Streptomyces amakusaensis

Combining, in tandem, the nitro-aldol reaction with the Michael addition using thiophenol is a good method for the preparation of P-nitro sulfides as shown in Eqs. 4.2 and 4.3. This reaction is applied to a total synthesis of tuberine. Tuberine is a simple enamide isolated from Streptomyces amakusaensis and has some structural resemblance to erbastatin, an enamide which has received much attention in recent years as an inhibitor of tyrosine-specific kinases. The reaction of p-anisaldehyde and nitromethane in the presence of thiophenol yields the requisite P-nitro sulfide, which is converted into tuberine via reduction, formylation, oxidation, and thermal elimination of... 

A ThrA enzyme that is highly specific for L-threo stereoisomers has been detected in Streptomyces amakusaensis. The purified enzyme has been employed for the efficient resolution of chemically generated racemic f/ireo-phenylserines 156, substituted at the p-position (H, OH, Br, N02), to furnish enantiomerically pure D-amino acids 157 as the (2R,3S) diastereomers [459], Preliminary screening results suggest a broad substrate tolerance [460]. 

C,oH,NC>2,Mr 177.20, prisms, mp. 132-133 °C, antibiotic from Streptomyces amakusaensis. active against mycobacteria. 

Aryl analogs of threonine 94 (Fig. 32) are of interest for their occurrence as constituents of a number of antibiotics (e.g., vancomycin). Because of often unfavorable equilibrium constants [43], synthetic reactions usually lead to stereoisomer mixtures due to thermodynamic control [152,153]. Resolution of diastereomeric material (93/94) by retroaldolization under kinetic control is more successful, as has been demonstrated by the preparation of enantiopure p-substituted (2i ,35)-phenylserines 94 [154] and (2R,3R)-3-hetarylserines [155] using a threonine aldolase from Streptomyces amakusaensis that is selective for aromatic threo substrates. 

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