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  • 1985-1989
  • 1965-1969  (559)
  • 1968  (559)
  • Organic Chemistry  (547)
  • Kidney  (12)
  • 1
    ISSN: 1432-2013
    Keywords: Kidney ; Aldosterone ; Tubular Sodium Reabsorption ; Proximal Tubule ; Sodium Chloride Loading ; Niere ; Aldosteron ; tubuläre Natriumresorption ; proximaler Tubulus ; Natriumchloridbelastung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Ratten erhielten 4 Wochen lang isotone Kochsalzlösung als Trinkflüssigkeit. Glomerulumfiltrat und Passagezeit von Lissamin-Grün im proximalen Tubulus blieben unverändert. Die spezifische Resorptionskapazität des Tubulusepithels — gemessen mit der „gespaltenen-Tropfen-Methode“ — nahm signifikant ab. Daraus ergab sich eine Verminderung der fraktionellen Natrium-und Wasserresorption im proximalen Tubulus von 51 auf 38% der gefilterten Menge. Die Na+-Ausscheidung stieg von 0,06 (Kontrollen) auf 1,25% der gefilterten Menge. Diese Veränderungen waren rückgängig zu machen durch Injektion von d-Aldosteron. Durch Bestimmung des TF/P-Inulin-Quotienten am Ende des proximalen Konvolutes wurden die Ergebnisse bestätigt. Es wird angenommen, daß die Resorptionshemmung im proximalen Tubulus bei chronischer Kochsalzbelastung durch verminderte Sekretion von Mineralocorticoiden bedingt und letzten Endes Ursache der vermehrten Na+-Ausscheidung ist. Ein Teil der proximalen Resorptionshemmung wird anscheinend in weiter distal gelegenen Nephron-Abschnitten kompensiert.
    Notes: Summary Rats were kept on isotonic saline as drinking fluid for a period of 4 weeks. Glomerular filtration rate and proximal transit time of Lissamine green remained unchanged. The intrinsic reabsorptive capacity of the proximal tubular epithelium—measured by the “shrinking-droplet-method”—decreased significantly. As a result, fractional proximal reabsorption of sodium and water decreased from 51 to 38 per cent of the filtered load. Sodium excretion rose from 0.06 (controls) to 1,25 per cent of the filtered load. These changes were reversible by injection of d-aldosterone. The results were confirmed by measuring the TF/P ratio of inulin at the end of the proximal convolution. The results indicate that in rats chronically loaded with salt, the inhibition of fractional proximal reabsorption is due to a decreased secretion of mineralocorticoids, and is the cause of the higher sodium excretion. Apparently, the decreased proximal reabsorption is partly compensated in more distal parts of the nephron.
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  • 2
    ISSN: 1432-2013
    Keywords: Kidney ; Concentration ; Dialysis ; Urea ; Electrolytes ; Niere ; Konzentrierung ; Dialyse ; Harnstoff ; Elektrolyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Um den Einfluß des Plasmaharnstoffspiegels auf die Konzentrierfähigkeit der Niere zu untersuchen, wird der Blutkreislauf von Ratten an eine Dialysiervorrichtung angeschlossen und der Harnstoffspiegel des Blutes für 3 Std durch Dialyse gegen eine harnstoffreie Spüllösung gesenkt. Gleichzeitig wird der Harnfluß der Tiere durch eine Regelanordnung konstant gehalten. Die Regelung wird dadurch erreicht, daß dem Blutkreislauf bei zu hohem Harnfluß automatisch Flüssigkeit entzogen und bei zu niedrigem Harnfluß Flüssigkeit zugeführt wird. Es wird gefunden, daß die Harnstoffkonzentrationen im Harn linear mit dem Plasmaharnstoffspiegel abfallen bzw. ansteigen. Die Summe der Elektrolytkonzentrationen fällt dagegen mit dem Plasmaharnstoffspiegel nur wenig ab. Falls ein völliger Harnstoffentzug möglich wäre, würde auch dann noch eine Konzentrierung der Elektrolyte auf mehr als doppelt isoton möglich sein. Die Ergebnisse der Untersuchung lassen sich am einfachsten mit der Annahme interpretieren, daß in der Niere der Ratte zwei unterschiedlich arbeitende Konzentrierungsmechanismen wirksam sind, von denen der eine im wesentlichen Elektrolyte, der andere im wesentlichen Harnstoff konzentriert. Der Konzentrierungsmechanismus für Elektrolyte könnte im äußeren Mark, der für Harnstoff im inneren Mark lokalisiert sein.
    Notes: Summary To investigate the influence of plasma urea levels on the concentrating power of the kidney, the blood circulation of rats was connected to a dialyser; with dialysis against a urea-free cleaning solution, the urea level of the blood was lowered for three hours. During this, the urine flow of the animals was kept constant by a regulating arrangement. This control was achieved by removing fluid from the blood circulation in the case of too high urine flow and by putting in fluid in the case of too low urine flow. It was found that the concentration of urea in the urine had a direct linear relationship with the plasma urea level. The total electrolyte concentration fell only slightly compared to the plasma urea level falls. If the urea could have been completely removed, high concentrating of the electrolyte, to more than double isotonic, would still have been possible. The simplest way to interpret the results of this research is by the hypothesis that two different concentrating mechanisms are at work in the rat kidney, the one essentially concentrating electrolytes, and the other principally urea. The concentrating mechanism for electrolytes could be localised in the outer medulla, and for urea in the inner medulla.
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  • 3
    ISSN: 1432-2013
    Keywords: Kidney ; Concentration ; Infusion ; Urea ; Electrolytes ; Niere ; Konzentrierung ; Infusion ; Harnstoff ; Elektrolyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Um die gegenseitige Beeinflussung von Harnstoff und NaCl bei der Bildung eines konzentrierten Harns zu untersuchen, werden Ratten 2 Tage lang NaCl-Lösungen mit wechselndem Harnstoffgehalt infundiert. Sodann werden der Harn sowie das Gewebe der Nierenrinde, des äußeren Marks und des inneren Marks auf ihren Gehalt an Kalium, Natrium und Harnstoff analysiert. Es wird gefunden, daß die Konzentrierfähigkeit der Rattenniere unter diesen Versuchsbedingungen für NaCl bei gleichzeitiger Zufuhr von Harnstoff geringer wird. In der Niere steigen NaCl und Harnstoffkonzentrationen unter allen Infusionsbedingungen von der Nierenrinde zur Nierenpapille hin an. Bei Infusion reiner NaCl-Lösungen entsprechen die NaCl- und Harnstoffkonzentrationen im Harn denen in der Papille. Bei Infusion von harnstoffhaltigen NaCl-Lösungen sind im Harn die NaCl-Konzentrationen höher und die Harnstoffkonzentrationen niedriger als im Papillengewebe. Diese Ergebnisse schließen aus, daß die hohen Harnstoffkonzentrationen im Nierenmarkgewebe durch einfache Diffusion des Harnstoffes aus den Sammelrohren in das Nierenmarkgewebe zustande kommen. Es wird die Möglichkeit diskutiert, daß die Harnstoffkonzentrierung unter den hier wiedergegebenen Versuchsbedingungen durch Gegenstromdiffusion in dem Vasa recta-System verursacht wird. Der Konzentriereffekt hierfür könnte durch einen Wasserfluß aufgrund osmotischer Kräfte von dem Blutgefäßsystem in die Henleschen Schleifen zustande kommen, wenn der Harn in den Henleschen Schleifen durch Aufnahme von NaCl, das aus den Sammelrohren stammt, hyperton wird.
    Notes: Summary To investigate the mutual interdependence of urea and sodium in producing concentrated urine, solutions of different concentrations of sodium and urea were infused into the stomach of rats. After two days' infusion, the urine and tissues from the different zones of the kidneys were analysed for sodium, potassium and urea content. It was found that the efficiency of the rat kidney in producing urine with high sodium content was diminished if urea was infused together with the sodium chloride. Under all conditions sodium and urea concentrations increased from the cortex to the papilla of the kidneys. When pure sodium chloride solutions were infused, sodium and urea concentrations in the urine were nearly equal to the corresponding concentrations in the papilla. Infusion of solutions containing NaCl and urea caused production of urine with a higher sodium concentration and lower urea concentration than in the papilla. These results show that the high concentration of urea in the medulla of the kidney does not arise by passives diffusion of urea from the collecting ducts into the medullary tissue. The possibility that the concentration of urea in the inner medulla is produced by counter current diffusion of urea in the vasa recta is discussed. The concentration effect necessary for this counter current multiplication could be created by an osmotic flow of water from the vasa recta into loops of Henle, if the urine in the loops becomes hypertonic by taking up sodium chloride from the collecting ducts.
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  • 4
    ISSN: 1432-2013
    Keywords: Tubules ; Kidney ; Intraluminal Oil Injection ; Ultrastructure of Kidney ; Proximales Tubuluskonvolut ; Rattenniere ; intraluminale Ölinjektion ; Ultrastruktur der Niere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Light- and electronmicroscopic evaluation of proximal convolutions of the rat kidney were made following injection with either mineral oil or castor oil. The following observations were made: 1. Injection of mineral oil does not result in a complete blockade of the tubular lumen and leads to morphological lesions of epithelial cells. 2. Injection of the more viscous castor oil, in contrast, leads to a dilatation of the tubular lumen and a compression of the brush border of proximal tubular cells. Thus a better blockade of longitudinal flow is achieved. A toxic effect of castor oil on the tubular epithelium could not be detected. Mechanical lesions, similar to those observed after mineral oil injection, were less frequent. They consisted in a penetration of oil into the cells, perhaps as consequence of the tubular dilatation. 3. In oil-injected proximal tubular segments the following cytologic phenomena were observed: a) a cessation of the normal pinocytosis, which is induced in the presence of tubular fluid, b) simultaneously the “large resorption vacuoles” disappear, indicating that they originate from confluence of pinocytotic vesicles, c) in dilated tubules protein resorption vacuoles are found to have ruptured towards the tubular lumen suggesting a high hydrostatic pressure within the vacuoles.
