bluuebunny/crossref_metadata_2025 huggingface dataset:
Fragmentierung eines aliphatischen para-Chinoläthers
Authors: Rieker Anton , Zeller Norbert
Published: February 2015

Bei der Pyrolyse und Säurespaltung des aliphatischen p-Chinoläthers 1 b bildet sich im Gegensatz zu Beobachtungen an aromatischen p-Chinoläthern kein o-Hydroxy-phenyläther 2 b. Vielmehr entstehen durch Ablösung von Isobutylen der p-Hydroxyphenyläther 4b und durch Eliminierung von Formaldehyd 2.4.6-Tri-tert.-butyl-phenol (5). Analog verläuft die Fragmentierung von 1 b im Massenspektrometer. Dies wird auf das Unvermögen von 1 b zurückgeführt, sich in den stellungsisomeren o-Chinoläther 3 b umzulagern, der zu 2 b zerfallen müßte. Im Gegensatz dazu ergibt 1 b bei der Photolyse (254 nm) in absol. Äther neben 5 drei weitere Verbindungen, die durch Umordnung des Ringkohlenstoffskeletts entstehen: das Bicyclohexenon 13, das zu 2b isomere o-Methoxyphenol 11 und das Cyclohexadienon-Derivat 12. Das gleichzeitig isolierte Cyclopentenon 14 bildet sich vermutlich erst bei der Aufarbeitung durch Fragmentierung an Kieselgel.
Untersuchungen zur Reaktion der Alkoholdehydrogenasen mit Tritium-markierten Substraten
Authors: Palm Dieter , Fiedler Tankred , Ruhrseitz Dorothea
Published: February 2015

[1,1-T]-ethanol,:1,1-T]-propanol and [1,1-T]-butanol exhibit small isotope effects (kH/kT=1.3-1.8) in the liver alcohol dehydrogenase catalyzed reaction NAD® + alcohol ⇌aldehyde +NADH+H®. Presence of semicarbazide (with [1,1-T] -ethanol) or substrat inhibition (with [1,1-T] -butanol, 2.10-2-m.) raises the isotope effect (up to 4.1 at 25 °C) by introducing partial irreversibility to the interconversion step of the ternary complexes. This is in agreement with the Theorell-Chance mechanism as extended by DALZIEL. Thus, isotope effect determinations confirm both, the presence of ternary complexes and their kinetic insignificance for lower aliphatic substrates.

The results are markedly different from analogous kinetics with the yeast enzyme.
Vergleichend chemische Untersuchungen der Inhaltsstoffe der Pygidialwehrblasen von Carabiden
Authors: Schildknecht H. , Winkler H. , Maschwitz U.
Published: February 2015

In Ergänzung zu früheren Arbeiten wurden die Inhaltsstoffe der Pygidialwehrblasen von 69 verschiedenen Laufkäferarten durch Dünnschichtchromatographie, Hochspannungs-Elektrophorese, Gaschromatographie, Massen- und IR-Spektroskopie untersucht. Es zeigte sich, daß neben Ameisensäure, Methacrylsäure und Tiglinsäure auch n-Undecan sowie teilweise n-Decan und n-Tridecan gespeichert werden kann. Als weitere Sekretbestandteile konnten iso-Valerian- und iso-Buttersäure sowie p-Benzochinon, 2-Methyl-p-benzochinon und 2-Methyl-3-methoxy-p-benzochinon und m-Kresol nachgewiesen werden.
Über die gerichtete Aufnahme des Biopterins im Organismus I.
Authors: Hanser Gisela , Rembold Heinz
Published: February 2015

C14 labelled Biopterin and Neopterin, when fed to larval stages of Queen and Worker bees, behave similarly and are incorporated into different organs. During metamorphosis and imaginal development, the accumulation of the radioactive pterins is found in places of high metabolic activity such as the eyes, wings, legs. They are also found in the tracheal epithelium, in the wing muscles and the ovaries. In tissues of high cellular activity the radioactivity is found in the nuclei. The concentration of the administered labelled Biopterin and Neopterin into the imaginal cuticle at the time of sclerotization and pigmentation, as well as their directed uptake by the peripheral ganglion sheath of the central nervous system points to the functional importance of these pterins as cofactors of phenylalanine hydroxylase and respectively of tryptophane hydroxylase in insects.
Über die strukturabhängige hämolytische Aktivität einiger Cholin-Phosphatide
Authors: Arnold D. , Weltzien H. U.
Published: February 2015

Eine Anzahl synthetischer Cholinphosphatide wurde hinsichtlich ihrer hämolytischen Wirksamkeit untersucht. Die Lyse der Erythrocyten wurde dabei sowohl in ihrem zeitlichen Verlauf verfolgt, wie auch durch Endpunktsbestimmung bei verschiedenen Konzentrationen quantitativ erfaßt.

Ein direkter Zusammenhang zwischen der Grenzflächenaktivität und der hämolytischen Wirksamkeit der Substanzen besteht nicht. Innerhalb homologer Verbindungsreihen wird dagegen durch die Kettenlänge des apolaren Teils im Molekül eine scharfe Grenze zwischen lytischen und nicht-lytischen Verbindungen gezogen. So zeigt beispielsweise das sehr stark grenzflächenaktive Dipelargonoyl-α-lecithin gegenüber Humanerythrocyten keinerlei hämolytische Wirksamkeit, während Dicaprinoyl-α-lecithin bei gleicher Grenzflächenaktivität eine deutliche Hämolyse verursacht.

