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Institute
Exposite produce chemiluminescence when heated to 50 - 70 °C or treated with nucleophilic substances at room temperature. Initiation by Piperidine in Dimethylsulfoxide allows to determine 5 nmol of Phenyloxirane in 5 ml samples.
Phosphoenolpyruvate carboxykinase (PEPCK) from Phycomyces blakesleeanus was partially purified by protamine sulfate precipitation, ammoniumsulfate precipitation, and diethylamino ethyl cellulose (DEAE) treatment. This preparation was employed for the characterization of the enzyme. The Km values for phosphoenolpyruvate (PEP) and ADP were determined as 1.6 and 0.42 mᴍ. The nucleotid specifity was demonstrated for ADP exclusively. The use of sulfuryl reagents showed the presence of thiol groups sensitive against p-hydroxymercuribenzoate but not effected by N-ethylmaleimide.
The He(I) photoelectron spectra of the following molecules with S·̱·̱̱·̱·̱·̱̱·̱N multiple bonds ... are assigned by radical cation state comparison between the chemically related compounds as well as by MO models based on CNDO calculations. From the ionisation energies of the O=S=O/HN=S=O pair a parameter απSN can be deduced, which proves to be useful in the discussion of other SN compounds like R3C-N=S=O and RN=S=NR.
The reactions of diluted aqueous solutions of SO2 resp. HSO3-ions with MnO4-or Ce4+ ions in the pH range 1-4 produce chemiluminescence in the spectral region of 450-600 nm. Measurements of the time course of the light emission and their simulation on an analog computer led to a reaction scheme in which a recombination product of primarily formed HSO3 radicals -of a lifetime of about 1 second -appears as precursor of electronically excited SO2 molecules. The participation of singlet oxygen can be excluded because at least the reaction with Ce4+ ions proceeds also in the absence of oxygen.
Arsenhaltige Heterocyclen
(1978)
In the reaction of N,N'-bis-trimethylsilyl-dimethylurea with As[N(CH3)2]3 a four membered ring O = C(NCH3)2AsN(CH3)2 1 could be isolated. 1 was not obtained by cleavage of the Si-N-bonds with the corresponding chloride. In contrast CH3N[CONCH3Si(CH3)3]2 reacts with AsCb to yield the six-membered ring CH3N(CON-CH3)2ASCl 2. The four-membered ring which contains an arsenic-halogen bond seems to be unstable. In the adamantane-type compound, AS4(NCH3)6, one methylamine could be eliminated by CF3SO3H to give AS4(NCH3)5(OSO2CF3)2 3. 1H, 19F NMR as well as mass spectroscopy have been used in the characterization of the products obtained.
Über Reaktionen von 3-trifluormethylphenylsubstituierten silicium-und zinnorganischen Verbindungen
(1978)
Several routes were investigated for the preparation of 3-CF3C6H4N[Si(CH3)3]2 2 and 3-CF3C6H4N[Sn(CH3)3]2 3. The latter compound reacts with 3-CF3C6H4NCO to yield [3-CF3C6H4(CH3)3SnN]2CO 4. A substituted urea 5 is also formed from [(CH3)3Si]2NCH3 and 3-CF3C6H4NCO. 5 is used for the preparation of cyclic compounds, with S2Cl2 the ten-membered ring (3-CF3C6H4NCONCH3S2)2 6 is formed. 5 and HN(SO2Cl)2 yield the six-membered ring 3-CF3C6H4NCONCH3(SO2)2NH 7. SeOCl2 and 5 react under formation of a spiro compound (S-CF3C6H4NCONCH3)2Se 8. The compounds were characterized on the basis of mass and 19F NMR spectra.
N-Sulfonylsulfimide
(1978)
(CF3SO2NSO2)2 (1), a compound with a four-membered ring, was prepared from CF3SO2NSO and SO3. 1 as well as (FSO2NSO2)2 form 1:1 adducts with S4N4 , pyridine and pyridine carbonitrile-4 (2a-2f). By comparison with FSO2NCOS4N4 it was shown that a dipolar type of addition had occured. In contrast the reaction of 1 and (FSO2NSO2)2 with aromatic nitriles yields 1:2 cycloaddition products (3a-3g) which were characterized on the basis of mass spectra. The six-membered rings of 4a-4b which contain carbon, nitrogen and sulfur atoms were obtained from the reaction of isocyanates with (FSO2NSO2)2 or (CF3SO2NSO2)2. 4-BrC6H4NCO and SO3 react in a similar way to yield 5. The starting materials are extremely sensitive to moisture while most of the adducts can be handled in open air without decomposition.
Novel radical anions of trimethylstannyl substituted naphthalenes and their ESR spectra are reported. Both 119 Sn and 117 Sn coupling can be assigned unequivocally. The perturbation of π systems by R3X substituents of group IV b elements X = C, Si, Ge, Sn and Pb is discussed with respect to photoelectron ionization potentials, charge transfer excitations, half-wave reduction potentials and ESR spin distribution.
Das Cranium eines fossilen Hominiden des Formenkreises Homo sapiens sapiens wurde relativ-geologisch sowie absolut durch Radiokohlenstoff und Aminosäuren auf ungefähr 31 000 Jahre B.P. datiert. Andere absolute sowie relative Daten an Mollusken und Mammutzähnen in überlagernden jüngeren Straten datieren auf 18 000 — 21000 und 16 000 Jahren B.P. Geomorphologische und geophysikalische Datierungen stimmen somit gut überein. Er ist der älteste datierte und früheste Bewohner Zentraleuropas, der dem Homo sapiens sapiens angehört.