Nonenzymatic Transamination of Phenylglycine with 2-Oxoglutaric Acid Mediated by a Micellar Pyridoxal Model

Abstract

Phenylglycine undergoes transamination with 2-oxoglutaric acid in the presence of N-dodecylpyridoxal chloride (DPL) and hexadecyltrimethylammonium chloride (CTACl) under mild conditions. This is the first example of nonenzymatic overall transamination realized in the absence of metal ions.

Cysteine Conjugate β-Lyase-Dependent Biotransformation of the Cysteine S-Conjugates of the Sevoflurane Degradation Product 2-(Fluoromethoxy)-1,1,3,3,3-pentafluoro-1-propene (Compound A)

“…2-(Fluoromethoxy)-1,1,3,3,3-pentafluoro-1-propene (fluoroalkene 1) was provided by Abbott Laboratories (Abbott Park, IL). N-Dodecylpyridoxal bromide was synthesized by the method of Kondo et al (19). Trifluoroacetaldehyde ethyl hemiacetal, mercury(II) trifluoroacetate, 15-crown-5, and silica gel (Merck, grade 60, 240-400 mesh, 60 Å) were purchased from Aldrich Chemical Co. (Milwaukee, WI).…”

“…Melting points were determined with a Mel-Temp melting point apparatus and are uncorrected. 1 H and 19 F NMR spectra were recorded with a Bruker 270 MHz spectrometer operating at 270 MHz for 1 H and 254 MHz for 19 F. Chemical shifts, δ, are reported in parts per million (ppm). The internal standard (δ ) 0.0 ppm) for 1 H NMR with CDCl3 as the solvent was tetramethylsilane.…”

“…The objective of this work was to study the β-lyasedependent biotransformation of the fluoroalkene 1-derived cysteine S-conjugates S- [ pentafluoropropyl]-L-cysteine (4) and S-[2-(fluoromethoxy)-1,3,3,3-tetrafluoro-1-propenyl]-L-cysteine (5). The biotransformation of cysteine conjugate 4 by rat kidney cytosol or its chemical transformation by a pyridoxal model system was investigated by 19 F NMR spectroscopy and GC/MS. Incubation of conjugate 4 with rat kidney cytosol or a pyridoxal model showed the formation of fluoride, 2-(fluoromethoxy)-3,3,3-trifluoropropanoic acid (9), and 3,3,3-trifluorolactic acid (10).…”

“…Incubation of conjugate 4 with rat kidney cytosol or a pyridoxal model showed the formation of fluoride, 2-(fluoromethoxy)-3,3,3-trifluoropropanoic acid (9), and 3,3,3-trifluorolactic acid (10). Cysteine S-conjugate 5 was not stable in pH 7.4 buffer, and its degradation was followed by 19 F NMR and UV spectroscopy. Also, the synthesis of acid 9 and its characterization by 1 H and 19 F NMR spectroscopy and GC/MS are described.…”

“…Cysteine S-conjugate 5 was not stable in pH 7.4 buffer, and its degradation was followed by 19 F NMR and UV spectroscopy. Also, the synthesis of acid 9 and its characterization by 1 H and 19 F NMR spectroscopy and GC/MS are described. Finally, the stoichiometry of pyruvate, fluoride, and acid 9 formation from cysteine S-conjugate 4 was measured, and the formation of trifluorolactic acid 10 as a degradation product of acid 9 was demonstrated.…”