L-phosphinothricin

L-alanyl-L-2,3-epoxy-4-oxohexahydrophenylalanine [29393-20-2] C22H2gN20, inhibit glutamine metaboHsm, as does bialaphos as a source of the amino acid L-phosphinothricin [35597-44-5] 0 11 2 04 . 

Anionic trivalent phosphorus reagents have also been found to be of use in the preparation of some intriguing species. For example, an approach to L-phosphinothricin and related materials has been accomplished by addition of the conjugate base of alkyl methylphos-phonites to protected L-vinylglycine species (Equation 3.31).450 The starting protected L-vinylglycine species are readily available from l-methionine and L-glutamic acid. 

Zeiss, H.J., Enantioselective synthesis of L-phosphinothricin. III. Enantio-selective synthesis of L-phosphinothricin from L-methionine and L-glutamic acid via L-vinylglycine, Tetrahedron, 48, 8263, 1992. 

Applications of Transaminases towards Crop Protection Agents L-Phosphinothricin and (S)-MOIPA... 

Figure 7.31 Coupled process for the herbicide ingredient L-phosphinothricin with transaminases (Drauz, 2002).

Researchers have Isolated and characterized a transaminase from . coll K-12, specific for production of L-phosphInothrIcIn (I2g). Further work has resulted In cloning, characterization, and overexpression of the gene coding for the L-phosphlnothrlcIn-speclflc transaminase from . coll K-12. These results greatly facilitate biotechnological production of L-phosphInothrIcIn In an enzyme reactor. 

The active herbicidal agent L-phosphinothricin is obtained with enantiomeric excesses up to 91 % from the asymmetric hydrogenation of a-acylamidoacrylate precursors (eq 3). While yields of the primary hydrogenation products are quantitative, enantiomeric excesses increase slightly in reactions run in a H20/MeOH mixture. Adverse effects are observed in reactions carried out in THF/MeOH. 

Logusch, E.W., Facile synthesis of D,L-phosphinothricin from methyl 4-bromo-2-phthalimidobutyrate, Tetrahedron Lett., Tl, 5935, 1986. 

Other Preparative Applications of Aminotransferases 12.7.3.3.1 Preparative Applications L-Phosphinothricin... 

L-Phosphinothricin, the active ingredient of the broad-spectrum herbicide Basta (AgrEvo), can be obtained through enzymatic transamination of the corresponding oxoacid, 2-oxo-4-[(hydroxy)(methyl)phosphinoyl]butyric acid, in a coupled system with aspartate aminotransferase (AAT) and 4-aminobutyrate 2-ketoglutarate transaminase (E.C. 2.6.1.19) from E. coli (Fig. 12.7-6)[37 . In solutions containing 10% substrate, 85 % conversion was reached with only < 3 % amino acid by-products. For... 

L-phenylalanine was prepared from L-tyrosine by chemical methods, in an overall yield of 75%. A series of peptides containing a-aza-amino acid residues has been prepared 7 one member of the series, N[(1-carboxyethyl)carbamoyl]-valylglyclyl-a-aza-alanine benzyl ester, is substantially more potent than several azapeptide inhibitors of elastase hitherto reported. D,L-Phosphinothricin (49), D,L-2-amino-4-phosphonobutyric acid (50), and aminocyclopropanecarboxylic acid have all been prepared from methyl-4-bromo-2-phthalimidobutyrate using simple procedures (Scheme 83).177... 

In 1968 Ronzio and Meister had already developed a model for GS inhibition by methionine sulfoximine (MSO) [21]. They postulated that MSO inhibits GS in two steps. The first step is reversible when the inhibitor competes with glutamate at the binding site. In the second step the substrate analogue is phosphorylated (Scheme 6.3.2) and then irreversibly bound to the enzyme. Manderscheid and Wild [22] confirmed the two-step hypothesis using L-phosphinothricin in their inhibition studies with GS from wheat. They found that the phosphorylated phosphinothricin was irreversibly bound to the enzyme. Furthermore, they concluded that each subunit of the enzyme is able to bind one molecule of phosphinothricin. 

Di-phosphinothridn 307 L-phosphinothricin 303, 307 phosphinothricyl alanyl-leucine 307 2-phosphoglycolate 303 phoxim 760 phthalide 973 Pico 206, 1222... 

Leaf and root explants from axenically grown seedlings of L fendleri regenerate shoots profusely on MS medium with 3% sucrose and 1 mg/L each of benzyl adenine and zeatin. These explants were cocultivated Agrobacterium tumefaciens harbouring a binary transformation vector whose T-DNA carries genes conferring resistance to either the herbicide L-phosphinothricin (L-PPT) or to kanamycin. 

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