mixed melting point
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1974 ◽  
Vol 144 (2) ◽  
pp. 303-310 ◽  
Author(s):  
M P Heenan ◽  
J N Smith

Metabolites isolated from houseflies dosed with 1-napththol or p-nitrophenol were identified as the phosphate and glucose phosphate conjugates of these phenols by titrations, hydrolysis, ionophoresis, i.r. spectra and mixed melting point. [3H]Carbaryl (1-naphthyl N-methylcarbamate) was metabolized by houseflies, blowflies and grass grubs to water-soluble metabolites which had chromatographic and ionophoretic behaviour similar to those of the conjugates of 1-naphthol with glucose, sulphate, phosphate and glucose 6-phosphate.



1970 ◽  
Vol 119 (1) ◽  
pp. 17-19 ◽  
Author(s):  
Richard L. Katzman ◽  
Elwira Lisowska ◽  
Roger W. Jeanloz

1. d-Arabinose, an extremely rare sugar in the animal kingdom, was isolated from a complex acidic polysaccharide obtained from the connective tissue of the sponge Hippospongia gossypina. A crystalline derivative of arabinose, the 1-benzyl-1-phenylhydrazone, was prepared and characterized by its melting point, optical rotation, and mixed melting point with authentic d- and l-enantiomers. 2. The distribution of arabinose within the animal kingdom is discussed, and a biological role is proposed for the spongonucleotides.



1962 ◽  
Vol 35 (3) ◽  
pp. 659-660 ◽  
Author(s):  
Teresa Gessner

Abstract Klebanski and Fomina have reported on the action of alkali on tetraethylthiuram disulfide (TETD). They suggested the following equation for the reaction: (see PDF for diagram) This equation is based in part on a premise that TETM is one of the reaction products; we feel this premise is incorrect. As partial evidence for their proposed reaction scheme, Klebanski and Fomina claim the isolation of tetraethylthiurammonosulfide (TETM) from the reaction products. They give both the analysis figures and the melting point of the isolated substance. The melting point quoted by them is 64–65°. The melting point of TETM is, however, 28–33°. We have attempted the isolation of the substance reported by Klebanski and Fomina, and have repeated their experiment according to the published instructions. The only water-insoluble material which we were able to isolate, after 8 hours reaction with 2% aqueous sodium hydroxide, was unreacted TETD (73% of the starting material). The material isolated had a melting point of 68.5–70°, mixed melting point with TETD was 68.5–70°, the nitrogen and sulfur content was: %N 9.38, %S 42.82. Recrystallized from ether the substance melted at 70°, and analyzed as: %N 9.48, %S 43.05, mol. wt. 297; TETD requires; %N 9.53, %S 42.93, mol. wt. 296, m. pt. 70°.



1957 ◽  
Vol 35 (12) ◽  
pp. 1434-1437 ◽  
Author(s):  
Mary J. Chisholm ◽  
C. Y. Hopkins

A sample of body fat of the Canadian musk ox (Ovibosmoschatus subsp.) was converted to methyl esters and distilled. The fraction containing esters of C17 acids was crystallized fractionally at low temperature and two straight-chain C17 acids were isolated. n-Heptadecanoic acid was identified by analysis, by mixed melting point of the acid and two derivatives with authentic samples, and by its X-ray diffraction pattern. 9-Heptadecenoic acid was identified by analysis, by mixed melting point of two derivatives with authentic samples, and by oxidative cleavage. It is estimated that the fat contained 1.7% of n-heptadecanoic acid and 0.9% of cis-9-heptadecenoic acid, based on the total fatty acids. Although there was an appreciable content of trans acids in the fat, the heptadecenoic acid was found to contain little or none of the trans form.



