Deoxynojirimycin, isolation

Several trehalase inhibitors have been isolated from natural sources these include deoxynojirimycin, validamycins, validoxylamines, salbastatin, calystigin B4, and trehazolin, the last one being the most potent. Trehazolin is used to control blight sheath of rice, caused by the plant pathogenic fungus Rhizoctonia solani, and it thus has potential fungicidal activity.12 15... 

Deoxynojirimycin (DNJ, 1) was originally prepared by catalytic hydrogenation of nojirimycin, which was discovered as the first glucose-mimicking antibiotic produced by Streptomyces spp., with a platinum catalyst or by chemical reduction with NaBH4 [5,6]. Later it was isolated from the root bark of mulberry trees and called moranoline [7]. DNJ is also produced by many strains in the genera Bacillus and Streptomyces [8,9]. 

Ve were unaware at this time that Japanese workers had isolated from certain mulberry (Morns) spp. a compound (Figure 2) being an epimer of 1 at C3 which they named moranoline (l). It was later also found in bacteria (12-13) and described as deoxynojirimycin, the name which now prevails. This compound, 2, is an analogue of... 

Deoxynojirimycin (2) has been isolated from mulberry root bark plants of the genus Moms Mori and named moranoline Moms bombycis Koidz as well... 

Polyhydroxylated piperidines from natural sources, which have structures and shapes resembling monosaccharides have been found as a -glycosidase inhibitors. They competitively inhibit glycosidases whose substrates they most closely resemble. 1-Deoxynojirimycin (moranoline) (98 1), was isolated from Mori Cortex (root bark of the mulberry tree, Morus bombycis (Moraceae)), leaves of Jacobinia suberecta (Acanthaceae)... 

Previously, tin-ketyl radicals have been added to alkenes only in an intramolecular fashion. [9] In recent publications, however, pinacols and amino alcohols have been prepared by cyclisation of dicarbonyl compounds [10] or keto-oximes [11] with tributyltin hydride. Cyclisation of 1,5-ketoaldehydes 1 and 1,5-dialdehydes with tributyltin hydride yields cw-diols 2 with excellent stereoselectivities, whereas the keto-oxime 4 with four benzyloxy-substituents affords a 58 42 cis trans) mixture. The tran -product was transformed in two more steps to the potent glycosidase inhibitor 1-deoxynojirimycin (6). [lib] The reversibility of both the addition of the tributyltin-radical to the carbonyl group and the intramolecular radical C-C bond formation is believed to be responsible for the high selectivity in the formation of 2. In the cyclisation of 1,5-pentanedial the unhydrolyzed coupling product 3 could be isolated, therefore providing evidence for a new mechanistic variant of the pinacol reaction, in which only 1.2 equivalent of the reducing agent are necessary. 

The synthesis of amino-alditol derivatives of naturally occurring hydrolysable tannins is mentioned in Chapter 7 and the preparation of some C-6 and C-7 analogues of lV-acetyl-6-amino-2,6-dideoxyneuraminic acid as well as the isolation and synthesis of the fungal metabolite nectrisine are covered in Chapter 9. The synthesis of 4-0-(p-D-galactopyranosyl) derivatives of deoxynojirimycin can be found in Chapter 3 and castanospermine derivatives are covered in Chapter 24. 

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... 

Subsequent calystegine isolations followed enrichment schemes that were developed for the isolation of other polyhydroxy alkaloids, such as swainsonine (5) and 1-deoxynojirimycin (6) from S. canescens (Fabaceae) (7) and from Streptomyces strains (31), respectively. Due to the hydrophilicity and the basic nature of those alkaloids, they were purified from aqueous extracts by a sequence of ion exchange resin columns that were designed to bind the alkaloids as cations, or to adsorb contaminating anions, while the alkaloids were eluted with water (Figure 3, method 2). An overview of the procedures was expertly summarised by Fellows and Fleet (32). Calystegines of the A-group are the most difficult to... 

DNJ - deoxynojirimycin, first shown as microbial metabolite, was found in roots of Moms spp (Moraceae) (77). It is clear that this compoimd can be seen as an azapyranose analog of glucose. The respective mannose analog DMJ -deoxymannojirimycin, has been isolated from seeds of the tropical legume Lonchocarpus sericeus 12). DNJ and DMJ are inhibitors of a-glucosidase and mannosidase respectively. 

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