Bei einigen der untersuchten Phosphatide wurde überdies ein diskontinuierlicher, zweistufiger Verlauf der Zellzerstörung beobachtet.
RNS-Zusammensetzung in Weidenröschen
Authors: Fritz Hans-Georg
Published: February 2015

The nucleotide composition of whole cell RNA from Epilobium leaves at different developmental stages was determined during various growing periods. Differences in the nucleotide composition were found to be correlated with the RNA content of the leaves and with the development of the plants. An expected correlation of the base-composition of RNA with the extrachromosomal genetic constitution of the investigated plants has not been demonstrated because of the different physiological behaviour of these plants. An RNA-fraction, not hydrolysable with 0,3 N KOH proved to be partially responsible for the observed differences in the RNA-nucleotide composition.
Zur Strahleninaktivierung von Ribonuclease
Authors: Jung Horst , Schüssler Helga
Published: February 2015

Dry ribonuclease was irradiated with 60Co gamma radiation in vacuo, under oxygen atmosphere, and at 77 °K. By chromatography on Sephadex G-50 active ribonuclease was separated from inactive radiation products. From the elution pattern and by ultracentrifugation it was shown that mainly unfolded dimers are formed by gamma irradiation of dry ribonuclease. Amino acid analysis of these various products shows that in all components cystine, methionine, tyrosine, phenylalanine, lysine, and histidine are destroyed with increasing dose whereas glycine shows a small increase. Thus, in ribonuclease irradiated in the dry state the same amino acids are changed as was found after irradiation in aqueous solutions. The radiosensitivity of dry ribonuclease shows an increase by the presence of oxygen of about 2 and a decrease at low temperature in vacuo of about 5. The same factors were also found for the alteration of amino acids, which means that under various experimental conditions amino acid destruction is proportional to loss of enzymatic activity of ribonuclease. The observed selectivity of amino acid destruction may be explained by energy migration or by the attack of atomic hydrogen liberated at random from the molecule. The total number of amino acids destroyed per ribonuclease molecule increases with dose. In enzymatically inactive products this value is always higher by one amino acid residue than in the active components. From this result and from the increase with dose it is concluded that after destruction of one amino acid residue the ribonuclease molecule has a probability (not depending on dose of irradiation) of 0.45 to become inactivated whereas in 55 per cent of all cases the molecule maintains its enzymatic activity.
Strahleninaktivierung von Ribonuclease bei erhöhten Temperaturen und unterschiedlichen Dosisraten
Authors: Kürzinger Klaus , Jung Horst
Published: February 2015

The radiosensitivity of dry ribonuclease was determined at various temperatures between 120 °K and 440 °K using 2 MeV protons. Within this temperature range the inactivation cross section S (T) of ribonuclease may be described as a function of temperature by the expression S(T) = (1.28 + 16·e-1000/RT+14000·e-6500/7RT)·10-14 cm2 .

This result indicates that the observed radiation damage to ribonuclease is produced by three different mechanisms, one being independent of temperature, the other two having apparent activation energies of 1 kcal/mole and 6.5 kcal/mole, respectively. From these relatively small activation energies the conclusion may be drawn that radical reactions contribute to the inactivation of enzymes in the dry state. Experiments with Co gamma radiation showed that the radiosensitivity of ribonuclease at 77 °K depends on dose rate; at room temperature a dose rate effect was not observed.
On the X-Ray Inactivation at Various Temperatures of Trypsin in Dry State and Aqueous Solution
Authors: Oksmo Øyvind , Brustad Tor
Published: February 2015

The X-ray sensitivity of trypsin has been studied both in dry state and in dilute solution (0.1 mg/ml) of 10-3 N HCl, as a function of the sample temperature during irradiation. Oxygen present during irradiation acts as a sensitizer when the exposure is carried out in frozen aqueous solution as well as in dry state, but it acts as a protector when the enzyme solution is exposed at room temperature. There is a considerable indirect effect when trypsin is exposed in frozen aqueous solution, above 200 °K, and even at 77 °K a small indirect effect is apparent.

When trypsin is exposed in 10-3 N HCl at room temperature about 85 per cent of the indirect effect is eliminated when the solution is saturated with O2 , (known as an effective scavenger for e ⊖
aq and H) and most of the remaining indirect effect is eliminated if the enzyme solution also contains 100 mM C2H3OH (known as an effective OH scavenger).
Zuckerbausteine, Chemotypen und Serotypen der Leptospiren
Authors: Parnas J. , Poplawski S. , Cybulska M. T. , Książek A.
Published: February 2015

Wir berichten hier über die Chemotypen serologisch verschiedener pathogener und saprophytärer Leptospiren. Alle Leptospiren, pathogene und saprophytäre (L. biflexa Patoc), wie deren Polysaccharid-Fraktionen sind in der Zusammensetzung der Zuckerbausteine fast identisch. Das gleiche gilt für die Aminosäuren.

Das bedeutet, daß das Genus Leptospira, das 13 Haupt-Serotypen besitz, durch nur einen Chemotyp charakterisiert ist; ebenso ließ sich nur ein Infrarottyp nachweisen.
Zur spektroskopischen Untersuchung der Kinetik chemischer Reaktionen
Authors: Mauser Heinz
Published: February 2015

Es wird untersucht, welche Informationen spektroskopische Messungen über Zahl und Art der Teilreaktionen geben können. In diesem ersten Teil wird die Bedeutung von isosbestischen Punkten kritisch untersucht. Gleichzeitig werden die Grundlagen zum Verständnis einer neuen spektroskopischen Methode zur kinetischen Analyse erarbeitet.
XVIII. Isolation of hörhammerinine, a new alkaloid from C. lanceus (Apocynaceae)
Authors: Farnsworth Norman R. , Loub William D. , Blomster Ralph N. , Abraham Donald J.
Published: February 2015

Catharanthus lanceus Boj. ex A. D.C. leaves have yielded a new α-methyleneindoline alkaloid for which the name hörhammerinine is proposed. In addition, several other alkaloids were isolated, but their presence in this plant had been previously recorded, i.e. ajmalicine, leurosine, pericyclivine, yohimbine, perivine.
Nachweis der Ferredoxin-NADP-Reduktase in der Oberfläche des Chloroplasten-Lamellarsystems mit Hilfe spezifischer Antikörper
Authors: Berzborn R.
Published: February 2015

Antisera against purified ferredoxin-NADP reductase (E.C.1.6.1.1) inhibited photosynthetic NADP-reduction and NADPH2 diaphorase activity of the enzyme. The antisera contained precipitating antibodies against the enzyme. One of the precipitin lines visible after immunoelectrophoretic analysis of the purified reductase was shown to contain diaphorase activity.

The antisera against reductase did not agglutinate isolated lamellar systems of chloroplasts directly. Combination of antibodies to reductase, however, with bound reductase in the surface of lamellar systems could be demonstrated and indirect agglutination was observed, when the lamellar systems were incubated with an antiserum against reductase and when subsequently reductase or an antiserum to rabbit-γ-globulin was added.

