Amides, oxidative cleavage

DJERASSI RYLANDER Oxidation Ru04 in oxidative cleavage ot phenols or alkenes oxidation ol aromatics to quinones oxidation ol alkyl amides to irmdes or ol ethers lo esters... 

It was postulated (169) that these amides are 8,8a-secobenzophenanthridine alkaloids produced by oxidative cleavage of ring B of the corresponding benzophenanthridines. The success of Baeyer-Villiger-type oxidations of the immonium bond of benzophenanthridine skeletons (168,171,172,175) indicates that this type of oxidation could be a real biological pathway. 

Soai and co-workers reported the oxidative cleavage of the pyrimidine ring in pyrimidines 106 to produce chiral acetamides 107 along with amides 108 with excellent retention of optical purity <00H151>, This is claimed to be the first such oxidative cleavage of the pyrimidine ring. 

Peng HM, Raner GM, Vaz AD, et al. Oxidative cleavage of esters and amides to carbonyl products by cytochrome P450. Arch Biochem Biophys 1995 318(2) 333—339. 

This electrochemical oxidation mediated by NHPI was applicable to benzylic carbons, allylic carbons, deprotection of acetals, oxidative cleavage of cyclic acetals and amide to afford benzoylated compounds, enones ", carbonyl compounds, -hydroxyethyl esters and imides, respectively (equations 31-35). 

Oxidative cleavage of amines 9-39 Reduction of amides 9-47 Reduction of nitro compounds 9-50 Reduction of nitroso compounds or hydroxylamincs 9-51 Reduction of oximes 9-52 Reduction of azides 9-53 Reduction of isocyanates, isothiocyanates, or N-nitroso compounds 9-55 Reduction of amine oxides 9-59 Reduction of azo, azoxy, or hydrazo compounds... 

Bestatin 6a (Figure 3.6.8) is the lead structure of a family of highly potent protease inhibitors containing the 3-amino-2-hydroxy-4-phenylbutanoic acid as the active, isosteric motif, mimicking the tetrahedral intermediate formed during amide bond cleavage [31]. Several clinically employed HIV-protease inhibitors are from this class of compound. The oxidized a-keto-/ -amino derivatives have also... 

Cu(II)-Cu(I) Oxidative Catalysis Oxidative Cleavage Reactions and Cyclizations of Amides... 

An interesting application to the synthesis of a-diketones, a-ketoesters and a-ketoa-mides, starting from ketones, esters and amides, was achieved by Wasserman and Ives . The method involves conversion of the starting carbonyl compound to the corresponding enamino carbonyl compound, followed by oxidative cleavage of the enamine double bond by singlet oxygen (Scheme 7). 

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