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Cephalosporin sulfoxides

This chapter covers only the chiral compounds that are cited in the literature by virtue of their optical activity. To keep the chapter to an acceptable length, a discussion of the stereochemical properties of sulfenamides showing axial chirality is omitted (17). Similarly, to limit the scope of the review, the chemistry of penicillin, cephalosporin sulfoxides and related compounds (14,18,19), steroidal sulfoxides (15,16), and other naturally occurring chiral sulfur compounds (4) is not discussed. For the same reason, only selected results are discussed and in some cases only references are given to recent papers and review articles on special topics. [Pg.335]

E. T and Hosztafi, S The Mannich reaction of cephalosporin sulfoxides and sulfones, Acta Chim. Acad ScL Hung., 110. 81, 1982 Chem. Abstr.. 98, 16465, 1983. [Pg.81]

Penicillin and cephalosporin sulfoxides. A number of reagents have been used to prepare these sulfoxides. Actually hydrogen peroxide (327o), one of the cheapest reagents, in CH2CI2 in combination with excess formic acid (or acetic acid) appears to be the best reagent. Yields of 85-100% of sulfoxides are obtainable in this way. Excess acid minimizes sulfone formation and decreases the reaction time. ... [Pg.129]

Deoxygenation. Penicillin and cephalosporin sulfoxides, (1) and (3), are deoxygenated in high yield by PaSs (0.5 mole equiv.) and pyridine at 20° (16 hours). ... [Pg.149]

NMR has proved invaluable in elucidating the two dimensional structure, as well as the conformation and configuration of penicillins, cephalosporins, and their derivatives. Penicillin and cephalosporin sulfoxides have been a favorite subject of NMR studies (Bose et ai, 1972 Vlietinck et al., 1974 Lammert and Kukolja, 1975 Dobson et al., 1975 Busson et al., 1976 Harrison and Hodge, 1976). The stereochemical assignments of the sulfoxide functionality R (39) or 5 (40) have been made in accordance with the procedure described by Demarco and Nagarajan (1973). [Pg.526]

A high-yielding method for deoxygenation of sulfoxides to sulfides involves treatment with 1.1 equiv tin(II) chloride in the presence of a catalytic amount (0.4 equiv) of AcCl (MeCN/DME, 0 °C rt). The mildness of this method is demonstrated by its usability for deoxygenation of a cephalosporin sulfoxide (eq 16). [Pg.13]

Sila-Morin-Rearrangement of Penicillin Sulfoxides to Cephalosporins... [Pg.200]

Rearrangements involving sulfoxides have played an important role in the development of the chemistry of sulfoxides. It is therefore not surprising that all major literature surveys on sulfoxides " , or their sulfenate precursors , also include a discussion of this subject. However, while excellent and detailed coverage exists for certain rearrangements of general mechanistic and synthetic interest, such as, for example, the Pummerer " or the related penicillin sulfoxide-cephalosporin " rearrangement, the treatment of all... [Pg.717]


See other pages where Cephalosporin sulfoxides is mentioned: [Pg.291]    [Pg.291]    [Pg.291]    [Pg.122]    [Pg.291]    [Pg.101]    [Pg.582]    [Pg.498]    [Pg.291]    [Pg.291]    [Pg.291]    [Pg.122]    [Pg.291]    [Pg.101]    [Pg.582]    [Pg.498]    [Pg.315]    [Pg.31]    [Pg.32]    [Pg.32]    [Pg.33]    [Pg.286]    [Pg.289]    [Pg.291]    [Pg.293]    [Pg.305]    [Pg.307]    [Pg.738]    [Pg.824]    [Pg.718]    [Pg.824]    [Pg.30]    [Pg.93]    [Pg.551]    [Pg.563]    [Pg.566]    [Pg.286]    [Pg.289]    [Pg.291]    [Pg.293]    [Pg.305]    [Pg.307]    [Pg.286]    [Pg.289]   
See also in sourсe #XX -- [ Pg.248 ]

See also in sourсe #XX -- [ Pg.290 ]




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