These findings indicate, that at least one antigenic determinant of ferredoxin-NADP reductase is accessible to antibodies at the surface of the lamellar system of chloroplasts. Probably this surface is not plane, but possesses protrusions or deepenings of at least half the length of an antibody molecule (ca. 100 A). In these cavities one or more determinants of bound reductase would be located.
Optische Absorptionsspektren strahlenchemisch erzeugter Molekelanionen einiger Heteroaromaten
Authors: Wendenburg Jürgen , Möckel Hermann
Published: February 2015

Die einfach negativ geladenen Molekelanionen des Fluorens und Indens sowie die der entsprechenden O-, NH- und S-Heteroaromaten werden strahlenchemisch erzeugt und durch ihre optischen Absorptionsspektren nachgewiesen. Die Reduktion der in Methyltetrahydrofuran gelösten Verbindungen erfolgt durch die aus der Ionisation des Lösungsmittels stammenden Elektronen. Fluoren, Carbazol und Inodl ließen sich nur auf diese Weise zu den Molekelionen reduzieren, eine Reduktion mit Alkalimetall war nicht möglich. Ferner wird die strahlenchemische Erzeugung der Monoanionen des Diphenyloxids und -sulfids sowie die von α,α′-Dipyridyl, Chinolin, Isochinolin und Acridin beschrieben.
Berechnung von Ionisierungsenergien aus Redoxpotentialen
Authors: Stanienda A.
Published: February 2015

Ionization energies and electron affinities of organic and inorganic substances are obtainable from reversible anodic and cathodic half-wave potentials, solvation energies and the electron work function potential of the electrode metal. Solvation energies were calculated using a modified Born equation in which the molecular radius was corrected for the ionization energy. It is possible to compute the first ionization potential of organic compounds with a deviation from experimental data of less than 3 per cent. The calculated electron-affinities do not agree with values given in the literature but are equal to the difference in energy between the first excited state and ionization potential.

Electron work function potential of platinum measured by an indirect method was found to be 4,43 ev.
Semi-micro Determination of Nitro Compounds with Vanadium(II) Sulphate
Authors: Chawla K. L. , Tandon J. P.
Published: February 2015

Direct potentiometric methods for the semi-micro determination of easily reducible nitro compounds with vanadium (II) sulphate have been described. It has been shown that the position and nature of the substituents in the benzene ring effect the rate of reduction.
Tritium — Markierung des Sexuallockstoffes Bombykol
Authors: Kasang Gerhard
Published: February 2015

Durch katalytische Tritiierung von Hexadecen- (10-trans) -in- (12) -ol- (1) gelang die Synthese von hoch markiertem [12.13-3H] -Hexadecadien- (10-trans,12-cis) -ol- (1).
The Infrared Absorption Spectra of Some Samarium Diketo-ester Complexes
Authors: Tandon S. P. , Mehta P. C.
Published: February 2015

Infrared absorption spectra of some four- and five-coordinated (ethyl 1-methyl acetoacetate) complexes of trivalent samarium have been studied in the region 4000 - 250 cm-1 for the first time. About twenty bands in each chelate have been observed and assigned to different modes of vibration. A study of relative frequency shifts of CO stretching vibrations reveals that the metal-oxygen bonds in all the complexes are nearly of the same strength. The vibrational frequencies, with few exceptions, are found to be nearly independent of the coordination number of the metal.
Absolute IR-Intensitäten der ν (PO)-Schwingung und PO-Bindungsdipolmomente von Phosphorylverbindungen
Authors: Schulze H. , Müller A.
Published: February 2015

Zwischen den absoluten IR-Intensitäten der ν (PO) -Bande verschiedener Phosphorylverbindungen und der Wellenzahl von ν (PO) besteht annähernd eine lineare Abhängigkeit. Für die aus den Intensitätswerten abgeschätzten Bindungsdipolmomente der PO-Bindung gilt das gleiche. Dies wird bindungstheoretisch interpretiert.
Studien zur Penetration des Fungistatikums 35S-4-Chlorbenzyl-isothiocyanat an tierischer Haut I.
Authors: Dedek Wolfgang , Wenzel Klaus-Dieter , Grahl Rolf
Published: February 2015

Der Einfluß unterschiedlicher Lösungsmittel (synthetische Fettsäureester, fette Öle, Paraffinöl, Aceton und DMSO) auf die Penetration von 35S-4-Chlorbenzyl-isothiocyanat an Rinderhaut wurde in Modellversuchen in vitro geprüft. Autoradiographien von Gefrierschnitten der Haut sowie die resorbierte 35S-Aktivität zeigten übereinstimmend, daß die Hauptmenge des Wirkstoffes in den oberen Hautschichten verbleibt und nur maximal 0,9% resorbiert werden. Der Lösungsmitteleinfluß ist sehr gering; Paraffinöl und DMSO zeigen die größten Eindringtiefen.
Der Einfluß aromatischer Substituenten auf die Lage der Si-S-Valenzschwingung
Authors: Fehér F. , Goller H.
Published: February 2015

Es wurden die IR-Spektren von Triphenylsilyl-, Tri-p-tolylsilyl- und Tribenzylsilyl-Schwefelver-bindungen aufgenommen. Die Si-S-Valenzschwingungen dieser Verbindungen, die in folgenden Bereichen auftreten: Triphenylsilyl-Derivate 518 -572 c-1, Tri-p-tolylsilyl-Derivate 519 -556 cm-1, Tribenzylsilyl-Derivate 493 -530 cm-1, werden diskutiert.
Nuclear Magnetic Resonance Studies of Internal Rotation
Authors: Spassov S. L. , Buzova Ts. , Chorbanov B.
Published: February 2015

The activation free energies of the hindered internal rotation around the C-N bond for N,N-dimethylcinnamamide, N,N-dimethylcrotonamide, and N,N-dimethylsorbinamide obtained by the NMR line-shape method are 16.5, 14.9, and 16.2 kcal/mole, respectively. The relation between these values and the structure of the compounds is discussed.
Zur Interaktion von Anthracyclinen und Anthracyclinonen mit DNS / Interaction of Anthracyclines and Anthracyclinones with DNA
Authors: Berg H. , Eckardt K.
Published: February 2015

It was shown by the polarographic data of the complexes between antracycline antibiotics and DNA that in contrast to their biological inactive aglycones and other antracyclinones, a cooperative interaction of the intercalating chromophore as well as the sugar residue of the anthracycline molecules, is generally responsible for the complex formation with DNA.