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  • 5
    ISSN: 1432-2013
    Keywords: Kidney ; Experimental Hypertension ; Tubular Sodium Reabsorption ; Tubular Water Reabsorption ; Henle's Loop ; Niere ; experimenteller Hochdruck ; tubuläre Natriumresorption ; tubuläre Wasserresorption ; Henlesche Schleife
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 4 Wochen nach Klammerung einer Nierenarterie war der Perfusionsdruck der geklammerten Niere normal, während der arterielle Mitteldruck auf 188 mm Hg angestiegen war. Die Ausscheidung von Natrium und Wasser im Harn der geklammerten Niere war normal, im Harn der ungeklammerten Niere erheblich höher als normal. Glomerulumfiltrat (pro g Niere), intratubulärer Druck, Tubulusweite, Passagezeit von Lissamingrün und die fraktionelle Resorption von Natrium und Wasser waren im proximalen Tubulus sowohl in der geklammerten wie in der ungeklammerten Niere normal. In der ungeklammerten Niere war die Passagezeit durch die Henlesche Schleife stark verkürzt und die Resorption von Natrium und Wasser in der Schleife erheblich vermindert. Diese Veränderungen — obwohl zum Teil kompensiert durch vermehrte Resorption im distalen Tubulus und im Sammelrohr — sind verantwortlich für die höhere Wasser- und Natriumausscheidung der ungeklammerten Niere. Die Ursache ist wahrscheinlich eine stärkere Durchblutung des Nierenmarkes. Im Nephron der geklammerten Niere war die fraktionelle Natrium- und Wasserresorption nicht signifikant von normalen Werten verschieden mit der Ausnahme einer niedrigeren Natriumresorption im distalen Tubulus und einer höheren Natriumresorption im Sammelrohr. Der Natrium-Transport im distalen Tubulus ist anscheinend gestört; TF/P−Na+ betrug im Mittel 0,6 bis zum Ende des distalen Tubulus. Die Ergebnisse können die unterschiedliche Harnausscheidung erklären, die beim Hypertoniker mit einseitiger Nierenarterienstenose beobachtet wird (Howard-Test).
    Notes: Summary Four weeks after clamping one renal artery, the perfusion pressure of the clamped kidney was normal whereas the mean arterial pressure had increased to 188 mm Hg. Urinary excretion of sodium and water of the clamped kidney had not changed while that of the untouched kidney increased considerably. Glomerular filtration rate (per g kidney), intratubular pressure, tubular diameter, transit time of Lissamine green and fractional sodium and water reabsorption of the proximal tubule were normal in both the clamped and the untouched kidney. In the untouched kidney, the transit time through Henle's loop was shortened and the sodium and water reabsorption in it was significantly reduced. These changes, although partly compensated by higher reabsorption in the distal tubule and collecting duct, are responsible for the increased sodium and water excretion of the untouched kidney. They are probably due to an increased medullary blood flow. In the clamped kidney, fractional sodium and water reabsorption of the whole nephron did not differ significantly from normal values. However, sodium reabsorption was lower in the distal tubule and higher in the collecting duct. Sodium transport in the distal tubule seemed to be impaired; throughout its length sodium TF/P ratio averaged 0.6. These results may explain the different urinary excretion found in human hypertension following unilateral renal artery stenosis (Howard-Test).
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  • 6
    ISSN: 1432-2013
    Keywords: Kidney ; Fluxes ; Osmotic Gradients ; Niere ; Flüssigkeits-Substanzbewegungen ; osmotische Gradienten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Durch artifizielle osmotische Druckdifferenzen von 150 mOsmol/l zwischen Lumen- und Blutseite der Tubulusepithelien von Rana ridibunda wird Flüssigkeit im Richtungssinne der Reabsorption oder — in geringerem Maße — der Sekretion längs des osmotischen Gradienten bewegt. Na+ wird in jedem Fall „trocken” reabsorbiert. Bei mit Furosemid blockiertem aktiven Na+-Transport läuft isoton Flüssigkeit längs des osmotischen Gradienten aus dem Tubuluslumen in das blutseitige Medium. Bei umgekehrt gerichtetem Gradienten wird das Filtrat so verändert, als ob es durch Einstrom reinen Wassers verdünnt würde. Die Tubulusepithelien verhalten sich so, als besäßen sie — im Zustand des blockierten aktiven Na+-Transportes — ein „Rückschlagventil” für Na+. Wenn der osmotische Gradient so gerichtet ist, daß Wasser oder Flüssigkeit aus dem Lumen in das blutseitige Medium läuft, dann kommt es bei umgekehrt gerichtetem Na+-Konzentrationsgradienten nicht zum Einstrom von Na+ in das Tubuluslumen. Die Na+-Harnkonzentration sinkt beträchtlich unter die des Perfusates, was als Ausdruck einer Na+-Reabsorption gegen den Konzentrationsgradienten gedeutet wird. Bei Blockierung des Na+-Transportes durch Furosemid kommt es wiederum zum Einstrom reinen Wassers in die Tubuluslumina. Die Versuche mit durch Furosemid blockiertem Na+-Transportmechanismus sind beweisend, daß die Tubuli für Na+ im Richtungssinne der Sekretion impermeabel sind. Die „Verdünnung” des Tubulusinhaltes durch einen osmotischen Gradienten, der Wasser in die Tubuli hineinlaufen läßt, kommt also nicht durch ein Überwiegen der Reabsorption über die „Sekretion” zustande. Wird statt des leicht penetrierenden Na-Chlorids das schwer penetrierende Natriumcyclohexansulfamat angeboten, dann wird absolut gegenüber den Versuchen mit Na-Chlorid weniger Na+ transportiert. Im übrigen zeigen die Nieren jedoch das gleiche Verhalten wie bei Angebot von Na-Chlorid.
    Notes: Summary Osmotic gradients of 150 mosmol/l between intratubular fluid and blood in the kidney of Rana ridibunda induce a fluid movement down the osmotic gradient which is stronger into the tubule than out of it. In either case Na+ is reabsorbed “dry”. If the active Na+-transport is blocked by Furosemid an osmotically downhill movement of isotonic fluid out of the tubule obtains. Reversal of the osmotic gradient induces a reversal of flow but the inward moving fluid is diluted. The tubular cells seem to inhibit the backwash of Na+. If the osmotic gradient induces an outflow of fluid out of the tubule no influx of Na+ occurs even in the presence of a concentration gradient for Na+ in the opposite direction. The Na+-concentration in the urine falls considerably below that of the perfusion fluid. This finding indicates Na+-reabsorption against a concentration gradient. Upon blocking of the Na+-transport by Furosemid water enters the tubules. The results of the experiments in which the Na+-transport was blocked by Furosemid prove that the tubules are impermeable for Na+ in the direction of secretion. The “dilution” of the tubular fluid as a result of an osmotic gradient which induces an influx of water isnot due to a reabsorption outbalancing “secretion”. If instead of the easily penetrating NaCl the slowly penetrating Na+-cyclohexanesulphamate is used, less Na+ is transported. However, in every other respect the results obtained are similar to those described above.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 304 (1968), S. 336-350 
    ISSN: 1432-2013
    Keywords: Kidney ; Experimental Hypertension ; Distal Tubular Sodium Reabsorption ; Distal Osmolality ; Tubular Potassium Secretion ; Niere ; experimenteller Hochdruck ; distale Natrium resorption ; distale Osmolalität ; tubuläre Kaliumsekretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Vier Wochen nach Klammerung einer Nierenarterie wurde die Funktion des distalen Tubulus untersucht. In der ungeklammerten, unter dem hohen Blutdruck stehenden Niere blieb die Tubulusflüssigkeit bis 90% distaler Tubuluslänge hypoton. Dies wird auf eine erhöhten Flüssigkeitseinstrom aus der Henleschen Schleife zurückgeführt; eine verminderte Wasserpermeabilität des distalen Tubulus konnte nicht nachgewiesen werden. In der geklammerten Niere war mit Ausnahme des frühdistalen Abschnittes die Natriumkonzentration on jeder Stelle des distalen Konvolutes signifikant höher als in der ungeklammerten Niere und in Kontrollnieren. Auch fehlte im distalen Tubulus der geklammerten Niere eine Nettokaliumsekretion. die distale Gleichgewichtskonzentration für Natrium war auf der geklammerten Seite erhöht, auf der ungeklammerten Seite normal. Der isotone Natriumausstrom (Methode des gespaltenen Tropfens) war in der geklammerten Niere vermindert, in der ungeklammerten Niere erhöht. Die frühdistale Harnstoffkonzentration war in der ungeklammerten Niere gegenüber der geklammerten Niere und Nieren von Kontrollratten erniedrigt. Spätdistal war TF/P-Harnstoff in beiden Nieren gleich. Beide Nieren hatten ein normales Glomerulumfiltrat und normale tubuläre Passagezeiten mit Ausnahme einer verkürzten Schleifenzeit in der ungeklammerten Niere. Die Befunde werden dahingehend interpretiert, daß der aktive Natriumtransport im distalen Tubulus der beiden Nieren voneinander verschieden ist, möglicherweise infolge des unterschiedlichen Reningehaltes der beiden Nieren.