1957 ◽  
Vol 35 (12) ◽  
pp. 1123-1133 ◽  
Author(s):  
Donald Fraser ◽  
C. C. Lucas

In 1955, the occurrence of a hitherto unreported ninhydrin-positive substance in the urine and plasma of infants suffering from hypophosphatasia was described. Evidence published at that time and subsequently suggested that the material might be phosphorylethanolamine, but the isolation and unequivocal identification of the substance has not been reported.The present paper describes the isolation of a small amount of the previously unidentified compound from the urine of the heterozygous father of a seriously affected infant. The melting point, mixed melting point, X-ray diffraction pattern, infrared absorption spectrum, and N: P ratio establish the identity of the substance to be phosphorylethanolamine. Proof that this compound occurs in hypophosphatasia provides a logical basis for further study of the metabolic importance of this substance.



1957 ◽  
Vol 35 (1) ◽  
pp. 1123-1133
Author(s):  
Donald Fraser ◽  
C. C. Lucas

In 1955, the occurrence of a hitherto unreported ninhydrin-positive substance in the urine and plasma of infants suffering from hypophosphatasia was described. Evidence published at that time and subsequently suggested that the material might be phosphorylethanolamine, but the isolation and unequivocal identification of the substance has not been reported.The present paper describes the isolation of a small amount of the previously unidentified compound from the urine of the heterozygous father of a seriously affected infant. The melting point, mixed melting point, X-ray diffraction pattern, infrared absorption spectrum, and N: P ratio establish the identity of the substance to be phosphorylethanolamine. Proof that this compound occurs in hypophosphatasia provides a logical basis for further study of the metabolic importance of this substance.



1934 ◽  
Vol 56 (11) ◽  
pp. 2489-2490 ◽  
Author(s):  
H. A. Shonle ◽  
E. C. Kleiderer


1933 ◽  
Vol 8 (2) ◽  
pp. 180-197 ◽  
Author(s):  
J. S. L. Browne

A crystalline oestrogenic hormone has been isolated from human placenta. This substance shows a melting point of 274 °C. (uncorrected). The carbon-hydrogen analysis gives: carbon, 74.8%; hydrogen, 8.8%. The mixed melting point with theelol shows no lowering. The substance differs physiologically from previously isolated female sex hormones. It is relatively inactive on the adult ovariectomized albino rat. The dose required is 16 γ as compared with 1.5 γ for theelol. It is, however, effective on the immature intact rat, 21 days old, in a dose of 1.2 γ. This is the same as theelol. On the immature castrate, the dose of the placental crystals is 10 γ, that for theelol is 3 γ. The presence of the ovary is believed to be the factor in the dosage ratio between adult spayed and normal intact animals. Transplantation of immature ovaries into immature or adult castrates, even though it does not render them cyclic, causes the weight of the placental crystals needed for an effect to fall to the immature intact dose.



1932 ◽  
Vol 7 (3) ◽  
pp. 285-292 ◽  
Author(s):  
J. Ansel Anderson

Khapli wheat leaves contain a very small quantity of a trihydroxydimethoxyflavone, tricin. Marquis yields a trace of the same compound. These two varieties also contain water-soluble coloring matters which are apparently glucosides of tricin or of a closely related compound. Dyeing tests carried out with six other wheat varieties indicate that all contain essentially the same coloring matters.Methylation of tricin and hydrolysis of the resulting O-trimethyltricin yielded 3,4,5-trimethoxybenzoic acid and 2-hydroxy-4,6-dimethoxyacetophenone. It was therefore assumed that tricetin, the pentahydroxyflavone derived from tricin, was 5,7,3′,4′,5′-pentahydroxyflavone. This was synthesized from 3,4,5-trimethoxybenzoic acid and phloracetophenone by the Allan-Robinson method. Mixed melting-point determinations showed that its O-pentamethyl and O-penta-acetyl derivatives are identical with the corresponding derivatives of tricetin. The dyeing properties and color reactions of synthetic and natural tricetin are identical and are in fair agreement with those described by Badhwar, Kang and Ventkataraman (3, p. 1111) who recently reported the synthesis of the same compound.



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