present paper, has 43 outlets, placed along its length, from which samples can be taken.

With the aid of this column the separation of some binary hydrocarbon mixtures was studied after various time intervals. Results so far have confirmed current theories describing thermal diffusion as a counter current fractionation process.

The degree of separation in the stationary state is expressed by the concentration gradient at the point of inflection of the concentration‐length curve. From this concentration gradient the thermal diffusion constant D′ is calculated for the various mixtures studied.
The action of acid chlorides on 4‐chloro‐ and 4‐hydroxypyridine ‐n‐oxide and some of their derivatives
Authors: den Hertog H. J. , Maas J. , Kolder C. R. , Combé W. P.
Published: September 2010

The action of phosphorus oxychloride and sulphuryl chloride on 4‐chloro‐ and 4‐hydroxypyridine‐N‐oxide and on their 3‐chloro‐derivatives has been investigated.

Under the conditions chosen the acid chlorides reacted differently. Phosphorus oxychloride replaced the hydroxyl group by chlorine and promoted the deoxidation of the N‐oxide group. Sulphuryl chloride removed the oxygen atom of the N‐oxide group, introducing at the same time chlorine at one of the α‐positions; further it replaced the hydrogen atoms at the β‐positions by chlorine, but not the hydroxyl group.

A substance whose analysis pointed to the formula C5Cl7NO was isolated from the reaction mixture obtained by heating 4‐hydroxypyridine‐N‐oxide, its 3‐chloro, 3,5‐dichloro or 3‐nitro derivative with an excess of sulphuryl chloride. It is assumed to be 1,2,2′,3,3′,5,6‐heptachloro‐1,2,3,4‐tetrahydropyridone‐4, inter alia because of its reduction yielding 2,3,5,6‐tetrachloro‐4‐hydroxypyridine. The last‐mentioned compound was identified with preparations synthesized from pentachloropyridine and 4‐amino‐2,3,5,6‐tetrachloropyridine. The substance C5Cl7NO was also obtained when 4‐hydroxypyridine was treated with sulphuryl chloride.
The interaction between urea and carboxylic acids in solution: The ternary systems water ‐ urea ‐ n‐valeric acid and water ‐urea ‐ 2‐methyl butyric acid (isovaleric acid)
Authors: Ketelaar J. A. A. , Loopstra B. O.
Published: September 2010

The liquid miscibility gaps in the ternary systems water‐urea‐n‐valeric add and water‐urea‐2‐methyl butyric add respectively are determined at 25° C.

The heats of mixing of n‐butyric add and of isobutyric acid with an equimolar amount of water and with a concentrated solution of urea in water are determined.

No significant difference in the behaviour of branched and unbranched adds towards urea in solution is observed, contrary to former statements.
The partition of HNO3 between water and three organic solvents
Authors: Kooi J.
Published: September 2010

The partition of nitric acid between water and diethylether, methylisobutyl ketone, and dibutyl carbitol respectively has been measured at 25.0 ± 0.1° C in the range from 1 to 10 N. The experimental data are presented as mass and as concentration (mol/l) partition coefficients. The results seem to be accurate to within 1%.
An improved method for the spectrochemical determination of zinc in blood
Authors: Addink N. W. H.
Published: September 2010

In order to determine the concentration of zinc in blood with greater precision than before, a method has been worked out of which the main points are:

(a) complete evaporation of the metal out of a weighed amount (of 10 mg) of bloodash;

(b) a constant arc temperature independent of a varying sodium content of the bloodash;

(c) a rotating anode of a definite shape.

By using this method concentration values have been determined with a St. dev. of 5%. As for the absolute concentration of zinc in various blood samples, values found in applying the method of successive additions, agreed satisfactorily with those determined chemically.
A Base‐line for nucleic acid turnover in isotopic studies
Authors: Bassir O.
Published: September 2010

In this experiment, the “decay” with time of injected radio‐active phosphorus, P32, in various fractions of the rat liver is studied, with a view to discovering an acid‐soluble fraction which would appear to be an “immediate precursor” of ribonucleic acid and deoxyribonucleic acid.

