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'GC MS' in keywords Facet   section ZfN Section B  [X]
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1983 (1)
1977 (2)
1976 (1)
1Author    Requires cookie*
 Title    Radiation Chemistry of Carbohydrates, X* y-Radiolysis of Crystalline D-Glucose and D-Fructose  
 Abstract    i z d a r o g l u , D. H e n n e b e r g , K . N e u w a l d , G. S c h o m b u r g and C. v o n S o n n t a g In stitu t für Strahlenchemie im M ax-Planck-Institut für Kohlenforschung, Mülheim a. d. Ruhr a-D-Glucose and ß-D-fructose were y-irratiated in the solid (polycrystalline) state at room temperature at doses o f 3.5 • 1020-4 .2 • 1021 eV g-1 (dose rate 1.16 • 1018 eV g_1 min_1). Carbohydrate products containing < 6 carbon atoms were identified and their G-values (in parentheses) measured. Glucose: Dihydroxyacetone (1) (0.05), 3-deoxy-tetrose (2) (O.OI5), l,4-dideoxy-2-pentu-lose (3) (0.05), 2,4-dideoxy-pentose (4) (O.O8 5), 2,4-dideoxy-pentonic acid (5), 2,3-dideoxy-pentos-4-ulose (6) (together 0.03a), threose (7), erythrulose (8), erythrose (9), erythronic acid (10) (together 0.04), l-deoxy-2-pentulose (11) (0.005), 2-deoxy-ribose (12) (0.25), 3-deoxy-pentosulose (13) (0.02), 3,5-dideoxy-hexonic acid (14) (0.02), 2,3-dideoxy-hexonic acid (15) (0.01), arabinose (16) (0.25), ribose (17), ribonic acid (18) (together 0.02), 2-deoxy-2-C-hydroxymethyl-pentonic acid (19) (0.06), 5-deoxy-gluconic acid (20), 2-deoxy-5-keto-glucose (21), 2-deoxy-gluconic acid (22), 2-deoxy-3-keto-glucose (23), 3-deoxy-glucosone (24), 3-deoxy-gluconic acid (25), 3-deoxy-4-keto-glucose (26), 3-deoxy-mannonic acid (27) (together 0.4). Identified but nor measured quantitatively were glucosone (28), 3-keto-glucose (29), 4-keto-glucose (30), 5-keto-glucose (31) and gluconic acid (32). G(H2) = 5.75; G (C02) = 0.7. Fructose: 7-9 (together 0.65), 3-deoxy-pentonic acids (37), 3-deoxy-pentosulose (38) (together 0.3), arabonic acid (39) (0.1), 18 (0.05), 6-deoxy-2,5-hexodiulose (40) (40). Identified but not measured quantitatively were glyceraldehyde (34), butanone-(3)-diol-(l,2) (35) and 2 -and 3-deoxy-hexodiuloses. G(H2) = 4.75, G (C02) = 0.05. Reaction schemes are proposed to account for the form ation of the products. The scission of the hemiacetal bond and of the C-H and C-C bonds next to it appears to be typical for solid state irradiations. The formation of deoxy-compounds is observed both in the solid state and in aqueous solution. The form ation o f dideoxy-compounds is only prominent in the solid state. In polycrystalline fructose a chain reaction is induced leading to 6-deoxy-2,5-hexodiulose (40). 
  Reference    (Z. Naturforsch. 32b, 213—224 [1977]; received October 27 1976) 
  Published    1977 
  Keywords    GC-MS, G-Values, Radical Reactions, Chain Reaction 
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 TEI-XML for    default:Reihe_B/32/ZNB-1977-32b-0213.pdf 
 Identifier    ZNB-1977-32b-0213 
 Volume    32 
2Author    Mibal Dizdaroglu, Klaus Neuwald, ClemensVon SonntagRequires cookie*
 Title    Radiation Chemistry of DNA Model Compounds, IX* Carbohydrate Products in the y-Radiolysis of Thymidine in Aqueous Solution. The Radical-Induced Scission of the N-Glycosidic Bond  
 Abstract    In the y-radiolysis of deoxygenated N20-saturated aqueous solutions of thymidine (10-3 M, room temperature, dose rate 4 • 10 18 eV/g.h., dose 6.7 10 17 -3.3 • 10 18 eV/g) the following products (G-values in parentheses) have been identified: 2,5-dideoxy-pentos-4-ulose (1) (0.01), 2,4-dideoxy-pentodialdose (2) (0.02), 2,4-dideoxy-pentos-3-ulose (3) (0.03), 2,3-dideoxy-pentos-4-ulose (4) (0.01), 2-deoxy-pentos-4-ulose (5) (0.1), 2-deoxy-ribonic acid (6) (0.02) and thymine (8) (< 0.2). In the presence of oxygen (N20/02 80/20 v/v saturated) products 1-4 are absent, G (5) = 0.2, G (6) = 0.07 and G (8) < 0.4. Further-more, 2-deoxy-tetrodialdose (7) which is absent in deoxygenated solution is formed with a G-value of 0.03. Mechanisms are proposed to account for the scission of the N-glycosidic linkage. Product 6 is thought to be due to a primary OH radical attack at C-l' of the sugar moiety, 3 arises from an attack at C-3', 1, 4 and 5 from an attack at C-4', and 2 and 7 from an attack at C-5'. 
