- METAL-ASSISTED REACTIONS-13. RAPID, SELECTIVE REDUCTIVE CLEAVAGE OF PHENOLIC HYDROXYL GROUPS BY CATALYTIC TRANSFER METHODS
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Previous work has shown that, after converting phenols into suitable phenolic ethers, the aromatic C-O bond of the original phenol can be reductively cleaved heterogeneously to give a C-H bond through the use of molecular hydrogen or hydrogen donors together with a transition metal catalyst.The present work provides a method for selectively replacing a phenolic OH group by H in just a few minutes, compared with the 2 to 4 hr required previously using a hydrogen donor and the several hours under pressure required for molecular hydrogen.Various kinds of groups are suitable for preparing the required phenolic ethers from phenols, but the best ones are strongly electronwithdrawing heteroaromatic entities.Solvent appears to play an important role in this heterogeneous reaction, the mechanism of which is discussed.
- Hussey, Brendan J.,Johnstone, A. W.,Entwistle, Ian D.
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p. 3775 - 3781
(2007/10/02)
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- Synthesis and anti-inflammatory evaluation of 3-methylthio-1,2,4-triazines, 3-alkoxy-1,2,4-triazines, and 3-aryloxy-1,2,4-triazines
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To develop nonacidic, nonsteroidal anti-inflammatory agents without GI complications, a series of asymmetric triazines was synthesized and evaluated for anti-inflammatory efficacy in the carrageenan-induced pedal edema assay. Toxicity was estimated by determination of approximate LD50 values in mice. 25 Compounds possessed activity comparable to the standard, indomethacin. Thirteen of the 25 compounds were selected for dose-response evaluation in the carrageenan assay based on their relative toxicity and anti-inflammatory activity. Neurotoxicity of the 13 triazines was estimated by determination of NTD50 values in mice. Five of the 13 compounds tested in the dose-response assay were active in terms of anti-inflammatory efficacy (ED50 values) and lack of overt neurotoxicity (NTD50 values) when compared to indomethacin. To determine the effect of these five developmental triazines on chronic inflammation, they were evaluated in the adjuvant-induced polyarthritis assay. One was comparable to indomethacin in reducing adjuvant-induced inflammation in this assay.
- Heilman,Heilman,Scozzie,Wayner,Gullo,Ariyan
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p. 282 - 287
(2007/10/02)
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- Pharmacologically active substituted 1,2,4-triazines
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Substituted 1,2,4-triazines, compositions thereof and methods of using same are described. The compounds of the invention exhibit a wide range of pharmacological activity including anti-inflammatory, analgesic, anti-pyretic, hypotensive and central nervous system effects.
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