The high complex binding constants of the antracyclines daunomycin, nogalamycin, galirubin A and galirubin B measured in dimethylsulfoxid-buffer solution are in the same order of magnitude as those of actinomycins. On the other hand, only a weak binding ability of the aglycones daunomycinon, ε-pyrromycinon and aklavinon, as well as of other investigated anthracyclinones and model hydroxyanthraquinones, could be observed.

No significant influence of the number and positions of the chromophore hydroxyls could be noticed.

The results suggest that the first outerphase addition of the sugar residues to the backbone of the helix gives the necessary space of time for the slower intercalation process of the planar chromophore.

In the case of denatured DNA, the antibiotic-DNA-complex has a lowered stability.

The important role of the sugar residue for the binding mechanism strongly suggests that modifications of the nature and position of the basic sugar residue should be most valuable for the synthesis of new effective anthracyclines.
Rise time of the absorption changes of chlorophyll-aI and carotenoids in photosynthesis
Authors: Witt K. , Wolff Ch.
Published: February 2015

With the aid of a repetitive laser giant pulse photometer the rise times of two primary events in photosynthesis have been measured: a) The oxidation of chlorophyll-aI takes place in times shorter than 20 ns. b) The formation of metastable carotenoids is faster than 25 ns.
The Infrared Absorption Spectra of Some Samarium Chelates
Authors: Tandon S. P. , Mehta P. C. , Kapoor R. N. , Misra S. N.
Published: February 2015

The infrared absorption of samarium (di-isopropoxy) mono dibenzoylmethide [Sm (ΟΡr
i) 2DBM] and samarium tris dibenzoylmethide [Sm(DBM)3] in the region 4000 - 250 cm-1 have been studied. About 25 bands in each chelate have been observed and assigned to different modes of vibrations. The number of metal-oxygen vibration modes of the chelates suggest Vh and D3 sym. metries for Sm (OPr
i) 2DBM and Sm (DBM) 3 respectively. The relative frequency shifts of CO and CC stretching modes indicate that the metal-oxygen bonding in Sm(DBM)3 is relatively stronger than in Sm (OPr
i) 2DBM.
Kinetische Untersuchung der Chemilumineszenz von 7-Dimethyl-amino-naphthalin-1.2-dicarbonsäurehydrazid in wäßrig alkalischem Wasserstoffperoxid in Gegenwart von Hämin / Kinetic Investigation of the Chemoluminescence of 7-Dimethyl-amino-naphthalin-1,2-dicarbonic-acid-hydrazid in aqueous alcaline H2O2 in Presence of Hemin
Authors: Eicke Hans-Friedrich , Fiege Helmut , Gundermann Karl-Dietrich
Published: February 2015

The chemoluminescence-system: DNH/NaOHaq/H2O2/hemin was investigated with the help of a “stopped-flow-technique”. By use of an optical cut-off-filter the chemoluminescence- (514 nm), and the absorptionband (325 nm) resp. could be separated which proved impossible with luminol. In this way we could follow the temporal change of chemoluminescence and of absorption of DNH: the latter dropped coutinually with progress of the reaction while the chemoluminescence-intensity passed through a maximum before it decreased according to the same rate law (pseudo first order conditions as for DNH) which governs the absorption change of DNH. The oxidation of DNH is rate-determining and of first order as to DNH, H2O2 and (possibly) NaOH (k1 = 1,5·10-3 s-1-1 M-2). The kinetic interpretation of the chemoluminescence-maxima confirmed this result. The light production occurred in a very fast secondary reaction step (k2 ≫ k1) following the oxidation of the hydrazid and with H2O2 participating. Diazochinone is assumed to be a primary oxidation product.
Interactions between some Psychodrugs and Flavins
Authors: Budini Rolando , Marinangeli Annamaria
Published: February 2015

Es wurde das Verhalten der Flavine gegenüber einiger Psychopharmaka untersucht. Die experimentellen Resultate lassen das Vorhandensein einer Wechselwirkung zwischen den zwei Molekülen annehmen. Die Ladungsübertragung spielt in diesem Prozeß eine wichtige Rolle. Eine Beziehung zwischen den berechneten ΔG0 und der pharmakologischen Wirkung der Droge wurde festgestellt.
Light Amplified Inhibition of Oxidative Phosphorylation by Chlorophyllins in Rat Liver Mitochondria
Authors: Lutz F. , Frimmer M.
Published: February 2015

Chlorophyllins inhibit oxidative phosphorylation in rat liver mitochondria, α-ketoglutarate oxidation is more sensitive than oxidizing succinate or β-hydroxybutyrate oxidation. When chlorophyllin is present, a sudden illumination of mitochondria incubated in the dark leads to a remarkable decrease of their O2-comsumption. In the absence of light the inhibition is diminished but not abolished.
Über das sterische Verhalten einer unterbrochenen Alpha-Helix / On the Steric Behaviour of an Interrupted Alpha-Helix
Authors: Jarosch R.
Published: February 2015

The revolutions and motions of the side-chains occuring on an interrupted Alpha-Helix after a change in the length of its hydrogen-bonds have been described with the help of an elastic moleculemodel.

Fig. 1 shows the directions of the revolutions (rotating arrows) after shortening of the hydrogenbonds in the case of the same (a, b, c, d) and different coiling-sense (e, f, g) of the two helical segments fixed at definite points (indicated by tongs). After elongation of the hydrogen-bonds all arrows point to the opposite directions. In the case of fig. 1 g and longer helices a drift in the surroundings may appear which is always directed to the cleft between the helices (arrows). The straight arrows indicate the shifting-tendency in the surroundings caused by the wave-propagation of the rotating helix.

The side-chains between adjacent areas of the helices move towards each other in the cleft near the nonhelical region (compare e. g. the side-chains 5 and 16 in figs. 2 a and 2 b). Moreover extreme changes in the position of certain side-chains occur in the interhelical segment of the polypeptide-chain (13 in figs. 2 b and 4 b, 12 in fig. 3 b). The amide-groups of the interhelical segment become unstable if the interhelical segment contains more than 3-4 dissociated hydrogen-bonds. In this case the changes in the positions of its side-chains (e. g. 13, 14, 15 in figs. 5 b and 6 b) are determined and occur strongly only when the interhelical segment is fixed in its middle (e. g. by 15 in fig. 6 a).

