Production and magic numbers of large hydrated anion clusters X-(H2O)n=0-59(X = hydroxyl, oxygen atom or molecule, and ozone) under thermal conditions [Erratum to document cited in CA113(24):218631e]

1990 ◽  
Vol 94 (26) ◽  
pp. 8974-8974 ◽  
Author(s):  
X. Yang ◽  
A. W. Castleman
Keyword(s):  
Oxygen Atom ◽  
Thermal Conditions ◽  
Magic Numbers ◽  
Hydroxyl Oxygen ◽  
Hydroxyl Oxygen Atom ◽  
Anion Clusters ◽  
Hydrated Anion

scholarly journals X-ray structure of cytidine-5′-O-dimethylphosphate. Novel stacking between the ribosyl O(2′) hydroxyl oxygen atom and the base

1984 ◽  
Vol 12 (17) ◽  
pp. 6813-6825 ◽  
Author(s):  
Richard G. Brennan ◽  
Norman S. Kondo ◽  
Muttaiya Sundaralingam
Keyword(s):  
Oxygen Atom ◽  
X Ray ◽  
Hydroxyl Oxygen ◽  
Hydroxyl Oxygen Atom

More Magic Numbers in Titanium-Carbon Anion Clusters: Can This Be Explained by Any Structural Growth Pattern?

2001 ◽  
Vol 18 (12) ◽  
pp. 1582-1585 ◽  
Author(s):  
Zhai Hua-Jin ◽  
Liu Bing-Chen ◽  
Zhou Zheng-Wen ◽  
Zhou Ru-Fang ◽  
Ni Guo-Quan ◽  
...  
Keyword(s):  
Growth Pattern ◽  
Magic Numbers ◽  
Anion Clusters ◽  
Structural Growth

MYCOCHRYSONE: II. CARBON SKELETON, PRINCIPAL CHROMOPHORE, AND OXYGEN FUNCTIONS

1959 ◽  
Vol 37 (11) ◽  
pp. 1881-1887 ◽  
Author(s):  
G. Read ◽  
L. C. Vining
Keyword(s):  
Oxygen Atom ◽  
Methyl Ether ◽  
Infrared Spectra ◽  
Carbon Skeleton ◽  
Hydroxyl Oxygen ◽  
Elemental Analyses

A mono-and di-methyl ether and two diacetates of mycochrysone have been prepared. Elemental analyses of these derivatives and of the purified pigment itself are consistent with a revised C20H12O7 formula for mycochrysone.The formation of a leucohexaacetate suggests that the molecule contains two hydroxyl or potential hydroxyl oxygen functions in addition to the quinonoid and phenolic (or enolic) groups already shown to be present. The infrared spectra of mycochrysone and derivatives provide evidence that the remaining oxygen atom is ketonic. The principal chromophore of mycochrysone is related to 8-hydroxy-1,2-naphthoquinone. Hydrogenation experiments indicate that the pigment has a perylene carbon skeleton.

Synthesis of piperazine-2,5-diones related to bicyclomycin: 3-acetoxy-1,4-dibenzyl-3-[1-(2-methoxyethyl)- and 1-(2-hydroxyethyl)ethenyl]piperazine-2,5-dione. 1. Route via acyclic intermediates

1983 ◽  
Vol 61 (3) ◽  
pp. 519-528 ◽  
Author(s):  
Peter Yates ◽  
John Harold Hoare
Keyword(s):  
Sulfuric Acid ◽  
Carboxylic Acid ◽  
Oxygen Atom ◽  
Acetic Anhydride ◽  
Acid Chloride ◽  
Structural Features ◽  
Reaction Sequence ◽  
Hydroxyl Oxygen Atom ◽  
Compound 21 ◽  
Tetrahydropyranyl Ether

3-Acetoxy-1,4-dibenzyl-3-[1-(2-methoxyethyl)ethenyl]piperazine-2,5-dione (32) and its 2-hydroxyethyl analogue (46), which possess several of the structural features of the antibiotic bicyclomycin, have been synthesized by a route involving construction of the piperazine-2,5-dione ring at a late stage in the reaction sequence. Treatment of ethyl 3-(2-methoxyethyl)-3-methylglycidate with acetic anhydride and sulfuric acid gives ethyl 2-acetoxy-3-(2-methoxyethyl)-3-butenoate (10), which is converted to the corresponding carboxylic acid by ethanolysis, hydrolysis, and reacetylation. This, on conversion to its acid chloride and reaction with N,N′-dibenzylglycinamide, gives 2-acetoxy-N-benzyl-N-(2-benzylamino-2-oxocthyl)-3-(2methoxyethyl)-3-butenamide (21). Compound 21, on hydrolysis and oxidation, gives the corresponding 2-oxo compound, which on treatment with magnesium isopropylcyclohexylamide followed by acetylation yields 32. Demethylation of 21 with alkylthiotrimethylsilanes gives the corresponding 2-hydroxyethyl compound, whose tetrahydropyranyl ether on subjection to the above reaction sequence gives the 2-(tetrahydropyran-2-yloxy)ethyl analogue of 32. This, on hydrolysis, gives a 3: 1 mixture of compound 46 and a spiro compound formed by displacement of the acetoxyl group by the hydroxyl oxygen atom of 46.

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