It is shown that the Specific Activity‐Time curve of liver inorganic phosphate does not satisfy the requirements of an “immediate precursor” of the nucleic acids. On the other hand, a compound, chemically identifiable with adenylic acid, has been shown to be more suitable for use as a base‐line for the turnover of these acids.
N15‐investigations on the mechanism of nitrogen interaction in normal and immobilized organisms
Authors: Heilskov N. S. C. , Schønheyder F. , Olesen K.
Published: September 2010

The mechanism underlying the negative N‐balance provoked by immobilizing bed rest has been studied by means of excretion data for N15 after administration of N15‐labelled glycine to human subjects under normal conditions (N‐equilibrium) and during immobilization (negative N‐balance). The results seem to indicate that the negative N‐balance during immobilization is primarily based upon a reduced synthesis of tissue proteins, while the rate of breakdown of these proteins is unchanged.
Emploi des rayonnements, et en particulier de l'infrarouge, dans l'identification des molecules en biologie
Authors: Guillot Marcel
Published: September 2010

On trouvera un grand nombre de renseignements techniques utiles sur toutes les méthodes dont il est question dans cette conférence dans:

Physical Methods of Organic Chemistry, vol. I, Part II de A. Weissberger; Interscience Publishers Inc., New‐York, 1949.

En ce qu concerne en particulier l'infrarouge, on lira l'article de W. West dans l'ouvrage précédemment indiqué, p. 1332 à 1371.

Sur l'emploi général de l'infrarouge pour l'identification des molécules, on pourra lire la revue d'ensemble de A. Berton, “Les spectres infrarouges en biologie et en pharmacie”, Annales pharmaceutiques françaises, 11, 129, (1953).

Enfin, l'ouvrage de J. Lecomte, “Le Spectre infrarouge”, Edit, de la Société “Journal de Physique”; Les Presses universitaires, Paris, 1928, reste classique, bien que déjà dépassé.

Au sujet des méthodes d'analyse immédiate utilisables, on pourra consulter avec profit le volume V du même ouvrage de Weissberger, qui a été rédigé par H. G. Cassidy (1951).

On trouvera dans ces différentes publications une bibliographie complète de ces questions, bibliographie qui est trop vaste pour que nous puissions la fournir ici.
Acquisitions récentes relatives aux dosages et a l'identification des 17 céto‐stéroides et des corticoides
Authors: Henry R.
Published: September 2010

Aussi bien pour le dosage des corticoïdes que pour celui des 17‐céto Stéroïdes neutres urinaires ou sanguins les méthodes d'hydrolyse biologique sont préférables. La Chromatographie utilisant l'alumine ou la Chromatographie sur papier peuvent être appliquées à la séparation des 17‐ céto Stéroïdes et des corticoïdes. Les produits élués sont caractérisés en utilisant des réactions colorées ou la spectrophotométrie infrarouge et ultraviolette. L'intérêt clinique de ces dosages est succinctement rappelé.
The katharometer in gas analysis
Authors: Coxon R. V. , Banister P. G. , Kay R. H.
Published: September 2010

A Katharometric device has been applied to the problem of securing continuous records of the atmospheric conditions inside incubators during the therapeutic administration of oxygen to newborn infants.
Ein einfacher Apparat zur semiquantitativen Bestimmung von Koproporphyrin im Harn
Authors: Donath W. F.
Published: September 2010

Es wird eine einfache fluorometrische Methode für die semiquantitative Bestimmung von Koproporphyrin im Urin beschrieben. Diese Methode kann sehr gut angewendet werden bei der Ermittlung von Fällen von Bleivergiftung.
Étude des protéines sériques de malades traités avec la clorpromazine, par la méthode de l'èlectrophorèse différentielle, en clinique psychiatrique
Authors: Dubost P. , Pascal Suzette
Published: September 2010

Étude effectuée dans le cadre des recherches poursuivies à la clinique des Maladies Mentales et de l'Encéphale de la Faculté de Médicine de Paris (Pr. Jean Delay) pour dépister les modifications biologiques que pourrait entraîner l'administration prolongée de la clorpromazine, recherches qui seront l'objet d'un mémoire d'ensemble ultérieur. L'électrophorèse différentielle a été pratiquée en même temps sur des malades témoins sans traitement et sur des malades traités à la clorpromazine, examinés soit avant et pendant le traitement, soit seulement en cours de traitement.