  Reference    (Z. Naturforsch. 31b, 227—233 [1976]; received September 24 1975) 
  Published    1976 
  Keywords    Thymidine, Radiolysis, Radical Reactions, GC-MS, DNA Model Compounds 
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 TEI-XML for    default:Reihe_B/31/ZNB-1976-31b-0227.pdf 
 Identifier    ZNB-1976-31b-0227 
 Volume    31 
3Author    Requires cookie*
 Title    Photolysis (A = 185 nm) of Liquid Acetaldehyde Dimethyl Acetal  
 Abstract    H e in z -P e t e r S c h u c h m a n n a n d C l e m e n s v o n S o n n t a g In stitut fü r Strahlenchemie im M ax-Planck-Institut für Kohlenforschung, Mülheim a. d. R uhr Deaerated liquid acetaldehyde dimethyl acetal has been photolyzed at X = 185 nm, and 28 products have been determined. The m ajor ones with their quantum yields are: methanol (0.59), methane (0.26), ethyl methyl ether (0.17), m ethyl vin yl ether (0.16), m ethyl form ate (0.14), ketene dimethyl acetal (0.1), ethane (0.06), hydrogen (0.06), and acetaldehyde (0.06). The m ajor prim ary processes are suggested to be the scission o f the C-OCH3 bonds (homolytic and molecular) and o f the O-CH3 bonds (homolytic). Minor processes are hydrogen elimination reactions and the scission o f the C-CH3 bond. 
  Reference    (Z. Naturforsch. 32b, 205 [1977]; received October 8 1976) 
  Published    1977 
  Keywords    UV, GC-MS, Quantum yields, Radical Reactions, Fragm entation Processes 
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 TEI-XML for    default:Reihe_B/32/ZNB-1977-32b-0205.pdf 
 Identifier    ZNB-1977-32b-0205 
 Volume    32 
4Author    H. Schildknecht, B. Weber, K. DettnerRequires cookie*
 Title    Über Arthropodenabwehrstoffe, LXV Die Chemische Ökologie des Grundschwimmers Laccophilus minutus On Arthropode Defensive Compounds, LXV The Chemical Ecology of the Water Beetle Laccophilus minutus  
 Abstract    According to a GC-MS analysis of methylated extracts the abdominal tips of the water beetle Laccophilus minutus (Dytiscidae) contain four ß-hydroxyalkanoic acids. On the basis of MS and GC data another compound was assigned the structure of 6-octenoic acid. The same /S-hydroxyalkanoic acids, and in addition, traces of ^-hydroxyheptanoic acids were identified in dissected pygidial defensive glands after trimethylsilylation. Methyl 3,4-dihydroxyphenylacetate was recognized as a further main component in the pygidial gland secretion from the mass spectrum of its TMSi ether. The Laccophilinae occupy unique position among all the dytiscide subfamilies because they are the only water beetles which store yS-hydroxyalkanoic acids in their pygidial glands. On the other hand the dytiscides appear to form a monophyletic group which is supported by the occurrence of methyl 3,4-dihydroxyphenylacetate. This class of compound is also commonly encountered in the other dytiscide subfamilies. 
  Reference    Z. Naturforsch. 38b, 1678—1685 (1983); eingegangen am 7. Juli 1983 
  Published    1983 
  Keywords    Arthropode Defensive Compounds, ß-Hydroxyalkanoic Acids, Methyl 3, 4-dihydroxyphenylacetate, GC-MS, Chemical Ecology 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-1678.pdf 
 Identifier    ZNB-1983-38b-1678 
 Volume    38