Menschliches Blut enthait die bisher unbekannte 3-Carboxy-4-methyl-5-(l-oxopropyl)-2-furanpropansaure (4) und die 3-Carboxy-4-methyl-5-(l-hydroxypropyl)-2-furanpropansaure (5). Ihre aus Massenspektren abgeleiteten Strukturen wurden durch Synthese sichergestellt: 3-Oxoadipinsaure-dimethylester (11) wurde mit Hydroxyaceton in Gegenwart von Zinkchlorid zu 3-Methoxycarbonyl-4-methyl-2-furanpropans~ure-methylester (12) kondensiert. Nachfolgende Acylierung von 12 mit Propionsaureanhydrid ergab 3-Methoxycarbonyl-4-methyl-5-(l-oxopropyl)-2-furanpropansaure-methylester (6), woraus durch Natrium-tetrahydrido-borat-Reduktion 3-Methoxycarbonyl-4-methyl-5-(l-hydroxypropyl)-2-furanpropansaure-methylester (7) erhalten wurde. Identification, Structure Elucidation, and Synthesis of Previously Unknown Urofuranic Acids in Human BloodHuman blood contains the previously unknown 3-carboxy-4-methyl-5-(l-oxopropyl)-2-furanpropanoic acid (4) and 3-carboxy-4-methyl-5-( l-hydroxypropyl)-2-furanpropanoic acid (5). Their structures (deduced from mass spectra) were proved by synthesis: 3-oxoadipic acid dimethyl ester (11) was condensed with hydroxyacetone to 3-methoxycarbonyl-4-methyl-2-furanpropanoic acid methyl ester (12) in the precence of zinc chloride. By acylation of 12 with propanoic anhydride the 3-methoxycarbonyl-4-methyl-5-(l-oxopropyl)-2-furanpropanoic acid methyl ester (6) was obtained. By reduction of 6 with sodium tetrahydridoborate the 3-methoxycarbonyl-4-methyl-5-(lhydroxypropyl)-2-furanpropanoic acid methyl ester (7) was synthesized.
Die aus menschlichem Blutplasma isolierte Carbonsaurenfraktion wurde nach Methylierung saulenchromatographisch aufgetrennt und dann mit Hilfe der Kombination Glaskapillargaschromatographie-Massenspektrometrie untersucht. Neben bisher als Blutinhaltsstoffe unbekannten gesattigten Dicarbonsauren wurden 5-Decindisaure, Propyl-und Pentylurofuransauren, wund y-Oxosauren sowie 2und 3-Hydroxysauren entdeckt. Carboxylic Acids in Human Blood")The carboxylic acidic fraction isolated from human blood plasma was separated by column chromatography after methylation and then investigated with the aid of combined glass capillary gas chromatography-mass spectrometry. Besides some saturated dicarboxylic acids hitherto unknown to occur in blood, 5-decynedioic acid, propyl-and pentylurofuroic acid, wand y-0x0 acids as well as 2-and 3-hydroxy acids were detected.
The insecticide propoxur (2-isopropoxyphenyl-N-methylcarbamate) acts by blocking cholinesterase. This inhibition is fast and, unlike that brought about by organophosphorus compounds, reversible. The toxicity of propoxur to man is stated to be low compared with that of parathion. Only a small number of fatal intoxications have been published; at the Würzburg University Institute of Legal Medicine eight cases have been observed since 1978. In seven cases death occurred after deliberate oral ingestion of solutions of propoxur with suicidal intent, while in the other, intoxication was accidental, following inhalation of an aerosol containing propoxur. Organs and body fluids were investigated toxicologically and histologically. The results are presented and discussed. Special attention is paid to the combination of propoxur and alcohol.
for the synthesis of I ,4-dihydronaphthalene-cis-l,4-diol (2)[51, racemic epoxytetrahydronaphthalenediol (4)[61, and synnaphthalene 1,2 : 3,4-dioxide (5)['1, which should also be applicable to other systems.The Diels-Alder reaction of trans,trans-l,4-butadienylene diacetate with benzyne (from o-benzenediazoniumcarboxylate)gives (1) (53 %, m.p. 88°C) (see Table 1 for NMR data). Compound (1) is readily deacetylated to (2)15' (88 %, m. p.105°C) with Na2C03 in methanol. cis-Hydroxylation of ( I ) with hydrogen peroxide and catalytic amounts of osmium tetroxide leads stereospecifically to ( 3 a) (60 %, m. p. 156°C) which undergoes facile transformation into the racemic monotosylate (3 b ) (75 %, m. p. 141 "C) with tosyl chloride in dry pyridine. On stirring with N a 2 C 0 3 in methanol, ( 3 b ) affords the racemicepoxy-diol (4)I6l (90 %, viscous oil) almost quantitatively. This product has the stereochemistry characteristic for carcinogens of this type. The dimesylate ( 3 c) (82 %, m. p.157°C) also readily accessible from ( 3 a) specifically forms the
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