The possible importance of the described movements for the conformational changes of globular proteins is discussed.
Die Beziehungen zwischen Lipochinonsynthese und Plastoglobulibildung in den Chloroplasten von Ficus elastica Roxb. / The Correlation between Lipoquinone Accumulation and Plastiglobuli Formation in the Chloroplasts of Ficus elastica Roxb.
Authors: Lichtenthaler H. K. , Weinert H.
Published: February 2015

The structure of plastids, as well as size and frequency of the osmiophilic plastoglobuli were studied from the development of Ficus leaves until the degeneration of older leaves and compared with the accumulation of excess plastid-quinones.

1. The plastids on the young, light green Ficus leaves still rolled up in the buds already contain thylakoids. Prolamellar bodies and small plastoglobuli are, however, still present. Few days after leaf-unfolding the prolamellar bodies are used up in thylakoid formation; the number of plastoglobuli is reduced concurrently.

2. Thereafter size and frequency of the osmiophilic plastoglobuli increase with the age of Ficus chloroplasts. In several-year-old green Ficus leaves large plastoglobuli up to 3,5 μ diameter with the greatest frequency at 0,5 μ diameter can be found.

During chloroplast degeneration in senescent leaves both thylakoids and plastidstroma are dissolved progressively. The plastoglobuli remain. Their size still increases during chlorophyll breakdown. In the final yellow tob rown stage of Ficus leaves the plastids predominantly contain some larger plastoglobuli up to 7 μ arising by fusion of smaller ones.

3. The accumulation of excess plastidquinones - mainly α-tocopherol and plastohydroquinone 45 - proceeds concurrently to the formation and enlargement of the plastoglobuli. It is shown that the excess plastidquinones of Ficus chloroplasts are deposited in the osmiophilic plastoglobuli whose size thus increases. The isolated plastoglobuli predominantly contain α-tocopherol and plastohydroquinone 45, in lower concentrations also plastoquinone 45, α-tocoquinone, and vitamin K1, traces of carotenoids, but no chlorophylls.

4. During chlorophyll and thylakoid breakdown those lamellar lipids (carotenoids, plastidquinones) not decomposed are deposited together with the newly formed plastidquinones in the osmiophilic plastoglobuli. Plastoglobuli of degenerating chloroplasts thus contain more carotenoids than plastoglobuli from fully functional chloroplasts of green Ficus leaves.
Morpholines — (II)
Authors: Chatterjee Basanta G. , Lahiri S. K. , Abdulla Riaz F.
Published: February 2015

The new route to the synthesis of 3-oxo-1,4-oxazines 1 has been extended. N-aryl-N-chloroacetyl-m-nitro-phenacyl amines afford either only oxazine, or beta-lactam or both depending on the nature of the N-aryl substituent. A set of rules indicates from which precursors beta-lactam, as against morpholine formation, may be expected.
Über die Biogenese von Aromastoffen bei Pflanzen und Früchten. XI. Mitt.: Einbau von 14C-Leucin und -Valin in Bananenaromastoffe
Authors: Tressl R. , Emberger R. , Drawert F. , Heimann W.
Published: February 2015

Von den ca. 80 im Bananenaroma von uns gefundenen Estern weisen ca. 40 Methylverzweigungen auf. Diese werden strukturell von Leucin und Valin abgeleitet, was durch Zufuhr von 14C-mar-kiertem Leucin und Valin bei Bananenscheibchen nachgewiesen werden konnte.
Spaltungsreaktionen an perfluorierten Anhydriden
Authors: Roesky Herbert W. , Giere H. H.
Published: February 2015

Die Darstellung von

aus CH3N(Si(CH3)3)2 und P2O3F4 wird be-schrieben. Durch Spaltung von F2S2O5 mit CH3N(Si(CH3)3)2 und (CH3)3SiN=C=NSi(CH3)3 entstehen FSO2- NCH3-Si(CH3)3 und FSO2N = C = NSi(CH3)3. CF3SO2OSO2CF3 reagiert mit

(CH3)3SiN = C = NSi(CH3)3, (CH3)3SiOSi(CH3)3 und

zum CF3SO2N= C = NSi(CH3)3,

CF3SO2OSi (CH3)3 und

. CF3SO2NH2 setzt sich mit (CH3)3SiCl in Gegenwart

von (C2H5)3N zum

um. Mit dem Salz NaOCNC (CF3) 2 reagiert CF3SO2OSO2CF3 zum CF3SO2OCNC (CF3) 2. Bei sämtlichen Reaktionen wird die S - O - S- oder P - O - P-Bindung sehr leicht gespalten. Die neuen Verbindungen sind farblose Flüssigkeiten oder Festkörper. Die IR-, 1H- und 19F-KMR-Spektren werden mitgeteilt.
Polarographic Behaviour of Transition Metal Nitrosyl Complexes in Nonaqueous Media. IV. Cyclopentadienylnitrosylnickel
Authors: Paliani G.
Published: February 2015

The polarographic reduction of C5H5NiNO in DMF and ACN has been investigated. The first step of reduction involves an irreversible transfer of one electron to form an instable radical anion. On the basis of polarographic, voltammetric and coulometric measurements an overall mechanism is suggested.
Change in Sedimentation Profile of Protein Synthesizing Particles Observed After Protein Synthesis
Authors: Herrlich Peter , Schweiger Manfred , Wieber Irmgard , Lang Norbert
Published: February 2015

Protein synthesizing particles from rat liver sedimented more slowly after incubation under protein synthesis conditions. This change paralleled the degree of leucine incorporation which is stimulated by added RNA. Both effects seemed to be specific.
Low Temperature Reactions in Chloroplasts
Authors: Brody Seymour Steven
Published: February 2015

Some photoreactions of photosynthetic materials (corn chloroplasts, spinach chloroplasts and subchloroplast particles rich in System II) are examined at 77°K. The fluorescence yield of chlorophyll is observed to decrease reversibly upon irradiation at 77°K. The presence of ferricyanide in the chloroplast preparations increases the rate of decline of fluorescence yield while the presence of benzylviologen and phenazine methosulfate inhibits the decline of fluorescence yield. Extracts of Ricinus communis leaf (castor bean) also inhibits the decline of fluorescence yield. Data is given showing the effect of linolenic acid, extracts of Ricinus leaf, ferricyanide, benzylviologen and phenazine methosulfate on the ratio of fluorescence intensities at 725 and 700 nm.
Quarternäre Diimidazole und Dibenzimidazole
Authors: Röchling H.
Published: February 2015

