Synthesis gram-scale

With L-glyceraldehyde as substrate, the same extract catalyzed a half-gram scale synthesis of 1 -deoxy-L-f/ueo-pentulose. 

This thermodynamic driving force is particularly useful tvith multienzyme equilibrium systems such as that used in the gram-scale synthesis of tv ro equivalents ofo-xylulose 5-phosphate (104) from (26) (Figure 10.38) [171,172]. Similarly, the corresponding 1-deoxy-D-xylulose 5-phosphate tvas efficiently produced from pyruvate and (34) by the catalytic action of the thiamine diphosphate-dependent 1-deoxy-D-xylulose 5-phosphate synthase (DXS) (EC 2.2.1.7) from E. coli [173]. 

Electric-field-directed growth of gold nanorods in aqueous surfactant solutions. Advanced Functional Materials, 14, 571-579 (d) Jana, N.R. (2005) Gram-scale synthesis of soluble, near-monodisperse gold nanorods and other anisotropic nanoparticles. Small,... 

Smith, A.B. Ill, Beauchamp, T.J., LaMarche, M.J. etal. (2000) Evolution ofa Gram-Scale Synthesis of (-F)-Discodermolide. Journal of the American Chemical Society, 122, 8654-8664. 

G. Ning, Z. Fan, G. Wang, J. Gao, W. Qian, F. Wei, Gram-scale synthesis of nanomesh graphene with high surface area and its application in supercapacitor electrodes, Chemical Communications, 47 (2011) 5976. 

A practical, inexpensive one-step procedure was developed for the RhaD-catalyzed gram-scale synthesis of L-fructose. The requirement for DHAP as the donor substrate was circumvented by use of borate buffer, presumably by in situ formation of borate esters as a phosphate ester mimic. Racemic glyceraldehyde was also used, as the enzyme preferentially accepted the L-enantiomer as a substrate. The method can also be apphed to other products, including L-rhamnulose, and towards a two-step synthesis of L-iminocychtols. ... 

Xylulose 5-phosphate (D-threo-2-pentulose 5-phosphate) is the best donor compound for TKT [6]. As its cost is, however, prohibitively high for routine assays (formerly available batches from commercial suppliers were sold at ca. 1000 per 100 mg), a multi-enzymatic synthesis and subsequent chromatographic purification were developed which allowed the gram-scale synthesis of xylulose 5-phos-phate with a 82% yield [13]. 

Irurre, J. Riera, M. Guixa, M. Gram-scale synthesis of (+)- and (-)-trans-10-amino-9-hydroxy-9,10-dihydrophenanthrene by enzymic hydrolysis. Chirality 2002, 14 490-494. 

Smith and co-workers reported their second-generation approach to discodermolide in 1999, which was now performed in the correct enantiomeric series [46—48]. By carefully redesigning the route, the overall number of steps was significantly reduced and, importantly, it enabled a gram-scale synthesis. As outlined in Scheme 7, the key bond constructions at C8-C9 and C14-05 were retained, while strategic modifications involved the earlier introduction of the terminal (Z)-diene unit in 44 and a revised C1-C8 subunit 45. 

Very recently, the fusion protein and a recombinant human a2,6-sialyltransferase (hST6Gal-I) have been used in gram-scale synthesis of sialosides (65). 

Samain E, Drouillard S, Heyraud A, Driguez H, Geremia RA Gram-scale synthesis of recombinant chitooUgosaccharides in Escherichia coli. Carbohydr. Res. 1997 302 35-42. 

Certain aromatic analogues of natural amino acids can be used as potential fluorescent probes of peptide structure and dynamics in complex environments. The research team of M.L. McLaughlin undertook the gram scale synthesis of racemic 1- and 2-naphthol analogues of tyrosine. The synthesis of the 1-naphthol tyrosine analogue started with the Gattermann formylation of 1-naphthol using the Adams modification to afford the formylated product 4-hydroxy-1-naphthaldehyde in 67% yield. 

Kammermeier and Jendralla have employed NbCl3 in a gram-scale synthesis of a C2-symmetric HIV-protease inhibitor (Eq. 3.20) [38]. Homocoupling of the illustrated dipeptide proceeds in modest yield and with good (>9 1 synp.synf) diastereoselectivity. 

J. E. Heidlas, W. J. Lees, P. Pale, and G. M. Whitesides, Gram-scale synthesis of uridine 5 -diphospho-A-acetylglucosamine. Comparison of enzymatic and chemical routes, J. Org. Chem., 146 (1992) 146-151. 

Scheme 5.9 Efficient synthesis of imidazo[1,2-a]pyridines (a) general reaction conditions and (b) gram-scale synthesis of zolimidine.

The most practical gram scale synthesis of the acid 2 and related monomethylated derivatives was reported by Benigni and Minnis (65JHC387) (Scheme 12) and involves condensation of 4,5-dibenzyloxy-2-nitrotoluene with diethyl oxalate promoted by potassium ethoxide. Reductive cyclization of the resulting 2-nitro-4,5-dibenzyloxyphenylpyruvic acid with Fe powder in ethanol/acetic acid then leads... 

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