Volume 25, Issue 1

Einige physikalische Eigenschaften des Selenocarbohydrazids, wie Löslichkeit, hygroskopisches Verhalten und thermische Stabilität, wurden quantitativ bestimmt. Die Salze SeC (NH-NH 2 ) 2· 2 HBr, SeC(NH-NH 2 ) 2 ·2 HJ, SeC(NH-NH 2 ) 2 ·H 2 SO 4 und SeC(NH-NH 2 ) 2 ·H 3 PO 4 wurden erstmals dargestellt und charakterisiert.

Durch Umsetzung von Selenocarbohydrazid mit Cyansäure und Thiocyansäure wurden 1-Carbamoyl-selenocarbohydrazid, NH 2 -CO-NH-NH-CSe-NH-NH 2 , und 1-Thiocarbamoyl-seleno-carbohydrazid, NH 2 -CS-NH-NH-CSe-NH-NH 2 , durch Reaktion des Sulfates von Selenocarbohydrazid mit Ammoniumthiocyanat das 1.5-Bis-thiocarbamoyl-selenocarbohydrazid, NH 2 -CS-NH-NH-CSe-NH-NH-CS-NH 2 , erstmals dargestellt. 1-Carbamoyl-selenocarbo-hydrazid und 1-Thiocarbamoyl-selenocarbohydrazid reagieren mit Aldehyden unter Hydrazonbildung. Zur weiteren Charakterisierung wurden alle Verbindungen IR-spektroskopisch und röntgenographisch untersucht, wobei gezeigt werden konnte, daß sie ganz analog den entsprechenden Thiocarbohydrazid-Derivaten aufgebaut sind.

Es wird über eine neue Synthese von Natriumdodecahydro-dodecaborat berichtet. Die Identifizierung des B 12 H 12 -Ions erfolgte über 11 B-Kernresonanzspektren, die Analyse durch Fällung als Tetraphenylarsoniumsalz. Maßanalytische Analysenmethoden werden diskutiert.

Durch Umsetzung von 2.3-disubstituierten Äthanolaminen mit Brommethyl-dimethyl-äthoxy-silan wurden 6-gliedrige Ringe der Konstitution 3 hergestellt. Aufnahme und Auswertung der 100 MHz- 1 H-NMR-Spektren ergab Cyclohexane in der Sessel-Konformation mit äquatorialer Stellung der Alkylgruppen an Stickstoff und Kohlenstoff.

Es wird die Herstellung von neuen organischen Silicium-Benzophenon-Derivaten durch Umsetzung von Chlorsilanen mit 2-Hydroxy-4-methoxy-benzophenon beschrieben. Die UV-Absorption dieser neuen Verbindungen wird mit der von Benzophenon-Derivaten des Aluminiums und Phosphors verglichen.

Reactions of carboxylic acids in different stoichiometric ratios have been carried out under anhydrous conditions, the compounds of the type U (OEt) 4 (OOCR), U (OEt) 3 (OOCR) 2 U (OEt) 2 (OOCR) 3 and U (OEt) (OOCR) 4 (where R is CH 3 , C 2 H 5 , C 3 H 7 and C 6 H 5 ) have been isolated. Lactic acid yielded the compounds of the type U (OEt) 3 (C 3 H 4 O 3 ), U (OEt) (C 3 H 4 O 3 ) 2 , U 2 (C 3 H 4 O 3 ) 5 and U (C 3 H 4 O 3 ) (C 3 H 5 O 3 ). Determination of molecular weight of some of the soluble derivatives of benzoic acid, suggest them to be dimeric in boiling benzene.

Stepwise mixed ligand complex formation is observed in the systems containing metal ion, iminodiacetic acid (IMDA) as primary ligand and one of the diamines, such as ethylenediamine (en), 1,2-propanediamine (1,2-pn) and 1,3-propanediamine (1,3-pn) as secondary ligands. Potentionmetric titrations indicate the formation of ternary complexes having a 1:1:1 molar ratio of metal ion to iminodiacetic acid to the secondary ligand. Initially, metal-IMDA (1:1) complex is formed in the lower buffer region prior to the formation of the ternary complex and the addition of the secondary ligand takes place only after the combination with the primary ligand is complete. Formation constants (log K MAB ) of the ternary complexes have been calculated and the probable reaction mechanism is suggested. The order of stability in terms of metal ion has been found to be Cu (II) > Ni (II) >Zn (II) >Cd (II) and in terms of secondary ligand as 1,2-pn>en>1,3-pn.

The potentiometric studies of the systems, copper (II)-oxalic acid and one of the diamines, o-phenylenediamine(phenen), ethylenediamine(en) and 1,2-diaminopropane(pn) have been carried out. These studies show the formation of mixed ligand complexes in which all the three species are present in the ratio of 1:1:1.

Copper (I) chloride has been used for the potentiometric determination of sulphur compounds, namely, n-dodecane-thiol, toluene-α-thiol, thiophenol, monothioglycerol, 2-mercaptoethanol and β-mercaptopropionic, thioglycollic, thiobenzoic and thiosalicylic acids. The determinations are possible even in the presence of their corresponding oxygen derivatives and results within an accuracy of ± 0.4% have been obtained.

