Results 131 to 140 of about 669 (167)

On the Decomposition of 1,2,4-Trioxan-5-ones

HETEROCYCLES, 1993
The thermal and chemical properties of six 3,6-substituted 1,2,4-trioxan-5-ones were studied by flash-vacuum thermolysis (FVT) and by treatment with electron-transfer agents. The 1,2,4-trioxan-5- ones exhibited unusual stability both chemically and thermally, but eventually underwent decomposition with loss of carbon dioxide yielding the carbonyl ...
Jefford, Charles, Vicente, Maria Da Graca Henriques   +1 more
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Geraniol-derived 1,2,4-Trioxanes with potent in-vivo antimalarial activity

Bioorganic & Medicinal Chemistry Letters, 2003
Geraniol, an abundantly available naturally occurring allylic alcohol, has been used as a starting material to prepare a series of 6-[alpha-(3'-aryl-3'-hydroxypropyl)vinyl]-1,2,4-trioxanes. Some of these novel trioxanes have shown very promising antimalarial activity against multi-drug resistant Plasmodium yoelii in mice by both intramuscular (im) and ...
Chandan, Singh, Nitin, Gupta, Sunil K, Puri   +2 more
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Antimalarial Peroxide Dyads from Natural Artemisinin and Hydroxyalkylated 1,2,4-Trioxanes

Journal of Medicinal Chemistry, 2009
Three synthetic approaches to highly antimalarial peroxide dyads that are composed of the natural artemisinin part (either as dihydroartemisinin or artesunic acid components) and synthetic 1,2,4-trioxanes linked by ether or ester bridges are described.
Axel G, Griesbeck, Jörg, Neudörfl, Achim, Hörauf, Sabine, Specht, Angela, Raabe   +4 more
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ChemInform Abstract: A Halogenocyclization Route to 1,2,4‐Trioxanes.

ChemInform, 1994
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
A. J. BLOODWORTH, A. SHAH
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An Unusual Acid-catalyzed Rearrangement of 1,2,4-Trioxanes

HETEROCYCLES, 1993
A new Lewis acid-catalyzed rearrangement of the peroxide group in two 1,2,4-trioxanes, deoxoartemisinin and 12β-allyldeoxoartemisinin, yielding ring enlarged oxide, is ...
Herman Ziffer, Yu-MIng Pu, Herman Yeh
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Synthesis of in vivo potent antimalarial 1,2,4-trioxanes

Bioorganic & Medicinal Chemistry Letters, 1992
Abstract β-Hydroxyhydroperoxides ( 5a–h ) derived from 3-aryl-2-butenol ( 6a–h ) by dye-sensitized photooxygenation undergo a facile acid-catalysed condensation with 2-adamantanone to yield 1,2,4-trioxanes ( 8a–h ). These trioxanes are stable at room temperature, can be stored in refrigerator for a year and are active against ...
Chandan Singh, Dharmendra Misra, Gunjan Saxena, Subhash Chandra   +3 more
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Chemistry of 1,2,4-Trioxanes: Metal-Induced Deoxygenation and Rearrangement of the 1,2,4-Trioxane Obtained by Photooxidation of β-Ionone

Synthesis, 2002
The reactivity of 2,2,6,8-tetramethyltricyclo(6.2.2.0 1 . 6 )dodecene (2) toward different metal salts has been explored. In the presence of Fe(II), Sn(II) and Ce(IV) ions compound 2 underwent a rearrangement process to afford acyclic triketones Z-3 and E-3. The action of Zn powder in acetic acid resulted in an unexpected formation of furan 4 in high
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A DFT study of Artemisinin and 1,2,4-trioxane

Journal of Molecular Structure: THEOCHEM, 1999
Abstract The powerful anti-malarial drug, Artemisinin (Qinghaosu), and the model molecule 1,2,4-trioxane in both chair and boat/twisted form have been studied by the quantum chemistry calculation method at the ab initio SCF HF and the DFT level with 6-31G* basis sets. On comparing the optimized geometry of 1,2,4-trioxane with Artemisinin, it has been
Jiande Gu, Kaixian Chen, Hualiang Jiang, Ruyun Ji   +3 more
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A New Approach to 1,2,4‐Trioxanes form Cyclic Allylic Hydroperoxides

Helvetica Chimica Acta, 1984
AbstractSummary The reaction of 4,5‐dimethyl‐4‐hydroperoxy‐1(4H)‐nephthalenone (9) with acetaldehyde, pivalaldehyde, benzaldehyde, and p‐chlorobenzaldehyde in CH2Cl2 in the presence of Amberlyst‐15 as catalyst gave the corresponding cis‐3‐methyl, t ‐butyl, phenyl and p ‐chlorophenyl derivatives of 10,10b‐dimethylnaphtono[2,1‐e][1,2,4]trioxin‐6(5)H‐one ...
Jefford, Charles, Jaggi, Danielle, Kohmoto, Shigeo, Boukouvalas, John, Bernardinelli, Gérald Hugues   +4 more
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New, Antimalarial, Tricyclic 1,2,4-Trioxanes: Evaluations in Mice and Monkeys

The American Journal of Tropical Medicine and Hygiene, 1994
We have concluded initial preclinical studies with synthetic trioxanes numbered 3-9 and have compared them with artemisinin (numbered 1) using CD-1 mice infected with Plasmodium berghei. Based on their antimalarial effectiveness in mice, two of these synthetic trioxanes were selected for evaluation in Aotus monkeys infected with multidrug-resistant ...
G H, Posner, C H, Oh, H K, Webster, A L, Ager, R N, Rossan   +4 more
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