FlufenaminsLure ist UV-spektroskopisch bestimmbar. Empfindlicher und spezifischer ist der fluorimetrische Nachweis nach Uberfiihrung in Heterocyclen. Mit Formaldehyd wird l-(m-Trifluormethyl-phenyl)-4-oxo-1,2-dihy~o-3,l,4-benzoxazin, mit konz. H,SO, (4) (2)-Trifluormethylacridon gebildet, die sich zur Analyse (< 1 y ) verwenden lassen. Der EinfluB von Substituenten wird am Beispiel von 16 Verbindungen untersucht. Bestimmungen aus biologischem Material werden angegeben.
a decided commercial success, and there may be many other applications such as the one suggested in this paper.The very low pressures recorded in this paper are a tribute to the excellent construction of the apparatus and also to the pumping capacity of the large diffusion pump which was used. A question arises as to whether the results obtained at 0.05 microns are any different than those that would be obtained at 5 or even 50 microns. This point is of importance because the 0.05 mieron pressure would be very difficult to maintain on a commercial scale.The use of a vacuum in distillation has two main purposes: to protect the metal or metals from oxidation and to increase the rate of evaporation. Pidgeon reported that in the ferrosilicon-dolomite process no improvement in yield was noted at two microns as compared with 100-200 microns. St. Clair and Spendlove of the U. S. Bureau of Mines have reported careful determinations on the rate of evaporation of zinc versus residual gas pressures; one series of tests showed no increase in rate below pressures of 100 microns. A second series of tests are not as conclusive; there seems to be some improvement below 100 microns but the data are scattered. P. C. Carman writing in the 1948 Transactions of the Faraday Society states that in the distillation of liquids or the evaporation of solids the following equation gives the relation between rate of evaporation and the residual gas pressure when P is less than r W= Wo(l -P)where W = rate of evaporation, Wo = the maximum rate, P = the pressure above the liquid or solid, and ~ is the saturation vapor pressure of the solid or liquid.Taking Run No. 4 as an example, at 600~ the vapor pressure of magnesium would be close to 880 microns. The distillation rate under a residual gas pressure of 0.05 microns according to the above equation would be 99.9944 per cent of the maximum rate. At a residual gas pressure of 5 microns the measured rate would be 99.44 per cent maximum, and at 50 microns it would be 94.4 per eent maximum.This loss of 5.6 per cent in the evaporation rate resulting from operation at 50 microns rather than 0.0.5 microns is not very serious as it could be compensated for by a temperature increase of 2~ At lower temperatures the difference in evaporating rates between operating pressure of 0.05 and 50 mierons would be greater; at higher temperatures it would be less.R. R. ROGERS AND G. E. VIENS: Dr. Sehleehten's remarks deal largely with the effect of pressure on evaporation rate and yield. Since only one pressure was used in the work which we have reported, our paper does not eontain any conclusions with regard to the effect of pressure. We were concerned particularly with the efficiency with which the alloying metals could be removed from the magnesium, i.e. with the efficiency with whieh the magnesium could be refined. We also wished to determine the lowest temperature at which the process could be operated satisfactorily. Obviously the success of the process would be determined to a considerable extent by these two...
1-Methylhydantoin (3) konnte als renaler Metabolit von Dupracetam (I.N.N., prop.), 1,2-Bis-(2-oxo-pyrrolidinessigsaure)hydrazid (l), bei Hunden identifiziert werden. Die Strukturzuordnung erfolgte mittels MS, NMR und IR sowie Vergleich mit authentischer Substanz. 3 tritt auch bei Ratten nach 1-Applikation intcrmediar auf. In Hinblick auf sein nootropes Wirkungsprofil ist 3 nicht so interessant wie Dupracetam. 1-Methylhydnntoio, an Unexpected Metabolite of the Nootropic Substance Dapracetam1-Methylhydantoin (3) was found to be a renal metabolite of dupracetam, 1,2-bis-(2-oxopyrrolidi-nylacety1)hydrazine (l), in dogs. Structural assignment was made by MS, NMR, IR and comparison with authentic material. Compound 3 was also found in rats as an intermediate. The nootropic profile of 3 is less interesting than that of 1. Die Substanz Dupracetam (I.N.N., prop.), 1,2-Bis-(2-oxo-pyrrolidinessigsaure)hydrazid (l)'), erwies sich bei der pharmakologischeh Priifung als nootrop wirksam". Diese und iihnliche Substanzen sowie deren Hydrolyse-und potenticlle Metabolisierungsprodukte wurden kurzlich von uns untersucht'). Im Rahmen der Testung der Verbindung 1 an Versuchstieren und Menschen wurde auch nach Metaboliten gesucht. Die vorliegende Arbeit sol1 die Isolierung, Identifiziemng und pharmakologische Priifung eines ungewahnlichen Metaboliten beschreiben. oxmmi-s u z . m
Determination of DequaPnium Compounds in Biological MaterialThe fluorimetric determination of dequalinium salts in biological material is investigated. After oral or intravenous application to rats and dogs only traces of unchanged dequalinium salts (chloride and acetate) are renal excreted. In addition the urine contains minor quantities of a metabolite, possibly the 2.2'-dicarboxylic acid derivative. Therefore no bactericide effect of the urine is to be expected after application of therapeutic doses of dequalinium acetate or chloride itself, but possibly by the reaction of unidentified metabolites of dequalinium.Von zahlreichen Polymethylen-bis(4-aminochinaldinium)-Derivaten1) 2, envies sich die Decamethylenverbindug (I) als besonders stark antimikrobiell wirksam3). Dequaliniumsalze, I, haben ein au5ergewohnlich breites Wirkungsspektrum. Wghrend
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