Enzymatic synthesis propionic acid

The tetramerization of suitable monopyrroles is one of the simplest and most effective approaches to prepare porphyrins (see Section 1.1.1.1.). This approach, which is best carried out with a-(hydroxymethyl)- or ot-(aminomethyl)pyrroles, can be designated as a biomimetic synthesis because nature also uses the x-(aminomethyl)pyrrole porphobilinogen to produce uroporphyrinogen III. the key intermediate in the biosynthesis of all kinds of naturally occurring porphyrins, hydroporphyrins and corrins. The only restriction of this tetramerization method is the fact that tnonopyrroles with different -substituents form a mixture of four constitutionally isomeric porphyrins named as porphyrins I, II, III, and IV. In the porphyrin biosynthesis starting from porphobilinogen, which has an acetic acid and a propionic acid side chain in the y6-positions, this tetramerization is enzymatically controlled so that only the type III constitutional isomer is formed. 

While many methods have been reported for the synthesis of chiral 2-hydroxy acids, few have proven to be reliable toward the synthesis of the title compound in terms of overall yield and enantioselectivity. Herein we describe a continuous enzymatic process for an efficient synthesis of (R)-3-(4-fTuorophenyl)-2-hydroxy propionic acid at a multi-kilogram scale with a high space-time yield (560 g/L/d) using a membrane reactor. The product was generated in excellent enantiomeric excess (ee>99.9%) and good overall yield (68-72%). This process can also be adapted to the synthesis of a variety of chiral 2-hydroxy acids with high yield and stereoselectivity. 

Protease inhibitor enzymatic synthesis of (/ )-3-(4-fiuorophe-nyi)-2-hydroxy propionic acid. 

Antidiabetic drug (GLP-1 mimics) enzymatic synthesis of (S)-amino-3-[3- 6-(2-methylphenyl) pyridylj-propionic acid. 

Imidazolone propionate hydrolase catalyzes the enzymatic cleavage of the imidazole ring to yield formi-minoglutamate. The rat liver enzyme has been partially purified. In addition to the enzymic conversion, two nonenzymic spontaneous reactions yield N-formyl-isoglutamine and 4-oxoglutamic acid. In addition to the oxidative pathways for histidine, there exist three other pathways for its use protein synthesis, decarboxylation to yield histamine (see Inflammation), and transaminase. The activity of histidine pyruvic transamination in rat liver is three times that of histidase. The product of the transaminase reaction is imidazole pyruvic acid, which in turn is converted to imidazole acetic acid. 

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