    Notes: Summary Four weeks after constricting one renal artery distal tubular function was studied using the micropuncture technique. In the untouched kidney tubular fluid remained hypotonic up to 90% distal tubular length. We believe this to be the result of the high inflow of tubular fluid from Henle's loop. A reduced permeability for water could not be demonstrated. Except for the early part of the distal tubule there was a marked increase in sodium concentration in the clamped kidney as compared to values obtained in the untouched one and in kindneys of control animals. In addition no potassium secretion could be observed in the clamped kidney. The distal steadystate concentration for sodium was increased in the clamped kidney and normal in the untouched one. Reabsorptive half-time, measured by the split droplet technique, was prolonged in the clamped kidney and shortened in the untouched one. Early distal urea concentration was lower in the untouched kidney than in the clamped one and in control kidneys, while at the end of the distal tubule urea concentrations did not differ significantly. Both kidneys had normal glomerular filtration rates and proximal tubular transit times, whereas a shortened transit time through Henle's loop of the untouched kidney was found. The results indicate that active sodium transport in the distal tubule of the clamped kidney differs from that of the untouched one, possibly due to the different renin concentration in both kidneys.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 305 (1968), S. 96-104 
    ISSN: 1432-2013
    Keywords: Blood Circulation Time ; Kidney ; Plasma ; Radioautography ; Radioisotope Dilution Technique ; Regional Blood Flow ; Mittlere Kreislaufzeit ; Niere ; Plasma ; Autoradiographie ; Isotopenverdünnungstechnik ; Regionale Nierendurchblutung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary At different times after injection into the renal artery of131I-albumin, the distribution of the tracer in kidneys of the rabbit and the dog was illustrated by a series of autoradiograms. In order to determine the mean circulation time for albumin in the kidney, the radioactivity over the kidney was simultaneously registered by external monitoring. A short mean circulation time was measured for albumin (plasma) passing cortex, and a longer one for that fraction of the albumin that passed through medulla, papillae, and capsule. The investigation rendered probable that the mean circulation time for blood through the kidney determined by the external technique applies to blood passing cortex. The circulation times for blood through medulla, papillae, and capsule are not included in the calculation of the mean circulation time.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Archives of toxicology 23 (1968), S. 245-249 
    ISSN: 1432-0738
    Keywords: Bone ; Strontium poisoning ; Parathormone ; Kidney ; Knochen ; Strontiumvergiftung ; Parathormon ; Niere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Restitution des strontiumgeschädigten Skelets wachsender Sprague Dawley Ratten ist von einem Anstieg der dialysablen Strontium- und Calciumfraktion des Serums begleitet. Die Ergebnisse legen eine Beeinflussung der renalen Manipulation von Kationen bei Knochenschädigungen durch Fremdmetalle nahe.
    Notes: Summary Restitution of skeletal damage caused by strontium in growing Sprague Dawley rats is accompanied by an increase in the dialysable serum fractions of strontium and calcium. The results suggest that the renal manipulation of cations is influenced in bone lesions caused by foreign metals.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Clinical and experimental medicine 145 (1968), S. 270-277 
    ISSN: 1591-9528
    Keywords: Aldosterone ; Kidney ; Stop flow dog ; Aldosteron ; Niere ; Stop flow-Hund
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Mit Stop flow-Versuchen an Hunden konnten wir nach Infusion von 1,2-3H-18-Aldosteronglucuronid im Gegensatz zur Infusion von freiem 1,2-3H-Aldosteron keine proximale Sekretion von 1,2-3H-18-Aldosteronglucuronid nachweisen. Daraus kann geschlossen werden, daß in Hundenieren die proximalen Tubuluszellen wohl 18-Aldosteronglucuronid aus Aldosteron bilden und an das Tubuluslumen abgeben, während im Nierenarterienblut vorhandenes 18-Aldosteronglucuronid nur glomerulär filtriert und ausgeschieden wird.
    Notes: Summary In stop flow experiments during infusion of 1,2-3H-18-aldosterone glucuronide there was no proximal tubular secretion of this metabolite in contrary to experiments during infusion of 1,2-3H-aldosterone. The discrepancy must be explained by formation of 1,2-3H-aldosterone glucuronide out of3H-aldosterone in proximal tubular cells, while the 1,2-3H-18-aldosterone glucuronide in the plasma of the renal artery blood is only filtered in the glomerulum.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Clinical and experimental medicine 146 (1968), S. 336-345 
    ISSN: 1591-9528
    Keywords: Aldosterone ; Kidney ; Man ; Aldosteron ; Niere ; Mensch
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Auf Grund eines Vergleiches der Verhältnisse von 1,2-3HTetrahydroaldosteronglucuronid zu 1,2-3H-18-Aldosteronglucuronid im Plasma von drei Normalpersonen und zwei nephrektomierten Patienten nach einer Injektion von 1,2-3H-Aldosteron haben wir folgende Schlüsse in Betracht gezogen: 1. Das im Blutplasma vorhandene 1,2-3H-18-Aldosteronglucuronid wird nur glomerular filtriert. 2. Die renale Clearance von 18-Aldosteronglucuronid, die etwa das Fünffache der Inulinclearance beträgt [13, 15], mu\ zu vier Fünfteln auf Bildung von 18-Aldosteronglucuronid durch die proximalen [15] Tubuluszellen zurückgeführt werden. 3. Das Ausma\ der renalen Bildung von 18-Aldosteronglucuronid liegt in einer Grö\enordnung von 80% der Gesamtmenge 18-Aldosteronglucuronid im 24 StdUrin.
    Notes: Summary After an intravenous injection of 1,2-3H-aldosterone the ratios of 1,23H-tetrahydroaldosterone glucuronide to 1,2-3H-aldosterone glucuronide in the blood plasma of three normal and two nephrectomized persons were compared. In the three normal persons the ratios were of the same magnitude as in the two nephrectomized persons. On the basis of glomerular filtration of tetrahydroaldosterone glucuronide, as previously demonstrated by renal clearance studies in man [13, 15] and stop flow experiments in dogs [6], we made the following deductions: 1. 18aldosterone glucuronide in blood plasma is only filtered in the glomerulum. 2. The renal clearance of 18-aldosterone glucuronide, as investigated during aldosterone infusion in man [13, 15], therefore must be explained by glomerular filtration of only one fifth and by formation of four fifth of 18-aldosterone glucuronide by proximal [15] tubular cells. 3. This means that about 80% of 18-aldosterone glucuronide excreted in urine is formed by the kidneys.
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  • 12
    ISSN: 1591-9528
    Keywords: Plasma FFA composition ; Individual FFA extraction in heart ; Skeletal muscle ; Kidney ; Plasma-FFS-Zusammensetzung ; Extraktion der Einzel-FFS in Herz ; Skeletmuskel ; Niere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei narkotisierten Hunden wurden die arteriovenösen Differenzen der gesamten und der einzelnen freien Fettsäuren (FFS) am Herzen, am elektrisch stimulierten Skeletmuskel (M. gastrocnemius) und an der Niere bei verschieden hoher arterieller FFS-Konzentration untersucht. Die Konzentration der gesamten FFS wurde titrimetrisch, ihre Zusammensetzung wurde gaschromatographisch bestimmt. Bei einer Steigerung der FFS-Konzentration durch Noradrenalininfusionen stiegen die Anteile der öl- und der Palmitinsäure an, und die Anteile der Stearin- und der Linolsäure sanken ab. Bei einer Senkung der FFS-Konzentration durch Glucoseinfusionen nahmen die Anteile der öl- und der Palmitoleinsäure ab, und die Anteile der Palmitin- und der Stearinsäure nahmen zu. Unter Kontrollbedingungen entfielen am Herzen 44% der gesamten FFS-Extraktion auf die öl- und 24% auf die Palmitinsäure, am Skeletmuskel entfielen 43% auf die öl- und 29% auf die Palmitinsäure. Bei einer Steigerung der arteriellen FFS-Konzentration durch Noradrenalin extrahierten Herz- und Skeletmuskel nur noch öl-, Palmitin- und Palmitoleinsäure. Gleichzeitig wurde im Herz Stearin- und Linolsäure und im Skeletmuskel Stearinsäure produziert. In der Niere entfielen unter Kontrollbedingungen je 40% der Gesamt-FFS-Extraktion auf die Palmitin- und die ölsäure. Es wird gefolgert, daß die öl-, die Palmitin- und die Palmitoleinsäure gegenüber den anderen FFS bevorzugt als Energiequellen benutzt werden, weil bei gleicher arterieller Konzentration höhere Extraktionen für diese drei FFS gemessen wurden. Noradrenalin bewirkt, wahrscheinlich durch Aktivierung von Lipase, im Herzen und im arbeitenden Skeletmuskel einen Abbau von gespeicherten oder im Plasma transportierten Triglyceriden.
    Notes: Summary The arteriovenous differences of total and individual free fatty acids (FFA) have been determined in the myocardium, in the electrically stimulated skeletal muscle (gastrocnemius) and in the kidney of closed chest anesthetized dogs. The concentration of total FFA was determined by titration, their composition was determined by gaschromatography. When the arterial concentration of total FFA was increased by norepinephrine infusions the percentage of olic and of palmitic acid increased and the percentage of stearic and linolic acid decreased. When the concentration of total FFA was decreased by glucose infusions the percentage of olic and palmitolic acid decreased and the percentage of palmitic and stearic acid increased. Under control conditions in the myocardium 44% of the total FFA extraction were related to olic and 24% to palmitic acid and in the skeletal muscle 43% were related to olic and 29% to palmitic acid. During norepinephrine induced increases of arterial FFA concentration myocardium and skeletal muscle extracted only olic, palmitic and palmitolic acid. At the same time in the myocardium stearic and linolic acid and in the skeletal muscle stearic acid was produced. In the kidney under control conditions 40% of the total FFA extraction were related to palmitic and 40% to olic acid. Since the extraction of olic, palmitic and palmitolic acid was higher than the extraction of other FFA at comparable arterial concentrations, it is concluded, that these three FFA are used in preference to other FFA as energy sources. Norepinephrine causes, probably via activation of lipase, in the myocardium and in the working skeletal muscle a breakdown of stored or in plasma transported triglycerides.
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  • 13
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 59-63 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,4-Dinitrobutan läßt sich mit Formaldehyd zum 2,5-Bis-(hydroxymethyl)-2,5-dinitro-hexan-1,6-diol (I) umsetzen. Durch katalytische Hydrierung konnte daraus das 2,5-Bis-(hydroxymethyl)-2,5-diamino-hexan-1,6-diol (II) gewonnen werden. Mit Formaldehyd und primären Aminen liefert I 1,2-Bis-[5′(5′-nitro-1′,3′-dialkyl-hexahydro-pyrimidyl)]-äthane (III) und 1,2-Bis-[5′(5′-nitro-3′-alkyl-tetrahydro-1′,3′-oxazinyl)]-äthane (IV).