Synthese und herbizide Eigenschaften einiger quarternärer Imidazole und Benzimidazole werden beschrieben.
Hemmstoffe der Photosynthese VI
Authors: Büchel K. H.
Published: February 2015

Die Darstellung einer Reihe von Benzimidazolen, die in 2-Stellung durch Gruppen wie - CHCl2, - CCl3, - CFCl2, -S-R, -SOR, -SO2R sowie -CO2R und - CONR1R2 substituiert sind, wird beschrieben. Einige Reaktionen sowie biologische Eigenschaften der Verbindungen werden diskutiert.
Hemmstoffe der Photosynthese VII
Authors: Röchling H. , Frasca Edith , Büchel K. H.
Published: February 2015

Die Umsetzung von Benzimidazolonen mit Isocyanaten und mit Carbamoylchloriden führt zu N-Carbamoyl-Derivaten. Die Darstellung und Isolierung von zwei isomeren Tetrachlor-benzimidazolonen wird beschrieben. Ausgehend von Tetrachlorbenzimidazolonen erhält man Pentachlor- und Hexachlor-benzimidazol.

Einige Substitutions- und Quaternisierungs-Reaktionen am Pentachlorbenzimidazol werden durchgeführt.
Über die Koordinations-Isomerie der Kobalt-methyl-Derivate der Cobyrsäure und der Cobinamid-monocarbonsäuren
Authors: Friedrich Wilhelm , Messerschmidt Reinhard
Published: February 2015

Kobalt-methyl-cobyrsäure sowie Kobalt-methyl-cobinamidmonocarbonsäuren lassen sich partialsynthetisch in zwei diastereoisomeren Formen darstellen. Das Synthesegut enthält ca. 10% Isomer a (hier ist die CH3-Gruppe „unten“ gebunden) und ca. 90% Isomer b (CH3-Gruppe „oben“) im Falle der Cobyrsäure bzw. ca. 22% Isomer a und ca. 78% Isomer b im Falle der Cobinamid-monocarbonsäuren.

Durch Belichtung bei 20°C bzw. Erwärmung auf 80°C, vor allem in CO-Atmosphäre, werden die Kobalt-methyl-cobyrsäuren a und b isomerisiert unter Bildung von Gemischen aus Isomeren a und b. Isomerisierung von Kobalt-methyl-cobyrsäure a führt zu einem Gleichgewicht, welches etwa der Zusammensetzung des Synthesegutes entspricht. Die CH3-Gruppe kann auch auf Aquocobalamin übertragen werden unter Bildung von Kobalt-methyl-cobalamin; auch diese Reaktion wird durch CO beschleunigt.

Die Katalyse der Isomerisierung bzw. Methylübertagung durch CO dürfte darauf beruhen, daß dieses Gas die im Medium stets in kleinen Mengen vorhandenen Diaquo-corrinoide reduziert unter gleichzeitigem Verbrauch von restlichem Sauerstoff. Homolyse bzw. Heterolyse der Kobalt-Kohlenstoff-Bindung durch Licht bzw. Wärme führt ebenfalls zu reduzierten Corrinoiden - neben Methylradikalen bzw. Methylkationen. Reagieren die letzteren mit fremden reduzierten Corrinoidmolekülen bzw. mit der fremden Seite der eigenen Moleküle, dann ergibt sich eine Isomerisierung bzw. Methylübertragung.
Metall-Bor-Verbindungen X / Metal Boron Compounds Xl
Authors: Schmid Günter , Weber Lothar
Published: February 2015

Bis (dimethylamino) -boronhalides react with dibenzonitrile palladium-dichloride (C6H5CN) 2PdCl2 in a different manner. Bis (dimethylamino) -boronchloride forms, just like bis (dimethylamino) methylborane complexes of the type Cl2Pd [ (CH3) 2N] 2BX (X = Cl, CH3). On the contrary the analogous bromo- and iodoboranes react with coordinated benzonitrile and form the diborylamine palladium complexes C6-C(X2) -N{B[N(CH3)2]2}2PdX (X = Br, J) which probably are dimeric. The B -N-groups presumably act as π-ligands.
II. Verteilung von 14C in Organen und Leberproteinen bei Ratten nach Applikation von 14C-Trichlorphon
Authors: Dedek Wolfgang , Lohs Karlheinz
Published: February 2015

14C -CH3O-Trichlorphon wurde i. v. und i. p. an Ratten appliziert und 14C in Organen und Leberproteinen bestimmt. Die Hauptmenge wurde in Leber als nicht extrahierbarer 14C gefunden. Die spezifische Aktivität des 14C bleibt in den mit Ammonsulfat gefällten Globulinen und Albuminen der Leber auch nach mehrfacher Umfällung konstant, so daß 14C als chemisch fest am Protein gebunden anzusehen ist. Wahrscheinlich finden Alkylierungsreaktionen nicht nur an niedermolekularen Peptiden, z. B. Glutathion, sondern auch an Proteinen statt. Die Konsequenzen dieser Untersuchungen werden diskutiert.
Inhibition of RNA Synthesis by α-Amanitin in Vivo
Authors: Niessing J. , Schnieders B. , Kunz W. , Seifart K. H. , Sekeris C. E.
Published: February 2015

Injection of α-amanitin inhibits both the synthesis of ribosomal and DNA-like RNA as measured by the incorporation of radioactively labelled orotic acid and ortho-phosphate into RNA extracted by phenol and subsequently fractionated by density gradient centrifugation and MAK column chromatography.
Quantitative Messung der Singulett- und Triplett-Absorptions-Spektren von Phäophytin a und b / Pheophytin-a and Pheophytin-b; Quantitative Absorption Spectra of the Singuletand Triplet-State
Authors: Zanker Valentin , Rudolph Ernst , Prell Gerhart
Published: February 2015

Quantitative singlet absorption spectra dependent on solvent, temperature, and concentration are shown. The bands observed in the visible and UV region are assigned to 3 π → π*-electron transfers.

Measurements at different acidities showed that the pheophytin molecule can be present in 3 prototropic forms; as a base, a mono- or a divalent cation.

In polar solvents of concentrations >10-4 M dimerization occurred. Larger clusters were formed in non-polar solvents at concentrations <10-4 Μ and at temperatures below ca. 200 °K.