L'absence de modifications significatives du chiffre des protéines sériques, au cours d'un traitement prolongé à la clorpromazine, permet de penser que ce mèdicament n'a pas d'action nocive marquée vis‐à‐vis des fonctions protéiques hépatiques.
Die Proteinämie und Proteinurie beim Nephrosesyndrom untersucht mit Hilfe der Papier‐Elektrophorese
Authors: Alvarez Justo Gonzalez , de la Gandara Joaquin Otero
Published: September 2010

Wir studierten mit Hilfe der Papierelektrophorese das elektrophoretische Bild im Blut und Harn bei Individuen mit Nephrosesyndrom. Die Untersuchungen wurden bei Kranken der Madrider Universitätklinik für innere Medizin vorgenommen.
The effect of sex hormones on histaminase measured with a micro‐volumetric method
Authors: Kapeller‐Adler R.
Published: September 2010

Natural oestrogens activate histaminase, unlike the synthetic oestrogens and most of the other steroid hormones and chorionic gonadotrophins which inhibit histaminase. A micromethod that allows comparative investigations of the effect of equimolar solutions of steroids on histaminase extracts has been elaborated and is described with dose‐response curves. The significance of the results obtained with regard to hormonal effects on histaminase activity in normal and toxaemic pregnancy is also discussed.
Synthetic oxytocics V. Quinine derivatives
Authors: Pouwels H. , Veldstra H.
Published: September 2010

Contrary to expectations, based upon a certain structural resemblance between 3‐(piperidyl‐(2)‐methyl‐)indoles (II) and quinine (III), the change from quinine and related alkaloids to their 9‐deoxy bases (viathe 9‐chloro‐9‐deoxy derivatives) does not enhance the oxytocic activity. This activity remains practically constant, whereas these variations in structure cause a total loss of antimalarial activity. By oxidation of the deoxy bases, the unknown carboxylic acids of type IV (oxytocically inactive) were obtained.
Gas‐liquid partition chromatography
Authors: Dijkstra G. , Keppler J. G. , Schols J. A.
Published: September 2010

The identification and determination of different aliphatic substances by means of a suitable system of gas chromatography is described.

Gas‐chromatographic separations of different series of carboxylic acid esters from propionic‐ up to stearic acid ester, alcohols from pentanol up to hexadecanol, and aldehydes from pentanal up to decanal are described.

Silicone grease or paraffin wax is used as the liquid phase with celite as a carrier. The separations have been carried out at temperatures up to 230° C, which made the use of atmospheric pressure at the outlet possible. Hence the fractions separated can be conveniently collected. A quantitative determination of milligram amounts in mixtures of methyl esters is described.

The minimal detectable amounts as estimated for methyl propionate are of the order of micrograms.
Gas hydrates ‐ approximate relations between heat of formation, composition and equilibrium temperature lowering by “inhibitors”
Authors: Pieroen A. P.
Published: September 2010

Relations are derived between the heat of formation of a gas hydrate, its composition and the depression of the three‐phase equilibrium temperature upon addition of a “third component”, such as an alcohol. Although none of these equations is fully exact they are in reasonable agreement with experimental data. The treatment is limited to constant pressures.
The oxidation of phenols with copper‐amine catalysts and its relation to the mode of action of tyrosinase: II. The oxidation of naphthols with tertiary amines as catalysts
Authors: Brackman W. , Havinga E.
Published: September 2010

In this paper the catalytic oxidation of a number of naphthols is described, copper‐collidine and copper‐pyridine complexes being used as catalysts.

Generally speaking two types of reactions must be considered. The first type involves a direct oxidation of the naphthol by the cupric complex to free radicals which dimerize and give rise to dinaphthols. Some of these are oxidized further to naphthalene analogues of diphenoquinone (dinaphthones and bisnaphthalene indigo's). All these reactions may be accomplished by the cupric complex itself, and the function of oxygen is simply to regenerate the cupric‐ from the cuprous state.

In the second type of reactions, which involve the formation of 1,4‐naphthaquinone derivatives, oxygen (or hydrogen peroxide formed from it) probably plays a more specific rôle. Hydrogen peroxide may also be responsible for some unidentified products formed from the dinaphthol derivatives.

The naphthols investigated were: naphthol‐1, naphthol‐2, 2‐ethyl‐1‐naphthol, 4‐methyl‐1‐naphthol, 2‐ and 4‐chloro‐1‐naphthol. The products are listed in table 1. The redox potentials of 4‐(2′‐hydroxy‐1′‐naphthyl)‐1,2‐naphthaquinone and of diethyldinaphthone have been measured.

The spectra of bis‐methylnaphthalene‐indigo and of natural indigo appear to be strikingly similar.