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  • 14
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 243-251 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wurden verschiedenartig substituierte Acetylphenylester der Phosphor- und Thiophosphorsäure hergestellt und deren Wirksamkeit gegen Musca domestica geprüft. Es zeigte sich, daß eine lineare Abhängigkeit sowohl zwischen dem LD50-Wert und dem pK-Wert als auch zwischen dem LD50-Wert und der Verschiebung der Frequenz der OH-Valenzschwingung der zur Veresterung herangezogenen Phenole besteht, wenn diese in m- oder p-Stellung substituiert sind. Bei mehrfacher Substitution konnte diese Übereinstimmung nicht gefunden werden, da durch Wasserstoffbrückenbindung (o-Acetylphenol) oder sterische Hinderung, speziell bei angularen Erstsubstituenten (NO2- und COCH3Gruppe), die erwarteten Substitutionseinflüsse nicht voll wirksam werden.
    Additional Material: 2 Ill.
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  • 15
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 97-101 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über Darstellung und Eigenschaften von p-Nitrosocumol. p-Cumylborsäure, p-Cumylquecksilberacetat und einigen hiervon abgeleiteten Verbindungen berichtet, die als Modelle für substituierte Polystyrole dienen könen.
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  • 16
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es werden die Ergebnisse von Phasengleichgewichtsmessungen am genannten System bei einer Schnittemperatur von 45,0 °C mitgeteilt. Des weiteren wird versucht, die Konzentrationsabhängigkeit des Phasengleichgewichtes durch einen ternären MARGULES-Ansatz zu interpretieren und die von SCHUBERTH in (2) dargelegte Behauptung der besseren Darstellbarkeit mit B′=B′13 + B′23 gegenüber B′ = 0 zu überprüfen. Die hinreichend konsistenten Meßergebnisse scheinen eine Bestätigung der aufgestellten Behauptung zu erbringen.
    Additional Material: 5 Ill.
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  • 17
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 182-191 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Heterocyclische Hydrazine reagieren mit 2-Amino-1,3,4-oxdiazolen in Gegenwart von HCl unter Bildung von 1-Acyl-diaminoguanidinen, die in 5-Stellung heterocyclisch substituiert sind und bei der Oxydation 1-Acyl-C-amino-formazane liefern.In siedender Alkalilauge cyclisieren die Diaminoguanidine zu den Azobasen der in Nβ-Stellung heterocyclisch substituierten 5-Hydrazino-1,2,4-triazole.
    Additional Material: 3 Tab.
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  • 18
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 19
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 214-224 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über das Verhalten von Äthylaluminiumsesquichlorid, Triäthylaluminium und Diäthylaluminiumhydrid gegenüber Methylenchlorid, Chloroform und Tetrachlorkohlenstoff unter verschiedenen Reaktionsbedingungen berichtet.Methylenchlorid und Chloroform werden durch Äthylaluminiumsesquichlorid nicht angegriffen, durch Triäthylaluminium langsam enthalogeniert. Dagegen reagiert Tetrachlorkohlenstoff sehr heftig mit den ersten beiden Äthylaluminium-Verbindungen und führt zu Explosionen. Methylenchlorid eignet sich sehr gut als Lösungsmittel für aluminiumorganische Synthesen, wie bei der Darstellung von Ketonen aus Säurechloriden mit Hilfe von Äthylaluminiumsesquichlorid gezeigt wird.
    Additional Material: 6 Tab.
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  • 20
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 252-256 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Entgegen einer älteren Literaturangabe, wonach Einwirkung von Luftsauerstoff auf Isobutyraldehyd-diphenylaminal zu Hydrazobenzol führen soll, wurde festgestellt, daß unter C—C-Spaltung Diphenyl-formamidin entsteht. Die Reaktion läßt sich auf Aminale des p-Toluidins und des p-Chlor-anilins übertragen.
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  • 21
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 263-268 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Iron(III) forms in the aqueous medium a green complex with 8-hydroxy quinoline 7-sulfonic acid with maximum absorbence at 610 mμ, stable in the pH range 3-4. The composition of the complex as established by three different methods spectrophotometrically is Fe(III) EHQS (where EHQS is the abreviation used for 8-hydroxy quinoline 7-sulfonic acid). The stability constant calculated by the methods of BANERJI and DEY (1) and themole-ratio method (2) was found to be log K = 3.8 ± 0.05 at 25°C and the heat of formation was found to be = -5.24 k. cal/mole at 25°C.
    Additional Material: 6 Ill.
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  • 22
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 1-5 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1,4-Dioxan, Tetrahydrofuran and Dimethoxyäthan wurden unter Hochvakuum-Bedingungen über Kalium getrocknet und anschließend entgast. Die UV-Spektren und die elektrischen Leitfähigkeiten der hochgereinigten Äther wurden gemessen. Die Lösungsmittel konnten unter Hochvakuum-Bedingungen für einen beliebig langen Zeitraum ohne Veränderungen dieser physiko-chemischen Eigenschaften aufbewahrt werden. Behandlung mit Kalium unter Hochvakuum-Bedingungen führte zu einer teilweisen Spaltung der hochgereinigten Äther und hatte eine erhöhte elektrische Leitfähigkeit und Lichtabsorption zur Folge.
    Notes: 1,4-Dioxan, Tetrahydrofuran and Dimethoxyethan were dried over potassium and subsequently degassed, under high vacuum conditions. The u. v. spectra and the electric conductivities of the high purity ethers were measured. The solvents could be stored under high vacuum conditions for an unlimited period of time, without any changes of their physico-chemical properties. Treatment with potassium under high vacuum conditions caused a partial cleavage of the high purity ethers resulting in increased electric conductance and absorption of light.
    Additional Material: 4 Ill.
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  • 23
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 64-71 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird die Synthese neuer Theophyllin- und Coffein-mercapto-essig- und -propionsäuren sowie einiger Ester derselben beschrieben.
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  • 24
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 91-96 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Über die Bildung von p-Nitrosopolystyrol bei der Reaktion von Polystyrolquecksilberacetat mit Nitrosylchlorid wird berichtet, und es werden einige Umsetzungen an p-Nitrosopolystyrol beschrieben.
    Additional Material: 2 Ill.
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  • 25
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 113-121 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Durch kinetische Untersuchungen der Oxiranringöffnung mit Hilfe von Modellsubstanzen wird gefunden, daß die sterische Behinderung der Epoxidgruppe am Bicycloheptanring von Dicyclopentadien-dioxid bei der Reaktion mit Halogenwasserstoff in Dioxan nicht auf die Endomethylengruppe, sondern auf das während der Reaktion primär gebildete Halogenhydrin am Cyclopentanring zurückzuführen ist.Der starke Unterschied in der Reaktivität von HCl und HBr bei der Oxiranringöffnung von Dicyclopentadiendioxid in wasserfreiem bzw. wasserhaltigem Dioxan findet seine Erklärung in unterschiedlicher Protonenkonzentration des Reaktionsmediums. H0-Messungen mit verschiedenen Indikatoren liefern für HBr-Dioxan-Lösungen stets niedrigere H0-Werte als für entsprechende HCl-Dioxan-Lösungen.
    Additional Material: 12 Ill.
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  • 26
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 27
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 41-46 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird die Protonierung der mit Thiotroponen iso-π-elektronischen Trithione (I), Isotrithione (II) und α-Dithiopyrone (III) sowie die Protonierung des Dithiobenzoesäure-methylesters (IV) und der cyclischen Trithiocarbonate (V) in wäßriger Schwefelsäure untersucht. Die H0-Werte der Halbprotonierung werden spektrophotometrisch abgeleitet und die Basizitäten mit den HMO-Elektronendichten verglichen.
    Additional Material: 1 Ill.
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  • 28
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 72-77 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Umsetzungen von 1,8-Bis-brommethyl-naphthalin mit Dimethylsulfoxid, Na2S, NH3 und N-Bromsuccinimid werden beschrieben. Aus 1,8-Bis-dibrommethyl-naphthalin wurde über 1,3-Dimethoxy-1 H, 3H-naptho[1,8-cd]pyran und 1,3-Dihydroxy-1H,3H-naphtho[1,8-cd]pyran Naphthalin-1,8-dialdehyd dargestellt.
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  • 29
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968) 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 30
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 137-142 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über die Darstellung eines makromolekularen Polyradikals vom Diphenylstickstoffoxid-Typ berichtet. Die Struktur wird durch UV- und ESR-Spektren belegt.
    Additional Material: 5 Ill.
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  • 31
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 200-205 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über die Darstellung und Eigenschaften von Diselenoxanthogen-, Diselenokarbaminsäureestern, einigen Selenoharnstoffen und über die Reaktion von Diselenoxanthogenat mit Phosphoroxychlorid berichtet. Auf Versuche zur Darstellung von Bis(N,N-dialkylselenokarbamyl) diseleniden wird hingewiesen.
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  • 32
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 225-233 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The four geometric isomers of the 1,2,4-trimethylcyclohexanes, ctt, ctc, cct and ccc have been synthesized, characterized and their physical constants determined.In the course of the work the stereospecifity of a catalytic reduction method of some olefins and the WOLFF-KISHNER reduction of some ketones were demonstrated.
    Additional Material: 4 Ill.
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  • 33
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 234-242 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Für die Bestimmung von Zink in Pflanzensubstanzen eignen sich absorptionsflammen-photometrische und polarographische Methoden.Mit den zur Verfügung stehenden Gerätekombinationen konnten Messungen im Bereich von 1-5 μg Zn/ml bzw. 1-25 μg Zn/ml Meßlösung vorgenommen werden. Die Streubereiche betragen ±3,17 ppm bzw. ±3,25 ppm. Für die polarographische Bestimmung müssen störendes Phosphat und Sulfat durch Passage einer Kationenaustauschersäule abgetrennt werden. Die absorptionsflammenphotometrische Bestimmung wird durch die in Pflanzenproben vorliegenden Anionen und Kationen nicht gestört, sofern die Messung in 0,1 n HCl erfolgt. Für serienmäßige Arbeiten eignet sich das letztgenannte Verfahren besser, da mit dem polarographischen Verfahren bei gleicher Aufschlußprozedur nur die Hälfte an Bestimmungen geschafft wird. Dagegen ergibt sich bei diesem die Möglichkeit, in geringen Meßlösungsmengen von 0,5 ml zu messen. Die atomabsorptionsphotometrische Methode benötigt mindestens 3 ml Meßlösung.
