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71.
72.
73.
F. Asinger H. Offermanns D. Neuray P. Müller 《Monatshefte für Chemie / Chemical Monthly》1970,101(5):1295-1308
Zusammenfassung Propionaldehyd, n-Butyraldehyd und n-Valeraldehyd reagieren mit Äthylenimin und Schwefel in Gegenwart von Dimethylformamid oder wasserfr. K2CO3 zu Gemischen von 2-monoalkylierten 5,6-Dihydro-4H-1,4-thiazinen (2–4) und 2-monoalkylierten Thiazolidinen (6–8). Bei Einsatz von Acetaldehyd in diese Reaktion konnte nur 2-Methylthiazolidin (5) isoliert werden. Durch Kondensation von -Chloraldehyden mit Cysteaminnatrium erhält man die 2-Alkyl-5,6-dihydro-4H-1,4-thiazine (2,3) als alleinige Reaktionsprodukte.Die Umsetzung von2 und3 mit Ameisensäure führt zu Gemischen von N-Formylthiomorpholinen (9, 11) und N-Formyl-5,6-dihydro-1,4-thiazinen (10, 12), aus denen man entweder durch Hydrolyse mit verd. HCl (9,1113,14) oder besser durch Hydrierung und Hydrolyse mit Natriumboranat (9,11,10 und1213,14) die entsprechenden 2-monoalkylierten Thiomorpholine gewinnt. Unsubstituiertes Thiomorpholin (15) sowie13 und14 lassen sich in besseren Ausbeuten (42–70%) gewinnen, wenn man die durch Umsetzung der -Chloraldehyde mit Cysteaminnatrium erhaltenen 5,6-Dihydro-1,4-thiazine nicht isoliert, sondern direkt mit Natriumboranat behandelt.
Herrn Prof. Dr. phil. habil.R. Tschesche zum 65. Geburtstag gewidmet.
71. Mitt.:F. Asinger, H. Offermanns, K. H. Lim undD. Neuray, Mh. Chem. (im Druck).
Teil der DissertationP. Müller, Techn. Hochschule Aachen, 1968. 相似文献
Synthesis of thiomorpholine and 2-monoalkylated thiomorpholines via 5.6-Dihydro-1.4-thiazines (Joint action of elementary sulfur and gaseous ammonia upon ketones, LXXII)
Propionaldehyde, n-butyraldehyde and n-valeraldehyde react with ethylenimine in the presence of dimethylformamide or anhydrous K2CO3 to mixtures of 2-monoalkylated 5.6-dihydro-4H-1.4-thiazines (2–4) and 2-monoalkylated thiazolidines (6–8). When acetaldehyde is inserted in this reaction, solely 2-methyl-thiazolidine (5) could be isolated. By condensation of -chloroaldehydes with the sodium salt of cysteamine 2-alkyl-5.6-dihydro-4H-1.4-thiazines (2,3) are obtained as the only reaction products.Reaction of2 and3 with formic acid affords mixtures of N-formylthiomorpholines (9, 11) and N-formyl-5.6-dihydro-1.4-thiazines (10, 12), which yield either by hydrolysis with dilute HCl (9, 1113, 14) or better by hydrogenation and hydrolysis with NaBH4 (9, 11, 10, and1213, 14) the corresponding thiomorpholines. Unsubstituted thiomorpholine (15) as well as13 and14 are obtained in better yields (42–70%), if the 5.6-dihydro-1.4-thiazines, synthesized by reaction of -chloroaldehydes with the cysteamine-sodium salt, are not isolated, but directly hydrogenated with NaBH4.
Herrn Prof. Dr. phil. habil.R. Tschesche zum 65. Geburtstag gewidmet.
71. Mitt.:F. Asinger, H. Offermanns, K. H. Lim undD. Neuray, Mh. Chem. (im Druck).
Teil der DissertationP. Müller, Techn. Hochschule Aachen, 1968. 相似文献
74.
Summary Carbon disulphide reacts with bis(-mercaptopropylamine)nickel(II) by insertion into the Ni-N bond to yield a planar dithiocarbamate complex, in which the Ni-S bond is broken and a sulphydryl group is formed. 相似文献
75.
A large number of preparatively interesting compounds have become readily available by the simultaneous action of sulfur and ammonia or amines on ketones. Direct syntheses of Δ3-thiazolines, Δ3-imidazoline-5-thiones, 5,6-dihydro-4H-1,4-thiazines, and the 1,2,3,4,5,6-hexathiocane system from ketones, sulfur, and ammonia or amines, and further possibilities for the synthesis of these heterocyclic systems have been proposed. Other heterocycles containing N or N and S (thiazoles, thiophenes, thiazolidines, tetrahydrothiazolo[2,3-c]-1,4-thiazines, thiomorpholines, 4-amino-2H-imidazoles, etc.) are readily obtainable by further reactions of these compounds. Hydrolysis of the Δ3-thiazolines yields α-mercapto ketones, which are the starting materials for other syntheses. Most of the syntheses described proceed at room temperature and at normal pressure. 相似文献
76.
