15 2,5-Dihydroxymethyl-3,4-dihydroxypyrrolidine

The most significant indication that the biocatalytic properties also depend on the expression host comes from our studies on the fructose analogues DMDP 10 (2,5-dihydroxymethyl-(3S,4R)-dihydroxypyrrolidine) and 5-deoxy-D-fructose as inhibitors of SuSyl (Fig. 2.2.6.2). In contrast to SuSyl from yeast, the strongest inhibitor for recombinant SuSyl from E. coli is 10 (IC501.5 mM), suggesting that the enzyme prefers the D-fructofuranose conformation. 

Synthesis from o-fructose D-Fructose has been used for the synthesis of 2R,5S-dihydroxymethyl-31 ,47 -dihydroxypyrrolidine (3) and its analogues (Scheme 4). Thus, microbial oxidation of D-fructose led to 5-keto-D-fructose (24), which was condensed with Ph2CHNH2 to afford a mixture of 25, 26 and 27 in a ratio of 86 8 6. Removal of the benz-hydryl group from 25 by hydrogenation in the presence of Pd(OH)2 afforded 3 in 91 % yield. 

Various pyrrolidines were prepared by using the chemoenzymatic approach. Thus, 2R,5S-dihydroxymethyl-3R,4A -dihydroxypyrrolidine (3) was prepared from the L-sorbose derivative 36 (Scheme 6). Thus, periodate oxidation of 2-azido-2-deoxythreitol (34) led to 2-azido-3-hydroxypropanal (35), which was treated with DHAP and FDP aldolase to... 

CsHi3NOu, 2,5-Dihydroxymethyl-3,4-dihydroxypyrrolidine, 43B, 264 C6H13N3O, 1,4-Dimethyl-5-ethyl-5-hydroxy-62-1,2,3-triazoline, 39B, 156... 

R,5R-Dihydroxymethyl-3/ ,4R-dihydroxypyrrolidine (2,5-dideoxy-2,5-imino-D-mannitol, DMDP) has been isolated from the fermentation broth of Strepto-myces sp. KSC-5791 along with minor amounts of deoxynojirimycin and deoxymannojirimycin. The DMDP was shown to be a potent inhibitor of trehalases from Corynebacterium sp. and the diamondback moth (Phytella... 

Class 1 are the pyrrolidine alkaloids having five-membered ring structures, as shown by DMDP, i.e. 2,5-dihydroxymethyl-3,4-dihydroxypyrrolidine [5] (Figure lA). 

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