The following new compounds are described: 4‐(di‐β‐naphthoxyl)‐1,2‐naphthaquinone and its phenazine, bis‐4‐chloronaphthalene indigo, 2,2′‐dichlorodinaphthone, bis‐4‐methylnaphthalene indigo, a black compound (C30H18O4)X.
On the reaction of phenylethyne with formaldehyde On the reaction of phenylethyne with formaldehyde
Authors: Beets M. G. J. , Heeringa L. G.
Published: September 2010

The acid‐catalyzed reaction of phenylethyne with formaldehyde has been studied. From the complex reaction mixture a number of compounds have been isolated. Their structures and the mechanism of their formation are discussed. Preliminary results on the acid‐ and alkali‐catalyzed reactions of acetophenone with formaldehyde are reported.
Plant pigments in digestion trial studies
Authors: Deijs W. B. , Bosman Maria S. M.
Published: September 2010

The plant pigments (“chromogens”) in extracts of fresh grass and feces from cows in 85 per cent (by volume) acetone, applied as digestion trial markers, have been separated and determined chromatographically. In the extracts of fresh grass chlorophyll (converted into pheophytin by oxalic acid), carotene, xanthophyll, and a small amount of porphyrins could be determined. In feces pheophytin, carotene, xanthophyll, phylloerythrin, and other porphyrins not yet defined could be detected.

The application of naturally occurring plant pigments as Indicators in the determination of the digestibility of feed by ruminants has been discussed.
Studies on tautomerism V: Some remarks on the tautomeric equilibrium, dimerization, and ionization of quinone monoximes (nitrosophenols)
Authors: Schors A. , Kraaijeveld A. , Havinga E.
Published: September 2010

Measurements of absorption spectra in the ultra‐violet as well as in the visible (red) region were used to study the tautomeric equilibria in the case of p‐benzoquinone monoxime, 3‐chlorobenzoquinone‐4‐monoxime, naphthoquinone monoxime, and anthraquinone monoxime.

In die case of the benzoquinone monoxime ‐ and less easily also with the chloroquinone monoxime ‐ the presence of the nitrosophenol form could be traced and its amount could be estimated. This was not possible with the naphthoquinone monoxime and the anthraquinone monoxime, which in solution seem to consist almost completely of the quinonoid form. A short theoretical comment is given.

Experimental results and conclusions concerning the spectra of nitroso‐benzenes in general are discussed. Complications that may be caused by dimerization phenomena and by electrolytic dissociation of the compounds investigated were studied.

Some nitrosophenols were found to be rapidly etherified at room temperature in methanol (and less quickly also in other alcohols) which had been acidified by addition of a few per cent, of concentrated hydrochloric acid.
Eine genaue Methode zur Papierelektrophoretischen Auswertung von Proteinen
Authors: de Jong E. B. M.
Published: September 2010

Für die Anfärbung der Eiweissfraktionen auf Filtrierpapier wird Amidoschwarz benutzt, weil dieser Farbstoff ein sehr gutes Bindungsvermögen mit Protein hat und unabhängig von der Auswaschmethode mit den verschiedenen Eiweissfraktionen ein konstantes Bindungsverhältnis aufweist.

Der Nachteil der schweren Auswaschbarkeit des Amidoschwarz an der nicht mit Eiweiss beladenen Stelle, wird beseitigt indem man einen einfachen Apparat gebraucht, worin die Papierstreifen bei 65° C mit 1%‐iger Essigsäure ausgewaschen werden.

Nach eingehenden Untersuchungen der photometrischen Auswertung, haben wir die Folgerung gezogen, dass diese Methode aus prinzipiellen Gründen verwerflich ist.

Deshalb wird die Elutionsmethode benutzt. Die Ursache der Unbeständigkeit von Amidoschwarz in Lauge wird untersucht, weil diese Unbeständigkeit selbstverständlich eine genaue Bestimmungsmethode verhindert.

Es wurde gefunden, dass die Unbeständigkeit ihre Ursache in der Anwesenheit von Schwermetall‐ionen in Lauge hat, was durch Zufügung von “Komplexon” völlig beseitigt werden kann.

Eiweissmengen bis 0.75 mg auf 2 cm2 Filtrierpapier weisen ein genaues lineares Verhältnis auf mit der Menge gebundenem Farbstoff.

Die verschiedenen Eiweissfraktionen können nach Papierelektrophoretischer Trennung mit einer sehr geringen Fehler bestimmt werden.