Peroxisomes (PO) are a heterogeneous population of cell organelles which in mammals are most abundant in liver and kidney. Commonly, differential and density gradient centrifugation are used for their isolation which, however, give only rise to the so-called "heavy" PO with a buoyant density of 1.22-1.24 g/cm(3). Subpopulations other than the heavy PO which are also present in both of these tissues have escaped adequate purification because of their sedimentation characteristics which are close to those of other major organelles, in particular microsomes. Since the purification of these subpopulations has become an essential task in view of the putative importance of peroxisomal subpopulations in the biogenesis of this organelle, alternatives to density gradient centrifugation are required. Recently, we have introduced such a novel approach, named immune free flow electrophoresis (IFFE). IFFE combines the advantages of eletrophoretic separation with the high selectivity of an immune reaction. It makes use of the fact that the electrophoretic mobility of a subcellular particle, complexed with an antibody directed against the cytoplasmic domain of one of its integral membrane proteins is greatly diminished, provided the pH of the electrophoresis buffer is adjusted to pH approximately 8.0, the pI of immunoglobulin G (IgG) molecules. pH-values other than 8.0 proved to be less efficient, probably because IgG molecules only focus at pH 8.0 but are scattered at any other. Applying IFFE to heavy and light mitochondrial as well as microsomal fractions of rat liver not only regular PO (rho = 1.22-1.24 g/cm(3)) but also other subpopulations could be isolated. To substantiate the validity of this approach, we now have subfractionated mouse liver homogenates accordingly. Of the PO subpopulations collected, mainly that obtained from the heavy mitochondrial fraction differed in its composition of matrix and membrane proteins as revealed by immunoblotting. This is in line with the data reported on rat liver thus confirming the potential of IFFE in the isolation of distinct subpopulations of hepatic PO. 相似文献
77.
Karl-Dieter Müller H. Peter Nalik Ernst N. Schmid Heribert Husmann Gerhard Schomburg 《Journal of separation science》1993,16(3):161-165
Trimethylsulfonium hydroxide (TMSH) reproducibly converts fatty acids bound in, e.g., biomolecules such as phospholipids and/or glycerides, into the corresponding fatty acid methyl esters (FAMEs). The transesterification can be performed at room temperature in a fast single step reaction. Surprisingly, secondary alcohols and mycolic acid cleavage products (MACPs) are also released from mycobacteria under these conditions. The complex reaction mixtures containing FAMEs, MACPs, and secondary alcohols can easily be separated by high resolution temperature-programmed capillary GC. Different species of mycobacteria give rise to characteristic chromatographic patterns and the amount of lipids from a single colony of mycobacteria is sufficient for reliable identification of the bacteria. The profiles of the chromatograms match well those obtained from other sample preparation techniques. The TMSH method of identification of mycobacteria from the patterns of the gas chromatograms is faster and more sensitive than conventional methods, which also involve transesterification. The identification of mycobacterial species by microbiological culture techniques is difficult to perform and requires several weeks. 相似文献
78.
The heat capacities of SnSe and SnSe2 were measured in the temperature range 230–580 K using a computer interfaced differential scanning calorimeter. From these measurements, the Debye temperatures of SnSe and SnSe2 were calculated as a function of temperature. An estimated Debye temperature of 220 K for SnSe was used to calculate the absolute entropy of SnSe at 298 K to be 85.2 ± 6.0 J K?1 mole?1. In the light of other work, the suitability of Debye temperatures for estimating low temperature heat capacities of SnSe2 is questioned. 相似文献
79.
F. Asinger A. Saus H. Offermanns D. Neuray K. H. Lim 《Monatshefte für Chemie / Chemical Monthly》1971,102(1):321-332
Zusammenfassung Bei der Einwirkung von Äthylenimin und Schwefel auf Methyläthylketon, Methylisopropylketon und Äthylisopropylketon entstehen strukturisomere 5,6-Dihydro-1,4-thiazine (1–6) und als Nebenprodukte die dem jeweiligen Keton entsprechenden Thiazolidine (7–9).Die 5,6-Dihydro-1,4-thiazine werden mit Ameisensäure in N-Formylthiomorpholine (10–15) übergeführt, die mit verd. HCl glatt zu den entsprechenden Thiomorpholinen (16–21) hydrolysiert werden.Das Verhältnis der Thiomorpholin-Isomerenpaare wird gaschromatographisch quantitativ bestimmt.
2. Mitt.:F. Asinger, H. Offermanns, K. H. Lim undD. Neuray, Mh. Chem.101, 1281 (1970).
73. Mitt.:F. Asinger, H. Offermanns undD. Neuray, Ann. Chem.739, 72 (1970).
Teil der DissertationK. H. Lim, Techn. Hochschule Aachen, 1969. 相似文献
Concomitant action of elementary sulfur and gaseous ammonia upon ketones, LXXIV: Concomitant action of elementary sulfur and ethylenimine upon ketones, III
The reaction of ethylenimine and sulfur with methyl ethyl ketone, methyl isopropyl ketone and ethyl isopropyl ketone, resp., yields the structurally isomeric 5.6-dihydro-1.4-thiazines (1–6) and as by-products the thiazolidines (7–9) derived from the corresponding ketones.The 5.6-dihydro-1.4-thiazines are converted with formic acid to the N-formyl thiomorpholines10–15, which are easily hydrolyzed with dilute hydrochloric acid to the corresponding thiomorpholines (16–21). The ratio of the pairs of structurally isomeric thiomorpholines is determined by quantitative gas chromatography.
2. Mitt.:F. Asinger, H. Offermanns, K. H. Lim undD. Neuray, Mh. Chem.101, 1281 (1970).
73. Mitt.:F. Asinger, H. Offermanns undD. Neuray, Ann. Chem.739, 72 (1970).
Teil der DissertationK. H. Lim, Techn. Hochschule Aachen, 1969. 相似文献
80.
Zeitschrift für Physik A Hadrons and nuclei - Messungen der komplexen Dielektrizitätskonstanten an Tellureinkristallen zwischen ?170 °C und Zimmertemperatur geben für den... 相似文献