The quantitative triplet (T) -absorption spectra for pheophytin a and b are also reported: the longest wavelength T-T-band is expected in the region 5000-8000 cm-1. The relaxation times and quantum yields of triplet formation are given; simple first order kinetics were found to fit the decay curves.
On a new inhibitor of photosynthetic electron-transport in isolated chloroplasts
Authors: Trebst A. , Harth E. , Draber W.
Published: February 2015

A halogenated benzoquinone has been found to inhibit the photosynthetic electron transport system in isolated chloroplasts. 2·10-6ᴍ of dibromo-thymoquinone inhibit the Hill- reaction with NADP, methylviologen or anthraquinone to 100%, but do not effect the photoreduction of NADP at the expense of an artificial electron donor. The Hill - reaction with ferricyanide is inhibited even at the high concentration of 2·10-5ᴍ of dibromo-thymoquinone to only 60%. The remaining reduction in the presence of the inhibitor reflects the rate of ferricyanide reduction by photosystem II. It is concluded that the inhibition of electron transport by the quinone occurs between photosystem I and II and close to or at the functional site of plastoquinone.
Immunologische Studien am Omentum V
Authors: Krüsmann W. F. , Kasemir H. , Ax W. , Fischer H.
Published: February 2015

Neonatally thymectomized mice show a markedly reduced mesothelial proliferation following an antigenic stimulus. As thymectomy causes a drastic reduction of circulating lymphocytes, lymphopenia may be the cause of the reduced mitotic rate of mesothelial cells. In order to prove this hypothesis, lymphopenia was caused by a) drainage of the thoracic duct and b) by injection of anti-thymocyte serum. In both types of experiments a drastic reduction of mesothelial proliferation was observed showing good correlation with the degree of lymphopenia. These results indicate that lymphocytes of thymic origin release mitosis promoting factors and thereby contribute to an immune response.
Spektroskopische Untersuchungen in der Festkörperchemie / Spectroscopic Research in Solid-State Chemistry
Authors: Burkert P. K. , Fritz H. P. , Stefaniak G.
Published: February 2015

The introduction of magnesium atoms into Li3N lattice yields 13 NMR signals for 7Li which is the greatest number of lines ever measured in a wide line NMR spectrum for I= 3/2. The comparison with theoretical first order quadrupole spectra allowed the observation of an additional satellite system and the quantitative calculation of the changes of the asymmetry parameters. It was found, that all changes in the Li3N spectrum on introduction of magnesium atoms occur in the range of the lithium satellite lines, which belong to weaker bound lithium atoms outside those lattice planes containing the nitrogen atoms.
Untersuchungen der kernmagnetischen Resonanz von Phosphor-Verbindungen XXI
Authors: Heckmann Gernot , Fluck Ekkehard
Published: February 2015

Die Konzentrations-Abhängigkeit der 31P-Kernresonanzlinien des Phosphortribromids und des weißen Phosphors im System P4-PBr3 ist beschrieben. Die Verschiebung der Resonanz von PBr3 mit zunehmender P4-Konzentration nach höherem Magnetfeld wird durch die Existenz eines P4 · PBr3-Komplexes erklärt. Aus diesen chemischen Verschiebungen, bei denen die Dispersionswechselwirkung zwischen P4 und PBr3 berücksichtigt wurde, ergab sich bei einer Temperatur von (30,0±0,5) °C eine Assoziationskonstante von Kg=(0,031 ± 0,002) kg/Mol bzw. in Molenbrucheinheiten von Km=0,25±0,02. Für die chemische Verschiebung der Resonanz des PBr3 im Komplex relativ zu reinem Phosphortribromid findet man (42 ± 2) ppm.
Oxygen Effect in γ-irradiated DNA
Authors: Lücke-Huhle Christine , Braun Arnim , Hagen Ulrich
Published: February 2015

Purified, dry DNA and dry nucleoprotein were irradiated with 60Co-γ-rays under a nitrogen or oxygen atmosphere. The DNA was isolated from the irradiated nucleoprotein. In the DNA the following radiation induced changes were investigated: Double strand breaks, single strand breaks and crosslinks between the DNA molecules. An oxygen effect (OER > 1) was found for all of these events except for crosslinks in irradiated DNA. In the nucleoprotein, the oxygen effect is more marked than in pure DNA.
Der Einfluß von partiellen Hepatektomien auf die Hepatomrate nach Diäthylnitrosamin-Gaben
Authors: Grünthal D. , Hellenbroich D. O. , Sänger P. , Maass H.
Published: February 2015

Rats were hepatectomised and subsequently diethylnitrosamine was applied orally (2 mg DENA/kg/d). Compared with a non-treated control group the mean survival time was lowered from 225 to 158 days. In a second experiment repeated hepatectomies were performed. All these rats were killed after 40 weeks and after a total DENA dose of 351 mg/kg. By histological examination of the livers a higher rate of hepatomas was found in the hepatectomised group.

Thus the proliferating processes during liver regeneration seem to favour the hepatocarcinogenesis under DENA treatment.
Substituenteneffekte bei triphenylmethanfarbstoffen II
Authors: Broser Waldemar , Fleischhauer Heinrich
Published: February 2015

A series of buffers, for methanol p.A. (water content 0,05%), were prepared and measured potentiometrically. The series, covering a pH*-range of 2.4-12.4, consists of ten buffers which are tabulated in steps of 0.2 pH*-units
Das Bürzeldrüsensekret der Saatkrähe (Corvus frugilegus) / The uropygial gland fat of the rook (Corvus frugilegus)
Authors: Jacob Jürgen , Glaser Armin
Published: February 2015

The uropygial (preen) gland fat of the rook (Corvus frugilegus) is a mixture of ester waxes of which 2-methyl-substituted fatty acids with a chain length of C16-C22 are shown to be the acidic components.

The alcoholic components are n-alkanols with a chain length of C6-C12.

