Oxo isovalerate

Plants and microorganisms are capable of the de novo synthesis ofpantothenic acid from oxo-isovalerate and aspartate, by the pathway shown in Figure 12.3 animals are reliant on a preformed source of pantothenic acid. 

Oxo-isovalerate may be formed by the transamination of valine it is also the immediate precursor of valine biosynthesis and an intermediate in the synthesis of leucine (both are essential amino acids in mammals). Oxo-lso-valerate undergoes a hydroxymethyl transfer reaction, in which the donor is... 

Fig. 5.18 Mass spectra of the trimethylsilyl derivatives of the oximes of (a) 2-oxo-isovaleric acid and (b) 3-phenylpyruvic acid, (c) the methyloxime of 2-oxoglutaric acid, and the ethyloximes of (d) 2-oxoglutaric acid and (e) 3-phenylpyruvic acid.

Athamantin. 3-Methyibutanoic acid 8,9-dihydro-8-fl-m ethyl-I-(3-me thy i-I -oxobutoxy)ethylJ-2-oxo-2H-furo[2,3-h]-l. benzopyran-9-yl ester isovaleric acid diester with 8,9-dihydro-9-hydroxy-8-(l-hydroxy-l-methyUihyl)-... 

Biosynthesis Leu is formed from pyruvic acid - 2-acetolactic acid [acetolactate synthase (EC 4.1.3.18.)+(l-hydroxyethyl)-TPP] - 2,3-dihydroxy-isovaleric acid [reductase+NAD(P)H] - 2-oxoisova-leric acid [dihydroxyacid dehydratase] - 2-isopropyl-malate [2-isopropylmalate synthase + acetyl-CoA (EC 4.1.3.12)] -> 3-isopropylmalate [isopropylmalate dehydratase (EC 4.2.1.33) -HjO+HiO] 2-oxo-isocaproate [3-isopropylmalate dehydrogenase (EC 1.1.1.85) + NAD ] L. [leucine aminotransferase (EC... 

Allyl 3-methyl butyrate. See Allyl isovalerate 1-Allyl-3,4-methylenedioxybenzene 4-Allyl-1,2-methylenedioxybenzene. See Safrol (1S)-3-Allyl-2-methyl-4-oxocyclopent-2-enyl-(1 R)-trans-chrysanthemate. See,S-Bioallethrin 3-Allyl-2-methyl-4-oxo-2-cyclopenten-1-yl chrysanthemate dl-3-Allyl-2-methyl-4-... 

Fig. 10.1 Metabolites in the urine of an untreated patient with branched-chain keto aciduria (maple syrup urine disease). Extracted using ethyl acetate and separated as their trimethylsilyl-oxime derivatives on a 25 m SE-30 capillary column, using temperature programming from 80°C to 110°C at 0.5°C min and an injection split ratio 1 12 at a temperature of 250°C. The peaks marked R are due to solvent and reagents. Peak identifications are 1, lactic 2, 2-hydroxyisobutyric 3, 2-hydroxybutyric 4, pyruvic 5, 3-hydroxybutyric 6, 2-hydroxyisovaleric 7, 2-oxobutyric 8, 2-methyl-3-hydroxy-isovaleric 10, a and b, 2-oxoisovaleric 11, acetoacetic 12, 2-hydroxyisocaproic 13, 2-hydroxy-3-methyl- -valeric 14, 2-oxo-3-methyl-/i-valeric (14a L- 14b D-) 15, 2-oxoisocaproic acids. The internal standard was malonic acid. (Redrawn with modifications from Jellum etal., 1976)...

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