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 257-262 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monoalkylhydrazine werden erhalten, indem man in wäßriger Lösung Cyclohexanon nd ein Alkylamin mit Hydroxylamin-O-sulfonsäure zu einem 1-alkyl-3,3-pentamethylendiaziridin umsetzt und dieses nach Extraktion mit Toluol ohne Isolierung zu Monoalkylhydrazin und Cyclohexanon hydrolysiert. Durch Umsetzung von Monoalkylhydrazinen mit Kaliumcyanat zu 2-Alkyl-semicarbaziden und deren Fällung mit p-Nitrobenzaldehyd lassen sich gut kristallisierende Derivate herstellen. Durch Aminierung mit Hydroxylamin O—N-disulfonsäure werden Monoalkylhydrazine zu Stickstoff und zum entsprechenden Alkan abgebaut; letzteres wird gaschromatographisch identifiziert.
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  • 35
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 269-277 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Bei der Umsetzung von Aldonsäurehydraziden mit Bromcyan entstehen 2-Amino-5-polyhydroxyalkyl-1,3,4-oxidiazole, die sich mit Wasser in die entsprechenden Semicarbazide, mit Laugen in die entsprechenden 1,2,4-Triazolone-(5) umwandeln lassen. Die Polyhydroxy-1,3,4-oxidiazole lassen sich total acetylieren.
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  • 36
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 301-301 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 37
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 311-318 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es werden Versuche zur Darstellung 5′-substituierter Thymidine aus 5′-O-Arylsulfonylthymidinen beschrieben. Während die Knüpfung neuer C—O- oder von C—S-Bindungen nach Austritt der Arylsulfonyloxy-Gruppe am C-5′ prinzipiell möglich ist, wird bei Versuchen zur Knüpfung einer C—C-Bindung am C-5′ mit Kaliumcyanid O2,5′-Cyclo-thymidin erhalten. Mit Ammoniak reagieren die 5′-O-Arylsulfonyl-thymidine über O2,5′-Cyclothymidin zu 1-(2′-Desoxyribofuranosyl)-5-methyl-isocytosin und 5-Methylisocytosin.
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  • 38
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 9-19 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Der Hexamycinbildner 4/122 gehört zur Gattung Streptomyces. Für die Fermentation erwies sich ein Nährmedium mit Sojabohnenmehl am geeignetsten. Das Hexaenantibiotikum wurde aus dem Myzel mit Methanol und aus dem Kulturfiltrat mit n-Butanol extrahiert. Nach Abtrennen eines „ätherlöslichen Antibiotikums“ wurde das Rohprodukt mit Wasser extrahiert und durch Craig-Verteilung im System n-Propanol-Äther-Wasser (1:3:3) gereinigt. Lyophilisation aus tert.-Amylalkohol führte zu einer gelben, amorphen. Substanz.
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  • 39
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 50-56 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird die Synthese des vollständig geschützten Pentapeptids BOC-Orn(Z)-D-Leu-Ile-Orn(Z)-Orn(Z)-OMe beschrieben. Der Aufbau gelingt vorteilhaft durch stufenweise Synthese vom Carboxylende her unter Benutzung der Carbodiimid-, gemischten Anhydrid und Nitrophenylester-Methode.
    Additional Material: 1 Ill.
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  • 40
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 88-100 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die WOLFF-Umlagerung der 1-Phthaloylamino-3-diazo-alkanone-(2) I a-d in Gegenwart von Anilin, DL-α-Phenyläthylamin, DL-β-Amino-β-phenyl-propionsäureäthylester and DL-Phenylalaninestern unter katalytischer Wirkung von Silberoxid oder durch Photolyse führt zu Derivaten des β-Alanins, der β-Amino-α-methyl-propionsäure, der β-Amino-α-äthyl-propionsäure und der β-Amino-β-phenyl-propionsäure. Die Verseifung der Estergruppierung der auf diesem Wege zugänglichen β-Phthaloylamino-propionyl-aminosäureester und anschließende Hydrazinolyse gibt die entweder aus zwei β-Aminosäuren oder einer β- und einer α-Aminosäure aufgebauten Dipeptide.
    Additional Material: 8 Tab.
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  • 41
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 119-124 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The structure of (i) NaHg(CN)2(Cl)(H2O), (ii) NaHg(CN)2(Br)(H2O), (iii) NaHg(CN)2(CNS)(H2O), (iv) KHg(CN)2(Br) and (v) KHg(CN)2(CNS) has been studied by infrared spectroscopy. The structure of the anions of I, III and V complexes have been derived on the basis of characteristic absorption frequencies and other known properties and of II and IV on the basis of analogy as the CN groups in these complexes are infrared inactive. CN in these anions are linked as cyanide groups and SCN as isothiocyanate group in V. In III SCN is present both as thiocyanate and isothiocyanate group. III is monomeric with water as a coordinating group. In I and II water is not expected to be a ligand to Hg. Anions of I, II, IV and V are predominantly dimeric with CN as bridging group in the first three and SCN in V.
    Additional Material: 1 Ill.
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  • 42
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 142-146 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über eine einfache und verallgemeinerungsfähige Synthese von Derivaten des Thiapyrons-(2) berichtet. Die Darstellung gelingt durch Umsetzung der β-Mercaptoverbindungen α, β-ungesättigter Carbonsäureester mit monosubstituierten Malonylchloriden.
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  • 43
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    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 177-181 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird gezeigt, daß für N-Acyl-oxazolidine, -1,3-tetrahydrooxazine, -1,3-hexahydrooxazepine, 2-Alkyl-Δ2-thiazoline und 2-Alkyl-Δ2-thiazine Absorptionen im Bereich zwischen 900 und 1000 cm-1 charakteristisch sind. Diese Verbindungen wurden außerdem gaschromatographisch untersucht.
    Additional Material: 5 Ill.
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  • 44
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 199-206 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über Untersuchungen des Verlaufs der Oxydation bei geradkettigen Monoolefinen am Modell Dodecen-1 berichtet, insbesondere über den stimulierenden Einfluß eines Zusatzes von Ozon zum Oxydationsgas auf den Reaktionsablauf.
    Additional Material: 9 Ill.
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  • 45
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 246-252 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Interaction of the 1:1 Th-EDTA diaquo chelate with lactic, mandelic, o-hydroxy naphthoic acids has been investigated by the potentiometric technique. Formation of the mixed ligand chelate derivatives was indicated above pH 5.5. Equilibrium constants of the reactions have been determined.
    Additional Material: 3 Ill.
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  • 46
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 262-265 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method for the analysis of microgram quantities of chloride and sulfate in nickel and nickel nitrate is given. The reliability of the method has been shown by a quantitative recovery of added chloride and sulfate from a solution of nickel nitrate. The method is being applied for the determination of these impurities in electrodeposited nickel. Methods are also given for the determination of boron and sulfide, found as impurities, in the electrodeposited nickel.
    Additional Material: 1 Tab.
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  • 47
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 289-294 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Visible absorption spectra of Nickel (II) sulphate and various aliphatic amines were analysed, in order to extract information regarding each of amine Nickel (II) complex. The presence of six different complexes i.e., mono, di, tri, tetra, penta and hexamines have been indicated by the shift of absorption maxima for these. The energy changes of complexes due to exchange of water ligands with amines have been calculated and an interpretation is offered for this shift in the observed position of absorption maxima.
    Additional Material: 4 Tab.
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  • 48
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 301-304 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A study of the physicochemical properties like refractive index, spectrophotometry, conductivity and pH measurements of a series of mixed solutions of uranyl nitrate and mercurous nitrate have shown the existence of two complexes in solution in the (1:1) and (1:2) molecular ratios respectively viz. \documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{*{20}c} {{\rm UO}_2 \left({{\rm NO}_3 } \right)_2 \cdot {\rm Hg}_2 \left({{\rm NO}_3 } \right)_2,} \hfill & {\left({\rm i} \right)} \hfill \\ {{\rm UO}_2 \left({{\rm NO}_3 } \right)_2 \cdot 2{\rm Hg}_2 \left({{\rm NO}_3 } \right)_2,} \hfill & {\left({{\rm ii}} \right)} \hfill \end{array} $$\end{document}Both the above mentioned compounds have been detected only in the solution by the breaks in the usual curves when various properties like conductivity, refractive index, spectrophotometry and pH were plotted against the m.l. of mercuric nitrate (M/10) added to a fixed volume of uranyl nitrate (M/10).
    Additional Material: 3 Ill.
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  • 49
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 358-361 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A rapid amperometric method for the determination of vanadium (V) has been described which involves titration of vanadium (V) as sodium orthovanadate against copper sulphate solution at Ede = - 0.20 V (vs S.C.E.). The accuracy and reproducability of the method is excellent particularly at higher temperature i.e. at 60°C. The method permits the determination of vanadium (V) down to 0.2 mM with an accuracy 1.0%).
    Additional Material: 1 Ill.
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  • 50
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 366-368 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Three hexaco-ordinated complexes of nickel (II) acetate with ammonia, ethylenediamine and propylenediamine have been prepared. Conductivity measurements indicate the complexes to be non-electrolytes. Molecular weight measurements confirm this. The visible absorption spectrophotometric measurements show a number of bands corresponding to the various permitted transitions of the metal and a discussion of the structure in the light of these transitions is presented.
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  • 51
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 375-377 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some complexes of cerium (IV) sulphate with ammonia and primary aliphatic amines have been prepared. The molecular formulae on the basis of analysis turn out to be Ce(SO4)2 · 4 amine. The complexes behave as electrolytes. The absorption spectra have been recorded and an interpretation is offered for possible transitions.Lanthanides, and cerium in particular are receiving special attention these days. A number of complexes of latter with various ligands and anions have been reported1-5). In the present paper some complexes of cerium (IV) sulphate with ammonia, methyl, ethyl, propyl and butylamine are being presented.