As to the 32nd order of the natural system the uropygial gland fat seems to differ in the single families already if compared with that of the common sparrow
Effect of proteolytic and lipolytic enzymes on the electron transport particle fraction of rhodospirillum rubrum
Authors: Boll M.
Published: February 2015

Digestion of the electron transport particle fraction of Rhodospirillum rubrum with the proteases chymotrypsin, trypsin, subtilisin and pronase resulted in a release of protein from the membranal system. The solubilization was, however, limited to only 15 - 18 percent of the total protein, being the same with each of the four proteases. The enzymes catalyzing electron transfer which are located on these particles were not solubilized by the proteolytic digestion but were found to become differently inactivated already with low protease concentrations. The proteolytic attack revealed differences in the specificity of proteolysis between chymotrypsin and the other proteases
Nematische Systeme II
Authors: Pohl Ludwig , Steinsträsser Ralf
Published: February 2015

The composition of binary and ternary eutectics of homologous, nematic p,p′-disubstituted benzylideneanilines, the specifically staggered arrangement of molecules in crystals of anisaldazine-. ρ,ρ'-azodiphenetole and p-azoxyanisole, and NMR-investigations in p,p′-di-n-hexyloxyazoxybenzene lead to the suggestion that, under certain circumstances, nematic liquid crystals can enter into a short range order consisting not of individual molecules but of molecular strands of different lengths, each built up of three individual molecular chains having probably a head-to-tail sequence and turned by 180° with respect to each other. We designate such a liquid crystalline state of order as a nematic secondary structure.
Photoreactions and Complex Formation of Retinal Monolayers at a Water-Air Interface
Authors: Brockman R. E. , Brody S. S.
Published: February 2015

Monomolecular films of cis or trans isomers of retinal were spread at a water-air interface. Isotherms were measured. The area per molecule (extrapolated to zero pressure) for 9-cis retinal, all-trans retinal, and 13-cis retinal on 10-2 ᴍ phosphate buffer at pH 6 is 56 Å2, 54 Å2 and 45 Å2, respectively. Complexation was observed between 9-cis retinal (9-cis) and β-mercaptoethylamine (MEA) dissolved in the subphase; however, ʟ-lysine does not appear to form a complex wth 9-cis retinal. The area per molecule of the complex as a function of subphase concentration (MEA) was determined. The area per molecule for 9-cis is decreased to 49 Å2 after irradiation with blue light. Irradiation does not appear to break the complex between 9-cis and MEA. The lower limit for the quantum yield for photoisomerization of 9-cis, on phosphate buffer, is 0.06. When 9-cis is complexed with MEA (5 × 10-6 ᴍ) the quantum yield for photoisomerization is lowered, e. g. at 5 × 10-6 ᴍ MEA the yield is 0.03.
The Sparing Effect of UV- and X-ray-dose-fractionation in Starved Diploid Yeast
Authors: Kiefer Jürgen
Published: February 2015

The sparing effect of UV- and X-ray dose fractionation and the influence of pre-exposure starvation were investigated in diploid yeast, Saccharomyces cerevisiae. A sparing effect could be demonstrated in starved cells if they were incubated in fresh nutrient medium during the fractionation interval. The time necessary for complete recovery, however, was greatly increased as compared to unstarved stationary phase cells. The possible role of cell progression and partial synchronization is discussed.
Interactions of Chlorophyll Monolayers with Electron Donors and Acceptors
Authors: Brody Seymour Steven
Published: February 2015

Photoreactions and complexation reactions between monolayers of chloroplyll a, at a water-air interface, and various electron donors and acceptor in a Wilhelmy film balance.

When phenazine methosulfate (PMS), ascorbate, benzyl viologen (BV), or dehydroascorbic acid are present in the aqueous subphase, the area/molecule increases with substrate concentration in accordance with a Langmuir- type adsorption isotherm. The increase in area is attributed to a reorientation of chlorophyll upon complex formation. The surface potentials and areas/molecule (at zero pressure) are 350 mV and 179 Å2 for PMS + ascorbate in the subphase, 300 mV and 175 Å2 for PMS, 310 mV and 146 Å2 for BV, 310 mV and 156 Å2 for ascorbate, 230 mV and 146 Å2 for dehydroascorbic acid. The equilibrium constants are 170 × 103 ᴍ-1 for PMS + ascorbate, 64 × 103 ᴍ-1 for PMS, 41 × 103 ᴍ-1 for BV, and 3.9 × 103 ᴍ-1 for ascorbate. Formation of a complex decreases the slope of the isotherm, thereby giving the film a more liquid nature. Chlorophyll does not complex with oxidized PMS.

Illumination of the chlorophyll · BV complex in a nitrogen atmosphere results in an oxidation of chlorophyll; the photoproduct (probably Chl⊕ · BV⊖) has a larger area/molecule, of 165 Å2, and a lower surface potential, of 280 mV. Illumination of the chlorophyll · ascorbate complex or the chlorophyll · PMS · ascorbate complex results in a reduction of chlorophyll. The photoproduct of the former reaction (probably Chl⊖ · -oxidized ascorbate) has a larger area/molecule, of 169 Å2, and a lower surface potential, of 290 mV. The photoproduct of the latter reaction (probably Chl⊖ · PMS · oxidized ascorbate) has a larger area/molecule, of 211 Å2, and a larger surface potential, of 380 mV. No evidence is observed for a photoreaction with the Chl · PMS complex or the Chl · dehydroascorbic acid complex. A value of 0.03 is determined as a lower limit for the quantum yield of these reactions. In all cases the absorption spectrum of the chlorophyll recovered from surface after irradiation shows no significant differences from the control.
Preparation and 31P Chemical Shifts of Some Quaternary Phosphonium Salts
Authors: Grim Samuel O. , Davidoff Edward F. , Marks Tobin J.
Published: February 2015

This paper reports the synthesis, analytical data, melting points, and phosphorus chemical shifts of over seventy quaternary phosphonium salts. Most of these data have not been reported.
Polarographische Untersuchung des Systems Folsäure — Dihydrofolsäure — Tetrahydrofolsäure / Polarographic Examination of the System Folic Acid — Dihydrofolic Acid — Tetrahydrofolic Acid
Authors: Kretzschmar Klaus , Jaenicke Walther
Published: February 2015

7,8-Dihydrofolic acid and tetrahydrofolic acid were prepared from folic acid. The three compounds were examined by different polarographic methods. The diffusion coefficient of folic acid was determined independently.

Folic acid is reduced via a reversible 2-electron step, an irreversible transformation of the primary product, giving 7,8-dihydrofolic acid. The reduction is continued by two further 2-electron steps with an intermediate chemical reaction (the cleavage of the side chain). The redox potentials are measured and the mechanism of the reaction is discussed.