Für Alb. ± 0.5; α1 ± 0.3; α2 ± 0.3; β ± 0.3 und γ ± 0.4 rel. Prozente.

Mit unserer Methode konnten bei 45 gesunden Personen Normalwerte bestimmt werden.

Albumin 69.8 ± 1.5; α1‐Glob. 3.3 ± 03; α2‐Glob. 6.3 ± 0.6; β‐Glob. 7.9 ± 0.8 und γ‐Glob. 12.9 ± 1.3.
Fibre‐forming polyalkylene ureas: I. General remarks on the chemical preparation and a study of the structure and the mechanism of formation
Authors: van der Kerk G. J. M. , Overmars H. G. J. , van der Want G. M.
Published: September 2010

The chemical preparation is described of linear polyalkene ureas from aliphatic α,ω‐diamines and carbon oxysulphide. Using chemical and physical methods, the mechanism of the poly‐condensation reaction is studied and a satisfactory picture of the structure and of the mode of formation is obtained.

After melt‐spinning the products can be cold‐stretched to form strong and flexible fibres
Synthesis of di‐amino‐salicil and some of its derivatives
Authors: Berends W. , Waisvisz J. M. , Mulder A. K. J.
Published: September 2010

From the work of R. Kuhn et al. it appeared that brominated derivatives of salicil have a high anti‐bacterial activity in vitro, but that in vivo they show only little activity as a result of serum‐binding. Base‐substituted phenols are usually bound by serum to a smaller extent. Therefore, an amino‐substituted bromo‐salicil was synthesized. A water soluble derivative of this compound was also prepared.
Dehydration of 17α‐hydroxy‐20‐ketopregnanes
Authors: Szpilfogel S. A. , Gerris V.
Published: September 2010

During an investigation on compounds related to cortisone the dehydration of various 17α‐hydroxy‐20‐ketopregnanes was studied.

In a recent paper Bernstein et al.1) reported on the elimination of 17α‐hydroxy groups adjacent to a 20‐ketal group. These hydroxy groups were known to be stable towards phosphorus oxychloride‐pyridine at room temperature2), but with thionyl chloride‐pyridine the desired Δ16‐steroids were formed. This publication covers part of the work carried on for some time in this laboratory and prompts us to give our additional results.
Über Glutamal‐5, Aspartal‐4 und einige hiervon Abgeleitete Peptide: Untersuchungen in Beziehung zu Eiweiss‐Problemen VII
Authors: Kög F. , Schopman W.
Published: September 2010

Der γ‐Halbaldehyd von DL‐Glutaminsäure und der β‐Halbaldehyd von DL‐Asparaginsäure wurden durch Zerlegung der entsprechenden Mercaptale dargestellt. Letztere dienten weiterhin zur Synthese der Aldehydopeptide Glycyl‐DL‐glutamal‐5, Glycyl‐DL‐glutamal‐5‐yl‐glycin und Glycyl‐DL‐aspartal‐4. Aus dem Verhalten dieser Peptide bei der Hydrolyse mit Salzsäure ist zu folgern, dass die genannten Aldehyde ‐ falls sie als Baustein von Proteinen auftreten würden ‐ in den entsprechenden Hydrolysaten nicht ohne weiteres nachweisbar sind.
Synthesis of α‐phenacyl‐N‐methylpiperidine (“sedamine‐ketone”) under pseudo‐physiological conditions.(Short communication)
Authors: Beyerman H. C. , Enthoven P. H.
Published: September 2010

The condensation of N‐methyl‐α‐piperidol (I), which we consider to be a cyclic tautomer of 5‐methylaminopentanal (II), with benzoylacetic acid is reported to give α‐phenacyl‐N‐methylpiperidine (“Sedamine‐ketone”, IVa) in yields up to 50% depending on the pH of the reaction mixture.
The effect of long‐chain alcohols on the properties of sodium laurate solutions: Part I. Surface tension
Authors: Harva O.
Published: September 2010

The surface tensions of sodium laurate solutions containing aliphatic alcohols from hexanol up to decanol have been measured at pH 11. The occurrence of break points in the surface‐tension concentration curves for higher alcohol concentrations are explained by assuming complex formation to occur between the laurate anion and the alcohol molecule.
Reactions of ethyl bromide and aluminium bromide. I. Bromine exchange
Authors: Sixma F. L. J. , Hendriks H. , Holtzapffel D.
Published: September 2010

The kinetics of the exchange reaction of bromine atoms between ethyl bromide‐ [82Br] and aluminium bromide in carbon disulphide has been studied. The reaction rate is proportional to the ethyl bromide concentration and to the square of the aluminium bromide concentration. The energy of activation amounts to 11.7 kcal/mole (±7%).