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  • 52
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 369-374 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some substituted sulphonamides have been cyanoethylated and they were subjected to reduction. On hydrolysis with aqueous and alcoholic sodium hydroxide the cyanoethylated sulphonamides gave decyanoethylated products identical to the original sulphonamides.
    Additional Material: 3 Tab.
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  • 53
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 378-381 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Some molecular addition compounds of cobalt (II) oxalate with primary aliphatic amines have been prepared. The general molecular formula on the basis of analysis of constituent elements turn out to be CoC2O4 · RNH2. The formation of compounds is independent of the excess amine concentration. The compounds behave as electrolytes. The molecular weight measurements and VAN'T HOFF factor “i” also confirm this fact.
    Additional Material: 1 Tab.
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  • 54
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 386-390 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of 3-methyl-6,7-benzo-5′(4′)-methyl furano-(2′,3′,1,2) xanthones has been recorded.
    Additional Material: 4 Ill.
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  • 55
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 382-385 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The co-ordination compounds of tripositive iron with nitrogen containing ligands have been found to be of high spin type on the basis of magnetism. The ultraviolet and visible absorption measurements show three bands in the vicinity of 21 400 cm-1, 17 480 cm-1 and 10 650 cm-1.
    Additional Material: 3 Tab.
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  • 56
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 391-396 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 5- und 6-gliedrige 2-Alkyl-cycloalkandione-(1, 3) erhält man durch Umsetzung von Dicarbonsäurehalogeniden mit Carbonsäuren oder von Carbonsäurehalogeniden mit Dicarbonsäuren unter FRIEDEL-CRAFTS-Bedingungen.
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  • 57
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 34-39 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über Darstellung, Analyse und einige Eigenschaften der 2-Methylmercapto-4-methylphenylarsonsäure berichtet. Folgende Reaktionswege führten zum Ziel: (a) 4-Methylanilin → 2-Nitro-4-methylanilin → 2-Nitro-4-methylphenylarsonsäure → 2-Amino-4-methylphenylarsonsäure → 2-Methylmercapto-4-methylphenylarsonsäure; (b) 4-Methylanilin → 2-Amino-6-methylbenzthiazol → 2-Mercapto-4-methylanilin (alkalische Lösung) → 2-Methylmercapto-4-methylanilin → 2-Methylmercapto-4-methylphenylarsonsäure.
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  • 58
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 162-167 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Umsetzung der Acetonketale des Glycerins und des Trimethylolpropans mit Adipinsäureanhydrid liefert Adipinmono- und -diester. Durch nachfolgende Abspaltung der Acetonschutzgruppierungen gelangt man zu Mono-[2, 3-dihydroxypropyl]-adipat, Bis-[2, 3-dihydroxypropyl]-adipat, Mono-[2, 2-dihydroxymethyl-butyl]-adipat, Bis-[2, 2-dihydroxymethyl-butyl]-adipat.
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  • 59
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 20-33 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Das UV-Spektrum des Hexamycins besitzt Maxima bei 336, 356 und 376 nm. Im IR-Spektrum ist die typische Bande der Makrolid-Polyenantibiotika bei 1712 cm-1 enthalten. Der Schmelzpunkt beträgt 120-125°C, das Äquivalentgewicht 824, die Molmasse liegt zwischen 700 und 800. Hexamycin ist in polaren organischen Lösungsmitteln löslich und unlöslich in Wasser und nicht polaren Lösungsmitteln. Lösungen der Substanz verlieren ihre antibiotische Aktivität sowohl durch Erhitzen als auch bei längerem Stehen. Von 21 geprüften Mikroorganismen, vorwiegend Pilze, werden weit über die Hälfte durch 2-32 μg/ml gehemmt. Der Einfluß des Hexamycins auf die Polyphenoloxydase- und Peroxydaseaktivität ist gering. Die Atmung von Saccharomyces cerevisiae Hansen wird durch Hexamycin beträchtlich gemindert.
    Additional Material: 7 Ill.
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  • 60
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 57-68 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Ergebnisse von Gleichgewichts- und kinetischen Messungen der syn-parallelen Cyclisierung diastereomerer 1,2-Aminoalkohole mit Ketonen werden diskutiert. Es wird gezeigt, daß in der Mehrzahl der untersuchten Fälle sterische Faktoren die Gleichgewichtslage und die Reaktionsgeschwindigkeit entscheidend beeinflussen.
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  • 61
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 101-106 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monothio-dibenzoylmethan ist wesentlich reaktionsfähiger als Dibenzoylmethan. Die üblichen Carbonylreagenzien greifen stets zuerst die Thiocarbonylgruppe an. Die Monokondensationsprodukte sind daher schwefelfrei. Wenn sich Bis-kondensationsprodukte bilden, wird zuerst H2S und dann H2O abgespalten. Die Umlagerung der Enol-Form des Monothio-dibenzoylmethans in die Enthiol-Form erfolgt wahrscheinlich direkt und nicht über die Oxo-thioxo-Form.
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  • 62
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 130-136 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: High frequency ultrasonic waves of frequency 1 Mc/s. have been employed to study the decolourization of dilute aqueous solution of crystal violet. The process is irreversible and the kinetic study shows it to be unimolecular one. The deaeration of the solution by nitrogen does not affect the rate of the decolourization. The addition of certain substances such as alcohol, acetone, ether, glycerine, dioxan and allylthiourea inhibits the decolourization to a considerable extent. Oxidation and subsequent destruction of the dye molecule has been found to be the cause of the fading of the dye solution.
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  • 63
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 147-149 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ätherische Titantetramethyllösungen lassen sich einfach durch Einwirkung von Titan(IV)-chlorid auf Methylmagnesiumhalogenidlösungen darstellen. Geeignete Apparaturen werden im folgenden beschrieben.
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  • 64
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 168-176 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2α, 3α- und 2β, 3β- Benzoylimino-cholestan werden durch Natriumjodid in siedendem Aceton zu 2′-Phenyl-(2α, 3α)-oxazolino-[5′, 4′:2, 3]-cholestan bzw. 2′-Phenyl-(2β, 3β)-oxazolino-[5′, 4′:3, 2]-cholestan umgelagert. Mit Bortrifluoridätherat in absolutem Äther bildet 2α, 3α-Benzoylimino-cholestan ebenfalls 2′-Phenyl-(2α, 3α)-oxazolino-[5′, 4′:2, 3]-cholestan. Dagegen erfolgt durch verdünnte Schwefelsäure oder Pikrinsäure in Aceton sowie durch Benzoesäureanhydrid oder Pikrinsäure in Alkohol Ringöffnung zu 2-Hydroxybzw. Alkoxybenzamiden. Die Ringschlußreaktion des diaxialen 2β-Chlor-3α-benzaminocholestan führt mit Natriumhydrogenkarbonat zum Oxazolin, während mit Kaliumhydroxid 2α, 3α-Imino-cholestan entsteht.
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  • 65
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 207-221 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird über Untersuchungen zur Epoxidbildung bei der Oxydation geradkettiger Olefine berichtet. Diese kann durch Zusatz von Ozonid oder Carbonyl auf über 50% des umgesetzten Olefins erhöht werden.
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  • 66
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 192-199 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Carboxyl- bzw. Aldehyd-geschützte Glyoxylsäurederivate wurden für Isonitril-Reaktionen nach UGI eingestzt: Glyoxylsäureamide gaben je nach Reaktionskomponenten Diamide der Aminomalonsäure oder Derivate des Tetrazolyglycins. - Acetale von Glyoxyloylaminosäureamiden (9a, b) wurden aus Dialkoxyessigsäure gewonnen. Das analog aus Dichloressigsäure zugängliche Dichloracetylderivat 9c gab mit Amin ein Aminal, das sich ebenso wie 9a sauer zum entsprechenden 2-Hydroxypiperazin-dion-(3,6) 11a hydrolysieren ließ. - Lävulinsäure konnte mit Amin/Isonitril zu Pyrrolidon-5-carbonsäureamiden cyclisiert Werden.
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  • 67
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    Journal für Praktische Chemie/Chemiker-Zeitung 37 (1968), S. 302-310 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Aminomethylierun von aliphatischen α-Keto-dicarbonsäurediäthylestern und Dicarbonsäurediäthylestern mit mittelständiger Ketofunktion ergab Dimethylaminomethyl-keto-dicarbonsäurediäthylester, deren Hydrochloride thermolytisch in die entsprechenden Methylen-keto-dicarbonsäurediäthylester übergeführt wurden.
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  • 68
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 1-8 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A detailed analytical scheme for the determination of different sulphur compound types in Bakr crude oil distillate fractions up to 350°C was carried out. The quantitative distribution of elemental sulphur, hydrogen sulphide, mercaptans, aliphatic sulphides, aromatic sulphides, reducible and thiophenic sulphur compound types was studied.
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  • 69
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 40-49 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Synthese von Sultamen des p-Xylidins, des 2-Amino-1,3-dimethylbenzols, des 2-Aminoanthrachinons, der p-Aminosalicylsäure und der m-Aminosalicylsäure und einiger ihrer Derivate wird beschrieben. Aus den Butadien-(1,3)-sultamen von zwei Xylidinen konnten die entsprechenden N-Dimethylphenyl-pyrrole hergestellt werden.
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  • 70
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 77-87 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Reaktion von primären langkettigen Alkylhalogeniden mit Alkalicyanat in Dimethylformamid verläuft in Gegenwart stöchiometrischer Wassermengen schnell und vollständig zu den entsprechenden N,N′-Dialkylharnstoffen. Langkettige α,ω-Dihalogenalkane setzen sich analog zu den entsprechenden Polyharnstoffen um. Sekundäre Alkylhalogenide lassen sich mit schlechteren Ausbeuten in verzweigte N,N′-Dialkylharnstoffe überführen. Die als Zwischenprodukte zu erwartenden Alkylisocyanate konnten isoliert werden.
    Additional Material: 5 Tab.
