scholarly journals Hydrogenative Cleavage of Azo Compounds Catalyzed by Commercial Zinc Dust Using Ammonium Acetate.

ChemInform ◽  
2004 ◽  
Vol 35 (18) ◽  
Author(s):  
G. R. Srinivasa ◽  
K. Abiraj ◽  
D. Channe Gowda
2002 ◽  
Vol 2002 (8) ◽  
pp. 384-385 ◽  
Author(s):  
Shankare Gowda ◽  
K. Abiraj ◽  
D. Channe Gowda

Azo compounds are reductively cleaved to amine/s at reflux temperature within 15 min by employing less expensive commercial zinc dust and hydrazinium monoformate, a new hydrogen donor for catalytic transfer hydrogenation.


1979 ◽  
Vol 32 (6) ◽  
pp. 1281 ◽  
Author(s):  
DJ Bell ◽  
IR Brown ◽  
R Cocks ◽  
RF Evans ◽  
GA Macfarlane ◽  
...  

2,3,5,6-Tetramethyl-, tetraethyl- and tetraisopropyl-pyrazines were obtained by fusion of ammonium acetate with the appropriate acyloin or reduction of the α,α'-diketone dioxime with zinc dust and alkali. Photolysis of a cyclohexane solution of tetraisopropylpyrazine led inter alia to formation of bicyclohexyl. Photolysis of an aqueous solution of tetramethylpyrazine containing sodium borohydride caused complete reduction of the pyrazine ring to the hexahydro stage. The high-resolution mass spectra of these pyrazines are discussed and explained in the light of deuterium labelling and metastable defocusing information.


Author(s):  
A.-M. Ladhoff ◽  
B.J. Thiele ◽  
Ch. Coutelle ◽  
S. Rosenthal

The suggested precursor-product relationship between the nuclear pre-mRNA and the cytoplasmic mRNA has created increased interest also in the structure of these RNA species. Previously we have been published electron micrographs of individual pre-mRNA molecules from erythroid cells. An intersting observation was the appearance of a contour, probably corresponding to higher ordered structures, on one end of 10 % of the pre-mRNA molecules from erythroid rabbit bone marrow cells (Fig. 1A). A virtual similar contour was observed in molecules of 9S globin mRNA from rabbit reticulocytes (Fig. 1B). A structural transformation in a linear contour occurs if the RNA is heated for 10 min to 90°C in the presence of 80 % formamide. This structural transformation is reversible when the denatured RNA is precipitated and redissolved in 0.2 M ammonium acetate.


Author(s):  
N. H. Sarkar ◽  
Dan H. Moore

Mouse mammary tumor virus (MTV) is believed to contain about 0.8% single stranded ribonucleic acid (RNA). This value of RNA content was estimated on a dry weight basis. The subject of this report is an attempt to visualize the RNA molecules of MTV particles.MTV particles were isolated from RIII mouse (tumor incidence approximately 80%) milk according to the method described by Lyons and Moore. Purified virions from 5 ml of milk were finally suspended in 0.2 ml of PBS, pH 7.4 and was mixed with an equal volume of pronase (5 mg/ml). This mixture was incubated at 37°C for an hour. RNA was extracted three times using freshly prepared cold phenol. It was then treated three times with cold ethyl ether to remove any trace of phenol. The RNA thus extracted was divided into two parts. One part was diluted four fold with 8M urea to avoid aggregation of the molecules. The other part was left untreated. Both samples were then mixed with an equal volume of 1M ammonium acetate, adjusted to pH 8.0 with NH3 containing chymotrypsin at a concentration of 0.01%.


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