Schiff base derivatives of niobium and tantalum of the types, M(OPr i ) 3 SB, M(OPr i )(SB) 2 and M(SB) 2 (SBH) have been synthesized by the reactions of the metal isopropoxides with the Schiff bases in 1:1, 1:2 and 1:3 molar ratios (where M=Nb or Ta, SBH ⊖ and SB 2⊖ represent the corresponding anions of the Schiff bases). Except the triisopropoxy acetylacetone-2-hydroxy-alkylimine derivatives of these metals which are distillable, all the remaining complexes decompose when an attempt is made to distil them. The triisopropoxy mono - Schiff base and the tris - Schiff base derivatives of these metals are essentially monomeric in boiling benzene and probably possess hexa- and octa-coordinated metal atoms, while the monoisopropoxy bis-Schiff base complexes show slight tendency of polymerization.

The absorption spectra of 3′-hydroxy 1-methyl 2-quinolinium iodide, 4′-hydroxy styryl 1-methyl 2-quinolinium iodide, 3′: 4′-hydroxy 3′-methoxy styryl 1-methyl 2-quinolinium iodide in different solvents have been studied in the region 200 mμ -1000 mμ. Four bands have been assigned to different intramolecular transitions.

Anisol, Phenetol und Propylphenyläther geben im Plasma Alkylphenole und Phenol. Die Abhängigkeit der Gesamtausbeute und der Zusammensetzung der Produktgemische von den Versuchsparametern sowie des Reaktionsmechanismus wird diskutiert.

The spectral characteristics of prodigiosin in the visual range and the changes occurring in them through different concentration of the substance, polarity of solvent, and temperature have been studied. The conclusion has been reached that these changes are due to the existence of two forms of the pigment: monomeric - with a maximum at 460 mµ, and dimeric - with a maximum at 530 mµ. It is assumed that in certain conditions there may exist a trimeric form of the pigment. Data are being adduced in support of that assumption.

Aus Arthonia impolita (EHRH.) BORR. wird das neue Depsid Arthoniasäure isoliert und als 4-O-Desmethyl-2′-O-methyl-microphyllinsäure (1) strukturell aufgeklärt.

The uropygial (preen) gland fat of the puffin (fratercula arctica) is mainly a mixture of waxes (77%) and triglycerides (23%). The isolated triglycerides which are the main part of the fat tissue of the gland differ only little from the depot fat which was investigated simultaneously. After separation into groups of equal carbon number by preparative GLC the waxes were shown to be a complex mixture of esters between straight-chain, even-numbered alcohols (chain-length C 8 , C 10 , C 12 , C 14 and C 16 ) and octanoic, decanoic and dodecanoic acid.

The infrared and Raman spectra of triosereductone in polycrystalline state as well as its 1 H-n.m.r. spectrum in DMSO-solution support a structure with two five-membered chelate rings.

Addition of EDTA * to ribosomal preparations followed by gelfiltration on agarose-columns, causes separation of ribosomal proteins accounting for the pink colour of ribosomes. This chromoprotein contains 20% iron. It recombines with the colourless subribosomal nucleoproteid-particle from which it had been released, during incubation in a ribosome-stable buffer lacking EDTA.

After preparation of a coloured protein component containing iron from rat liver ribosomes 1 this fraction was submitted to detailed analysis by means of polyacrylamide gel electrophoresis. Thus it may be separated into one main and two secondary bands, which do not contain RNA detectable by methylene blue staining. The ferric content of all bands can be demonstrated by staining with 2,4-dinitroso-1,3-naphthalenediol 2 . These bands are to be found in the large ribosomal subunits as well as in the small one in qualitative conformity, they differ, however, in their quantitative relations to each other depending on origin. LiCl-extraction as described for the preparation of ribosomal proteins causes dissociation of the chromoproteid fraction into six bands possessing lower molecular weights each than the original bands. The chromoproteids, localized in the large ribosomal subunits on the one hand and in the small subunits on the other hand were prepared differentiatedly by gel filtration. Results show the chromoproteid represented in the 57-S-subunit on a bigger scale than the nucleoproteid part, on the contrary, the 29-S-subunit is constructed of RNA-containing material preferably.