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  • 71
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    Journal für Praktische Chemie/Chemiker-Zeitung 38 (1968), S. 113-118 
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Es wird eine neue Gruppe thiophosphororganischer Verbindungen O,O-Dialkyl-S-(aryldisulfido)-dithiophosphate und deren IR-Spektren berichtet.
    Additional Material: 2 Ill.
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  • 72
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    Helvetica Chimica Acta 51 (1968), S. 153-163 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The occurrence of so-called synchronous 7-centre-fragmentation has been excluded for γ-amino-ketoxime derivatives N—C—C—C—C=N—X. Fragmentation may occur, however, by another route.Reaction rates of the p-toluenesulfonates of (4-quinuclidinyl)-methyl-ketoxime (10b) and (3β-tropanyl)-methyl-ketoxime (14b) in 80% ethanol and the resulting products have been determined. Whereas the latter γ-aminoketoxime underwent quantitative BECKMANN rearrangement to 3β-acetylaminotropane (29), the former yielded 3% fragmentation products besides rearranged 4-acetylamino-quinuclidine (13).A kinetic study reveals that both 10b and 14b react via the rearranged nitrilium ions 12a and 16a, respectively. In the case of the N-(4-quinuclidinyl)-acetonitrilium ion (12a) 5-centre-fragmentation competes with hydration to the amide 13.
    Additional Material: 2 Tab.
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  • 73
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (1) A method is described which allows the elucidation of the structure of cotton cross-linked with formaldehyde. It consists of a permethylation process (5 methylations with dimethyl sulphate and sodium hydroxide in dimethyl sulphoxide, followed by two exchange methylations of the formalised sodium cellulosate with methyl iodide in n-butanol), hydrolysis of the product in 72% sulphuric acid to the respective methylated glucoses, reduction of the mixture of glucoses to the respective sorbitols, blocking of all free hydroxyl groups by acetylation, trifluoroacetylation or formation of trimethylsilyl ethers, and vapour phase chromatographic separation of the derivatives.(2) It is shown that after permethylation practically no free hydroxyl groups can be detected and that scarcely any replacement of methylene or oxymethylene cross-links by methyl groups has taken place. With the exception of losses in filtration of the permethylation product, all stages of the process proceed on an almost quantitative basis.
    Additional Material: 9 Tab.
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  • 74
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction between phenol and trans penta-2,4-dienyl chloride gave trans penta-2,4-dienyl Phenyl ether (I), whereas with a mixture of sorbyl chloride and 1-methylpenta-2,4-dienyl chloride, pure trans, trans hexa-2,4-dienyl phenyl ether (IV) and trans 1-methylpenta-2,4-dienyl phenyl ether (V) were obtained. The ether I gave, on heating in dilute solution at 185°, 4-(penta-2,4-dienyl)-phenol (III) as the main product, and also some 2-(2-vinylallyl)-phenol (II). The ether IV provided, on heating at 165°, in addition to the ortho CLAISEN rearrangement product VI, mainly a mixture consisting of 94% 4-(1-methylpenta-2,4-dienyl)-phenol (VIII) and only 6% 4-(hexa-2,4-dineyl)-phenol(IX). The latter product (IX) was the only para isomer produced on heating ether V, but in addition 22% of the ortho rearrangement product VII was formed.The migrations I → III, IV → VIII, and V → IX, proceeding through a ten membered transition state, are the first [5,5] sigmatropic rearrangements described.
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  • 75
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    Helvetica Chimica Acta 51 (1968), S. 206-210 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A total synthesis of hystrine has been realised with good yield by the introduction of a double link into the piperidine nucleus of synthetic ammodendrine, followed by deacetylation, and purification with the aid of the nitroso derivative.The identity of the synthetic product with authentic hystrine was established by its chromatographic behaviour, by UV.-, IR.- and mass spectra as well as by the properties of its nitroso derivative. Thus the proposed structure of hystrine as 3-(2, 3, 4, 5-tetrahydropyrid-6-yl)-1, 4, 5, 6-tetrahydropyridine (V) is proved.
    Additional Material: 4 Ill.
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  • 76
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The phase diagram of the technical important fusion system pyridine-aluminiumchloride was determined by classical thermo-analysis, proving the existance of a hitherto unknown pyridine-aluminium chloride 2:1 complex.
    Additional Material: 2 Ill.
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  • 77
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    Helvetica Chimica Acta 51 (1968), S. 311-325 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Pachybiose (1) is shown to be 4-O-(3-O-methyl-6-deoxy-β-D-allopyranosyl)-D-oleandrose and asclepobiose (14) 4-O-(3-O-methyl-6-deoxy-β-D-allopyranosyl)-D-cymarose.
    Additional Material: 11 Ill.
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  • 78
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Condensation of the tetrahydropyranyl ether of the α-hydroxyalkyl-thioamides with 3-bromo-4-hydroxy-2-pentanones yields DL-2-(α-hydroxyalkyl)-4-methyl-5-(β-hydroxyethyl)-thiazoles. By oxidation with chromic anhydride 2-hydroxymethyl-4-methyl-5-(β-acetoxyethyl)-thiazole yields the corresponding 2-formyl derivative. The latter compound reacted with GRIGNARD complexes gives the homologous DL-2-(α-hydroxyalkyl)-4-methyl-5-(β-hydroxyethyl)-thiazoles. This is a general method for the synthesis of the thiazole part of the «active aldehydes».2-Acetyl-4-methyl-5-(β-hydroxyethyl)-thiazole is also obtained by chromic oxidation of the suitable methylthiazol-2-yl-carbinol.The condensation of the thioamides obtained from the α-ethoxycarbonyl-nitriles with 3-bromo-5-acetoxy-2-pentanone results in the DL-2-(α-ethoxycarbonyl-alkyl)-4-methyl-5-(β-acetoxyethyl)-thiazoles. The α-hydroxyl function is introduced into the 2-(α-ethoxycarbonyl-alkyl) group by chlorination with sulfuryl chloride and replacement of the introduced chlorine by acetate. The latter compounds are the esters of the thiazole part of the «active α-oxo-carboxylic acids» (e.g. active pyruvate, etc.).The reaction of 2-(α-hydroxyalkyl)-4-methyl-5-(β-hydroxyethyl)-thiazoles and 2-(α-ethoxycarbonyl-α-acetoxy-alkyl)-4-methyl-5-(β-acetoxyethyl)-thiazoles, respectively, with alkyl, alkenyl and aralkyl haloids, or with 2-methyl-4-amino-5-bromomethyl-pyrimidine hydrobromide results in the quaternary thiazolium compounds belonging to the group of the active aldehydes, active α-oxo-carboxylic acids, etc. According to this method 2-hydroxymethyl-thiamine bromide hydro-bromide has been synthesized, which can be considered as the pyrophosphate-free «active formal-dehyde».The 2-α-hydrogen atom in 2-(α-hydroxyalkyl)-thiazolium compounds cannot be replaced by deuterium under conditions similar to those used for the H → D exchange in thiamine.The main peaks in the mass spectra of 2-(α-hydroxyalkyl) substituted thiazoles and thiazolium quaternary salts are listed.
    Additional Material: 2 Tab.
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  • 79
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    Helvetica Chimica Acta 51 (1968), S. 1-16 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The authors propose for the characterization of strepogenic substances of known composition the specific activity, i. e. the number of WOOLLEY units per μmole.Starting from L-leucyl-L-cystinyl-L-leucyl-L-valyl-L-glutamic acid (of very high strepogenine activity, 400 WOOLLEY units per mg, 230 WOOLLEY units per μmole) seven peptides have been synthesized by suppression and/or replacement of amino acid residues. A study of the relation between activity and structure of these peptides shows that: In this group cystine is an indispensable element for activity.This amino acid must either be linked on each side to leucine residues or linked by its carboxyles to leucine, its amino groups being free.From these results, the conception emerges that the strepogenine polypeptides may be characterized by an amino acid (in this group of peptides, cystine) which must be linked to particular amino acid residues. If this conception is correct, there should exist several types of strepogenines depending on the nature of the amino acid essential for their activity.
    Additional Material: 1 Ill.
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  • 80
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    Helvetica Chimica Acta 51 (1968), S. 67-74 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Disazo dyes from 6-amino-1-hydroxy-naphthalene-3-sulfonic acid (J acid) were synthesized by coupling ortho-hydroxy monoazo dyes with different diazonium compounds in acid medium (dyes No 3-14. A second coupling to the ortho position of the amino group was also possible with the copper complexes of o,o' -dihydroxy monoazo dyes from 8-amino-1-hydroxynaphthalene-3,6-disulfonic acid (H acid) dyes No 19-22). This is a reversal of the well known rule that the formation of disazo dyes with aminonaphthol-sulfonic acids is only practicable when an acid coupling is followed by an alkaline one. 5-Amino-1-hydroxy-naphthalene-3-sulfonic acid (M acid), which is said to form no disazo dyes, could be coupled twice with several diazonium compounds to yield disazo dyes (dyes No 24, 26, 27, 29).
    Additional Material: 2 Tab.
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  • 81
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    Helvetica Chimica Acta 51 (1968), S. 94-105 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the reaction of murexide with different divalent metal ions of class A and B have been measured by the temperature-jump-relaxation method. The second-order formation rate constant increases in the sequence Ni2+ 〈 Co2+ 〈 Mn2+ 〈 Zn2+ 〈 Cd2+ ˜ Cu2+ ˜ Ca2+ 〈 Sr2+ 〈 Ba2+ 〈 Pb2+.Thermodynamic data obtained from kinetic and equilibrium studies, respectively, are in good agreement. The results are compared with the characteristic rate constants for H2O-exchange in the inner coordination sphere of these metal ions, which follow the same sequence. The rate constants of the reaction of murexide with various trivalent metal ions, including the lanthanides, are also discussed in terms of current ideas on metal complex formation.
    Additional Material: 1 Ill.
