An Improved Synthesis of Homocitrate
نویسندگان
چکیده
Monoethyl malonate (1) and tert-butyl alcohol are esterified by catalysis with dicyclohexylcarbodiimide and 4-dimethylaminopyridine to yield ethyl t-butyl malonate (2). The ethoxymagnesio derivative (3) of the ester is condensed with β-carbomethoxypropionyl chloride to give the triester (4), which is decomposed by heating under vacuum in the presence of β-naphthalensulfonic acid to give ethyl methyl β-ketoadipate (5). Compound 5 is reacted with hydrogen cyanide,followed by hydrolysis of the cyanohydrin to give the free acid (6). Compound 6 is converted to homocitrate (7) by the use of an improved procedure.
منابع مشابه
Inhibition and repression of homocitrate synthase by lysine in Penicillium chrysogenum.
Homocitrate synthase in the first enzyme of the lysine biosynthetic pathway. It is feedback regulated by L-lysine. Lysine decreases the biosynthesis of penicillin (determined by the incorporation of [14C]valine into penicillin) by inhibiting and repressing homocitrate synthase, thereby depriving the cell of alpha-aminoadipic acid, a precursor of penicillin. Lysine feedback inhibited in vivo the...
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We previously reported that lysine inhibits in vivo homocitrate synthesis in the lysine bradytroph, Penicillium chrysogenum L(1), and that such feedback inhibition could explain the known lysine inhibition of penicillin formation. In the present study, it was found that dialyzed cell-free extracts of mutant L(1) converted [1-(14)C]acetate to homocitrate. This homocitrate synthase activity was e...
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