Enzymatic synthesis allysine ethylene acetal

Enzymatic Synthesis of At lysine Ethylene Acetal. (S)-2-Amino-5-(l,3-dioxolan-2-yl)-pentanoic acid (5 )-allysine ethylene acetal (7) (Fig. 3A) is one of three building blocks used in an alternative synthesis of Omapatrilat (1). It previously had been prepared via an eight-step chemical synthesis from 3,4-dihydro [2H] pyran (16). An alternate synthesis of (7) was demonstrated by reductive amination of ketoacid acetal (8) using phenylalanine dehydrogenase (PDH) from Thermoactinomyces intermedins (17). The reaction required ammonia and NADH NAD produced during the reaction was recycled to NADH by the oxidation of formate to CO using formate dehydrogenase (FDH). 

Fig. 3. (A) Enzymatic synthesis of chiral synthon for Omapatrilat (1) Reductive amination of keto acid acetal (8) to (S)-allysine ethylene acetal (Z) by phenylalanine dehydrogenase. Regeneration of NADH was carried out using formate dehydrogenase. (B) Enzymatic synthesis of chiral synthon for Omapatrilat (1) Conversion of disulfide (U) to thiazepine (9) by S-lysine a-aminotransferase.

Vanlev enzymatic synthesis of allysine ethylene acetal. 

VANLEV ENZYMATIC SYNTHESIS OF ALLYSINE ETHYLENE ACETAL... 

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