Epimerization of amoxicillin piperazine-2,5-dione in acidic solutions.
نویسندگان
چکیده
منابع مشابه
1,4-Bis(3-methylphenyl)piperazine-2,5-dione
The asymmetric unit of the title compound, C(18)H(18)N(2)O(2), consists of two independent mol-ecules, each of which is located about a center of inversion. The mol-ecules are not planar, showing dihedral angles of 55.84 (9) and 54.10 (8)° between the piperazinedione and the aromatic rings. The piperazine N atoms exhibit a planar configuration. The crystal packing is stabilized by inter-molecul...
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The structure-activity relationships within a series of penicillins and cephalosporins containing an N(4)-substituted piperazine-2,3-dione moiety in the C(6)/C(7)-beta-side chain are discussed.
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The electrochemical reduction of H2O2 on SIMFUEL was investigated over the pH range 1 to 4. The mechanism at pH 4 is known to occur on U species incorporated into a surface layer of U1-2xU2xO2+x. However, below pH 3, reduction occurs on an adsorbed UO2(OH) state which is unstable and oxidizes to insulating U before dissolving as UO2. Both schemes are observed at intermediate pH’s. The presence ...
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ژورنال
عنوان ژورنال: Chemical and Pharmaceutical Bulletin
سال: 1986
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.34.2239