On the Chemistry of Ingenol, Va. Preparation of Tritium-Labeled 3-O-Tetradecanoylingenol (|20-3H]-3-TI)
نویسنده
چکیده
Tritium-labeling o f the ingenol monoester 3-O-tetradecanoylingenol (3-TI), the prototype tumor promoter o f the ingenane type diterpene esters, is described. The preparation starts with oxidation o f 3-TI by manganese dioxide to yield 3-TI-20-aldehyde which is reduced by [3H]sodium borohydride in the presence o f equimolar amounts o f cerium trichloride hexahydrate to give [20-3H]-3-TI. The labeled promoter is obtained in 42% overall yield with a specific ra dioactivity o f 15.8 Ci/mmol.
منابع مشابه
Metabolism of 1-3H-ethanol by isolated liver cells. Time-course of the transfer of tritium from R,S-1-3H-ethanol to lactate and beta-hydroxybutyrate.
Parenchymal cells isolated from the liver of 24 h fasted rats were incubated with 65 mM R,S-1-3H -ethanol plus 3 mM pyruvate as substrates in the absence and presence of 1.7 mM 4-methylpyrazole. Metabolite levels and the time-course of the transfer of tritum from ethanol to lactate and beta-hydroxybutyrate was measured during the first 15 min of ethanol metabolism. The time-course of the loss o...
متن کاملMetabolism of tritium-labeled 12-O-tetradecanoylphorbol-13-acetate by cells in culture.
The metabolism of [20-3H]-12-O-tetradecanoylphorbol-13-acetate ([3H]TPA) was studied in human and hamster cell cultures. Within 2 to 3 days after its addition to growing or confluent cultures of hamster embryo fibroblasts, no unchanged [3H]TPA remained in the medium as determined by thin-layer chromatography of the chloroform phase obtained by extraction of the medium with chloroform:methanol:H...
متن کاملBiochemical synthesis of stereospecifically hydrogen labeled compounds on a preparative scale, VI1-3 Synthesis of further substrates of NAD(P)-linked dehydrogenases of high specific tritium content.
The preparation of (R) and (S) [2(-3)H]lactate as well as (S) [2(-3)H] glutamate via the coupled exchange reaction catalyzed by NAD linked dehydrogenases and NADH: lipoamide oxidoreductase (diaphorase) is described. The specific radioactivity of the hydrogen ions of the 3HOH/H2O can be obtained in the substrates (100% exchange) if equilibrium isotope effects are disregarded. By the exchange pro...
متن کاملUse of 3H and 14C double-labeled glucose to assess in vivo pathways of amino acid biosynthesis in Escherichia coli.
3H and 14C tracing data concerning amino acid biosynthetic pathways in Escherichia coli K12 are presented. Thirteen acidic and neutral amino acids were isolated from protein hydrolysates of wild type E. coli K12 grown aerobically or anaerobically in the presence of [U-14C]glucose together with [1-3H]glucose, [3-3H]glucose, [4-3H]glucose, or [6-3H]glucose. The observed 3H/14C counts of the amino...
متن کاملRapid changes in hepatocyte phosphoinositides induced by vasopressin.
Vasopressin stimulated a 40% decrease in [32P]phosphatidylinositol 4,5-bisphosphate and a 15% decrease in [32P]phosphatidylinositol within 30 s of addition to hepatocytes prelabeled for 60 min with 32P. In hepatocytes prelabeled with [3H]inositol for 60 min, vasopressin produced 20% breakdown of phosphatidylinositol and 33% breakdown of phosphatidylinositol 4,5-bisphosphate within 30 s. There w...
متن کامل