It is probable that no carbonium ions are involved in the reaction.

The rate of the exchange reaction is very low in such solvents as nitrobenzene, nitromethane, ether and acetonitrile. This is ascribed to the formation of rather strong complexes between these solvents and aluminium bromide.
Synthèse de quelques nouveaux éthylpolyméthylphénols
Authors: Buu‐Hoï N. P. , Sy Michel , Lejeune Guy
Published: September 2010

A l'aide d'une méthode de récurrence comprenant des formylations par la diméthylformiamide, des réductions d'aldéhydes par l'hydrate d'hydrazine, et des déméthylations des polyalkylanisoles obtenus par le chlorhydrate de pyridine, on a préparé le 3‐éthyl‐4,5‐diméthylphénol, le 3‐éthyl‐2,4,5,6‐tétra‐méthylphénol, et le 1,3‐diméthyl‐5,6,7,8‐tétrahydro‐2‐naphtol; le 2‐éthyl‐3,4,5‐triméthylphénol a été préparé à partir du 2‐acétyl‐3,4,5‐triméthylanisole.
Studies on vitamin D and related compounds V: Corroboration of the scheme proposed for the photochemical conversion of the provitamins D, in particular with regard to the place of the previtamins D
Authors: Havinga E. , Verloop A. , Koevoet A. L.
Published: September 2010

In continuation of the irradiation experiments with mixtures of labelled provitamin D and inactive lumisterol and tachysterol, which led to the rejection of the traditional reaction scheme and the introduction of a new scheme for the photochemical conversion of provitamin D 1) 2), mixtures of C14‐labelled ergosterol and inactive previtamin D2 were irradiated and the resulting products analysed. Moreover, complementary spectrophotometric investigations into the photochemical conversion of previtamin D2 were carried out. The results confirmed the non‐validity of the schemes which assign to one of the irradiation products of provitamin D the part of an essential intermediate for the formation of the other products. Particularly, the investigations confirmed that previtamin D2 does not function as an essential intermediate with respect to the formation of tachysterol2 from ergo‐sterol 4) 5). The possibility is mentioned that the unstable intermediate which holds a central position in the proposed scheme in its simplest form 1), might be a triplet state.
Microbiological preparation of substance U from cortisone
Authors: Szpilfogel S. A. , de Winter M. S. , Alsche W. J.
Published: September 2010

Among the many transformations of steroids by microorganisms reported in recent years were those using Fusarium strains1) 2). With progesterone as the substrate the main product isolated was Δ1,4‐androstadiene‐3,17‐dione. The same product has been found to be formed from Δ4‐androstene‐3,17‐dione, Δ5‐3β‐hydroxypregnene‐20‐one and Δ5‐3β‐hydroxyandrostene‐17‐one1). In contrast with the acetyl side‐chain of progesterone the dihydroxyacetone side‐chain of cortisone has not been attacked and cortisone was dehydrated to prednisone (1,2‐dehydrocortisone) 2).
Complex coacervation. III. Thermodynamic calculations on three‐component systems
Authors: Voorn M. J.
Published: September 2010

Using the model of complex coacervation, described in parts I and II, a phase diagram is calculated, giving the influence of electrolytes on complex coacervation in a mixture of two poly‐electrolytes in equivalent amounts. The suppressive action of salts is explained as a result of electrical interactions.
Electrophoresis of polyelectrolytes with partial drainage
Authors: Overbeek J. Th. G. , Stigter D.
Published: September 2010

The electrophoretic velocity of a uniformly charged porous sphere in a salt solution is considered to be composed of three contributions. These are:

a motion caused by that part of the charge which is exactly compensated by counter‐ions within the porous sphere.

a motion caused by the net charge of the porous sphere.

a motion caused by the counter‐ions outside the sphere.

The influence of relaxation is left out of consideration. The presence of the counter‐ions is shown to lead to a relatively high degree of draining. In solutions of high ionic strength, where the porous sphere model fails, polyelectrolyte coils are shown to be freely drained and the application of Henry's theory of electrophoresis of a cylindrical rod is discussed.