Glasmikropipetten mit Spitzendurchmessern von 2,5 μm, d. h. eine Größenordnung größer als die gewöhnlichen elektrophysiologischen Elektroden, werden dazu benutzt, in 0,1 ᴍ KCl die Potential-Übertragungseigenschaften (PTP) für Sinus- und Stufenpotential von Elektroden zu vergleichen, die gefüllt sind a) mit 0,1 ᴍ KCl (EM) und b) mit Metall (MM). Die PTP sind abhängig von drei Elektrodenparametern, R s , R, C und von der Verstärkerstreukapazität C a . Die Parameter werden durch Messung des bei Anlegen einer Dreieckspannung entstehenden Strom-Zeitverlaufs bestimmt, Fig. 3. R s , der Lösungs-Serienwiderstand, ist vor der Elektrodenspitze lokalisiert, Fig. 1, table 1. R s bestimmt zusammen mit C a die obere Grenzfrequenz der Messung, eqs. (11) und (12). Der Elektrodenwiderstand R (table 2) und die Elektrodenkapazität C sind bei EM kleiner als bei MM. Das führt - bei unkompensiertem C a - zu komplementären PTP von EM und MM: EM sind besser für Niederfrequenzmessungen (ω RC ≦ 1, d. h. 0 - 10 KHz oder lange Stufendauer t/RC ≧ 1), während MM - wegen größerem C - besser verwendbar sind zur Hochfrequenzmessung (ω RC ≧ 1, f ≧ 10 KHz oder kurze Stufendauer t/RC ≦ 1), Figs. 4 und 5. Der Spannungsmeßverstärker, Fig. 2, gestattet elektronische Kompensation von C a . Die resulierende Verbesserung der PTP beträgt zwei Größenordnungen, Figs. 4, 5 und 6. MM mit Ag/AgCl- oder Sb-Füllung können zur Messung von pCl bzw. pH in anorganischen Elektrolyten verwendet werden. Fig. 7. Die unvermeidlichen Probleme von MM (sehr kritisch für MM kleiner als die Modellelektroden) werden im Appendix behandelt.

In normal controls, the levels of hemoglobin concentration and hematocrit values remained almost unchanged throughout the experimentation period. Intraperitoneal administration of imidazole and benzimidazole affected rapid pharmacodynamic incidences which were not detected with cysteamine. Administration of imidazole did not induce detectable change in the level of hemoglobin concentration but slightly decreased the hematocrit value. Benzimidazole created slight depression in hemoglobin concentration and exerted no effect on hematocrit value. Cysteamine caused slight depression of both hemoglobin concentration and hematocrit value. Those changes were readily restorable with imidazole and benzimidazole while those with cysteamine lasted for more than three days. Irradiation caused progressive decrease in hemoglobin concentration and hematocrit values which continued till the death of the animals. A significant increase in the sedimentation rate of red blood cells was recorded. Irradiation of chemically protected animals caused initial decrease in hemoglobin concentration and hematocrit values which lasted till the fifths post-exposure day. Later, gradual restoration of normal levels of hematological values was recorded. Restoration was more rapid with benzimidazole than with imidazole, while cysteamine lied half way in its action. The increase in sedimentation rate of red blood cells was less pronounced and gradual restoration of the normal sedimentation rate was maintained during the post-irradiation time. It seems likely that the radioprotectants act on cellular and subcellular levels in the protected tissues but the actual role played by such compounds still awaits further investigation. Imidazole and benzimidazole proved to be effective radioprotectants of the hematopoietic tissue. Benzimidazole proved to exert the best radioprotective characters amongst the tested compounds in this concern.

Basierend auf der Detailstruktur der Thylakoidmembran wird ein allgemein gültiger molekularer Mechanismus für den Protonentransport über biologische Membranen vorgeschlagen. Es wird angenommen, daß aufgrund einer Redoxreaktion auf der Membranaußenseite eine Umpolarisierung innerhalb der Phospholipidschicht induziert wird, die zu einer Protonentranslokation führt. In diesem Pumpmodell wird die anisotrope protolytische Reaktion an einer amphoteren Phosphogruppe und einer an der Innenseite der Membran fixierten PO ⊝ -Gruppe bewerkstelligt. Die Umpolarisierung dieser Molekülgruppierung und ihrer Hydrathülle erfolgt durch die Einführung eines Dipols in einer Redoxreaktion, bei der ein Elektron über eine Distanz von ca. 20 -25 Å auf der Membranaußenseite transferiert wird.

14 C-Trichlorphon ( 14 CH 3 O-markiert) wurde mit Humanserum 3 h bei 37.5°C inkubiert. Das gefällte Protein wurde hydrolysiert und die Aminosäuren getrennt. Im Eluat sind mindestens 3 scharfe Maxima der 14 C-Aktivität vorhanden. Es wird angenommen, daß Methylierungs-Reaktionen an definierten Substraten einen wesentlichen Bestandteil der komplexen Wirkung toxischer Organophosphor-Verbindungen darstellen.

Using the device of Fig. 1 (this paper and 1. c. 3 ) efflux of Cl ⊖ across the plasma membrane of root cortex cells was found to increase with increasing external concentration of various salts. We conclude that non-specific (passive) plasma membrane permeability (!) to anions increases with increasing external concentration of salts. As a primary result passive efflux of anions, which is downhill in the electrical gradient, increases. Efflux of Rb ⊕ across the plasma membrane is only slightly stimulated by external KCl and is inhibited by Ca 2⊕ . The decrease in electrical potential with increasing external salt concentration is a consequence of the increase in passive plasma membrane permeability to anions. Interaction of salts with charged groups of the plasma membrane is not unlikely to be the reason for the increase of the permeability to anions and for the multiple hyperbolic influx isotherm observed at high external concentrations (1-100 mM). We want to emplasize that a multiple hyperbolic isotherm may be considered a feature of passive ion movement across a barrier of different charged groups.