Benzoylformate

Mocimycin has been chemically converted to aurodox by protection of the 4-hydroxy group at the pyridone moiety as the benzoylformate, followed by /V-methylation and hydrolytic removal of the protective group (1,55). Whereas aurodox esters are active growth promotors in animals, goldinamines that are A/-acylated by acids other than goldinonic acid, such as acetic, benzoic, or arylsulfonic acids, lack useful antimicrobial or growth-promoting activity (1). 

The benzoylformate ester can be prepared from the 3 -hydroxy group in a deoxy-ribonucleotide by reaction with benzoyl chloroformate (anh. Pyr, 20°, 12 h, 86% yield) it is cleaved by aqueous pyridine (20°, 12 h, 31% yield), conditions that do not cleave an acetate ester. ... 

The benzoylformate ester can be prepared from the 3 -hydroxy group in a deoxyribonucleotide by reaction with benzoyl chloroformate (anhyd. Pyr, 20°,... 

V760 mm., is collected. The yield of ethyl benzoylformate is 155-175 g. (35-40 per cent of the theoretical amount). (Note 10). 

It is advisable not to stop the experiment until after filtration since manganese dioxide slowly oxidizes benzoylformic acid to benzoic acid. 

The benzene contains 80 g. of impure ethyl benzoate boiling at 180-260° and containing about 20 per cent of ethyl benzoylformate. In the case of the methyl ester the benzene contains 60 g. of impure methyl benzoate, boiling at 170-250°, and containing about 20 per cent of methyl benzoylformate. 

This sodium carbonate solution contains about 4 g. of impure benzoylformic acid. 

Ethyl benzoylformate has been prepared by the direct esterification of the acid 1 and by the action of oxides of nitrogen on an alcoholic suspension of indigo.2 The acid has been prepared by many different reactions but the most practical are the hydrolysis of benzoyl cyanide,3 the oxidation of acetophenone 4 and the oxidation of mandelic acid.5... 

Tsou AY, SC Ransom, JA Gerlt, DD Buechter, PC Babbitt, GL Kenyon (1990) Mandelate pathway of Pseudomonas putida sequence relationships involving mandelate racemase, (5)-mandelate dehydrogenase, and benzoylformate decarboxylase and expression of benzoylformate decarboxylase in Escherichia coli. Biochemistry 29 9856-9862. 

The mandelate pathway in Pseudomonas putida involves successive oxidation to benzoyl formate and benzoate, which is further metabolized via catechol and the 3-ketoadipate pathway (Figure 8.35a) (Hegeman 1966). Both enantiomers of mandelate were degraded through the activity of a mandelate racemase (Hegeman 1966), and the racemase (mdlA) is encoded in an operon that includes the next two enzymes in the pathway—5-mandel-ate dehydrogenase (mdlB) and benzoylformate decarboxylase (mdlC) (Tsou et al. 1990). 

Benzoylformic acid can be prepared by the oxidation of acetophenone with potassium permanganate in alkaline solution,1 by the oxidation of mandelic acid with potassium perman-... 

Table 41.14 Rhodi um-catalyzed hydrogenation of acetophenone (A) and ethyl benzoylformate (B) [105].

Actually the reaction of the dimer [Fe(bd bpza)Cl]2 (5) with thallium benzoylformate results in the purple benzoylformato complex [Fe(bd bpza)(02CC(0)Ph)] (6). The purple color is caused by a visible absorption at 544 nm (Fig. 8). 

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