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  • 82
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The total or partial structure determinations of some new components from Dregea abyssinica are reported. The four drebyssogenins (F, G, J and H) are esters of the drevogenins P (7) and D(9) and have the following structures: Drebyssogenin F (5) = 11-O-acetyl-12-O-(α-hydroxyisovaleryl)-drevogenin P, drebyssogenin G (14) = 11-O-acetyl-12-O-isovaleryl-drevogenin D, drebyssogenin J (15) = 11, 12-di-O-acetyl-drevogenin D. Drebyssogenin K is a mixture of K1 (16) and K2 (17), the mono-O-tiglyl and mono-O-isovaleryl derivatives of drevogenin D respectively, with as yet undetermined position of the acyl residues. The drebyssosides 1, 2 and 3 are glycosides of trisaccharides. Drebyssoside 1 (2) is pachybiosyl-cymarosyl-drevogenin A, drebyssoside 2 (3) asclepobiosyl-cymarosyl-drevogenin A and drebyssoside 3 (6) pachybiosyl-cymarosyl-drebyssogenin F. Drebyssoside 4 is a mixture of at least two components and contains the same aglycones and the same sugar units as the drebyssosides 1 and 3, but is different from them. The full structure of the two sugars (drebyssobiose (25) and sugar T (24)) has not been determined; it is only shown that both are disaccharides which contain 3-O-methyl-6-deoxy-allose linked to a 2-deoxyhexose.
    Additional Material: 10 Ill.
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  • 83
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    Helvetica Chimica Acta 51 (1968), S. 526-529 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new organo-metallic titanium-zinc compound [Ti(C5H5)2Cl]2ZnCl2 has been isolated. Its structure has been characterised by means of spectroscopic, susceptibility and dipole measurements.
    Additional Material: 2 Tab.
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  • 84
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    Helvetica Chimica Acta 51 (1968), S. 529-532 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The proton spectrum of furan oriented in the nematic phase of anisoleazophenyl-n-capronate has been analysed. The ratios of the various interproton distances as well as the orientation parameters and the signs of the indirect coupling constants for furan are determined.
    Additional Material: 1 Ill.
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  • 85
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    Helvetica Chimica Acta 51 (1968), S. 569-576 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In earlier publications [1] [2] [3] [4] a pyranoid structure has been proposed for the sugar moiety of imidazoline and imidazolidine derivatives from D-glucosamine. But by NMR.-spectra and periodate oxidation the sugar moiety of these compounds and of similar derivatives from other 2-amino-2-deoxy-sugars is now shown to be of furanoid structure.
    Additional Material: 2 Ill.
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  • 86
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    Helvetica Chimica Acta 51 (1968), S. 598-598 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 87
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    Helvetica Chimica Acta 51 (1968) 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 88
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    Helvetica Chimica Acta 51 (1968), S. 1037-1051 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The present day quantum chemistry is mathematically based on von NEUMANN'S formulation of quantum mechanics and therefore not able to deal correctly with anomal quantum states. A general theory of large molecules and large molecular systems has to be founded on quantum field theory allowing for inequivalent irreducible representations. It is proposed to formulate quantum chemistry in the framework of the B*-algebra of the observables. The paradox of molecular systems having an infinite number of degrees of freedom is discussed, and the possible significance of anomal molecular quantum states for molecular biology is pointed out.
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  • 89
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    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Treatment of 2β-tosyloxy-A-nor-5α-cholestane-5-ol (2) with t-butoxide in t-butanol gave 2α, 5-epoxy-A-nor-5α-cholestane (3) in quantitative yield.When A-nor-5β-cholestane-2α, 5-diol (4) was treated with tosyl chloride in pyridine 2β-chloro-A-nor-5β-cholestane-5-ol (7) and 2α-tosyloxy-A-nor-5β-cholestane-5-ol (8) were obtained. Whereas the chloride 7 was resistant to t-butoxide the tosylate 8 was transformed into an 1 : 1 mixture of 2α, 5-epoxy-5β-cholestane (10) and 2ξ-t-butoxy-A-nor-5β-cholestane-5-ol (11). In 2α-tosyloxy-A-nor-5α-cholestane-5-ol (12) substitution occurred as the only reaction.Both oxetanes 3 and 10 isomerize after heating above 50° and in polar or protic solvents to form A-nor-Δ3(5)-cholestene-2α-ol (6) and -2β-ol (14) respectively. Also, 2, 5-diols are encountered.2α-Ethyl-2β, 2′-epoxy-A-nor-5α-cholestane (23) was synthesized starting from A-nor-5α-cholestane-2-one (17). The intermediates were the ester 16, the diol 18, the hydroxy-tosylate 19 and the chlorhydrin 20. The spirocyclic oxetane 23 was reduced by LiAlH4 in dioxane (not in ether). By chromatography on silica gel 23 was isomerized to the homoallylic alcohol 21 and transformed into 2-methylene-A-nor-5α-cholestane (24) by fragmentation.The IR. and NMR. spectra of the new oxetanes were compared with those of a series of known oxetanes.
    Additional Material: 3 Ill.
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  • 90
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    Helvetica Chimica Acta 51 (1968), S. 1095-1102 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: On décrit la préparation, à partir de la dibromo-2, 5-téréphtalophénone et de quelques-uns de ses dérivés méthylés, par déshydrobromation accompagnée d'une double cyclisation, de la trans-fluorénacène-dione (dioxo-6, 12-dihydro-6, 12-indéno [1, 2-b] fluorène) et de quelques dérivés méthylés. Ces dicétones polycycliques sont colorées en orangé, rouge ou violet, et cuvables. Leur réduction selon WOLFF-KISHNER fournit les hydrocarbures correspondants.
    Additional Material: 1 Tab.
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  • 91
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    Helvetica Chimica Acta 51 (1968), S. 1051-1060 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Magneto-optical rotatory dispersion (MORD.) of saturated aliphatic hydrocarbons can be described very accurately by an equation of the DRUDE type. The two parameters, appearing in such an equation, have been determined from MOR. measurements in the region of 240 to 500 nm by the method of least squares. These parameters show a systematic dependence on the structure of the investigated hydrocarbons. An empirical rule for the approximation of the DRUDE parameters is given which in turn allow the calculation of the VERDET constant for a given structure at any wavelength between 240 and 500 nm.
    Additional Material: 1 Ill.
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  • 92
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    Helvetica Chimica Acta 51 (1968), S. 1108-1119 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 7-Aminocephalosporanic acid or esters thereof are prepared either by intramolecular aminolysis of esters of the antibiotic cephalosporin C or vïa imino-ethers derived from the latter.A simple procedure for the preparation of 7-aminocephalosporanic acid in high yield is described.
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  • 93
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    Helvetica Chimica Acta 51 (1968), S. 1155-1158 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A total synthesis of hog thyrocalcitonin is described. A protected C-terminal tridecapeptide amid (20-32) was coupled with a protected central decapeptide (10-19), and the resulting protected tricosapeptide amide (10-32) was reacted with the N-terminal protected nonapeptide (1-9). After elimination of the protective groups, a free dotriacontapeptide amide was obtained whose physical, chemical and biological behaviour was indistinguishable from that of the natural hormone.
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  • 94
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    Helvetica Chimica Acta 51 (1968), S. 1184-1184 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 95
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of 2-picolylidene-bis-(p-phenylsulfuric acid) disodium salt (I, DCI: ‘sodium picosulfate’) has been realized by two routes. I has been characterized by the usual analytical data and UV., IR. and PMR. spectral properties.
    Additional Material: 2 Ill.
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  • 96
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    Helvetica Chimica Acta 51 (1968), S. 1203-1213 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactivity of hydroxy-indoles under the conditions of the Mannich-reaction has been studied. The electrophilic side-chain enters in each case in a position ortho to the phenolic group. 4-Hydroxy-indole is substituted in the 5-, 5-hydroxy-indole in the 4-, 6-hydroxy-indole in the 7-, and 7-hydroxy-indole probably in the 6-position. The structures of the Mannich bases from 4-, 5- and 6-hydroxy-indole have been confirmed by comparison of the hydroxy-methyl-indoles obtained by reductive desamination with hydroxy-methyl-indoles prepared by unambiguous total synthesis.
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  • 97
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    Helvetica Chimica Acta 51 (1968), S. 1409-1420 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1, 2-Dithioles with sulfur substitutents in position 5 are prepared by reaction of 4-chloro-1, 2-dithiol-3-ones with thiols, sulfinates, dithiocarbamates, or potassium ethylxanthate. Bis-(4-chloro-1, 2-dithiol-3-on-5-yl) sulfide is produced from 4, 5-dichloro-1, 2-dithiol-3-one with sodium thiosulfate and other thiol forming reagents. The 5-alkylthio- and 5-arylthio-1, 2-dithiol-3-ones can be oxidized with peracids to sulfoxides and, partly, to sulfones; the sulfones can also be obtained from sulfinates. 4-Chloro-5-(α-methyl-benzylthio)-1, 2-dithiol-3-one reacts differently with peracetic acid, giving bis-(4-chloro-1, 2-dithiol-3-on-5-yl) disulfide besides 4-chloro-1, 2-dithiol-3-one. With oxalyl chloride, 4-chloro-5-alkylthio-1, 2-dithiol-3-ones form 3, 4-dichloro-dithioliumchlorides, which react with anilines to give 3-phenylimino-4-chloro-5-alkylthio-1, 2-dithioles.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
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  • 98
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Senecio alpinus (L.) SCOP. is very rich in alkaloids. The dried overground parts gave 0,45% crude alkaloid mixture. The main component is seneciphylline (1); small amounts of cristalline jacozine (4) could also be isolated. - Senecio subalpinus KOCH gave 0,368% of crude alkaloid mixture. In contrast to former results only 0,1% of this was present in the form of N-oxides. The bulk was a ca. 1 : 1 mixture of seneciphylline with senecionine (3). - Senecio incanus L. subsp. carniolicus (WILLD) BRä.-BL. gave 0,40% of crude alkaloid mixture; from this some pure seneciphylline could be isolated. - In all three plants the presence of integerrimine (2) and other non-identified alkaloids could be established by thin layer chromatography.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 99
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 51 (1968), S. 1130-1133 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method for the preparation of pure crystalline aldolase (type A) from pupae of Drosophila melanogaster is described.
    Type of Medium: Electronic Resource
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  • 100
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 51 (1968) 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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