2- Oxo-3-methylvalerate

Peroxisomes from rnunq-bean (vignu radiata i..) hypocotyls activate, by oxidative decarboxylation, 2-oxoisocaproate, 2-oxoisovalerate and 2-oxo-3-methylvalerate which are derived by transamination from leucine. 

The commonly used derivatives for oxo acids, the TMS-oxime, form single peaks for most acids as shown in Fig. 4.3 (Stemowsky et al., 1973) with the exception of 2-oxo-3-methylvaleric which gives a doublet arising from the D and L forms. Fortunately the D-form is not naturally occurring in physiological fluids. The retention times of the TMS-oxime-TMS-ester derivatives are... 

Fig. 4.3 Chromatogram of standard oxo acids separated as their trimethysilyl-oxime derivatives on 3 per cent OV-17 using temperature programming from 110°C to 220°C. Peak identifications are 1, pyruvate 2, 2-oxobutyrate 3, 2-oxoisovalerate 4, 2-0X0valerate 5, L-2-oxo-3-methylvalerate 6, 2-oxoisocaproate plus 7, d-2-oxo-3-methylvalerate 8, 2-oxo-4-methylthiobutyrate 9, 2-oxoglutarate 10, phenylpyruvate. (Redrawn with modifications from Sternowsky etal., 1973)...

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