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1.
A versatile and concise synthesis of N-alkylated 1,4-dideoxy-1,4-imino-D-arabinitol and 1,4-dideoxy-1,4-imino-L-xylitol derivatives is described. These were prepared using pseudohemiketal lactams as key intermediates, which in turn were obtained from sucrose. The key intermediates were prepared by a diastereospecific tandem reaction which facilitated the introduction of various substituents on the nitrogen atom of the iminosugars. 相似文献
2.
G.W.J. Fleet S.J. Nicholas P.W. Smith S.V. Evans L.E. Fellows R.J. Nash 《Tetrahedron letters》1985,26(26):3127-3130
The syntheses of 1,4-dideoxy-1,4-imino-D-lyxitol (3), 1,4-dideoxy-1,4-imino-d-arabinitol (4) and 1,4-dideoxy-1,4-imino-l-arabinitol (5) are reported; (3) is a potent competitive inhibitor of α-galactosidase (green coffee beans) and (4) a competitive inhibitor of α-glucosidase (Brewer's yeast) suggesting that iminopentitols have considerable potential as glycosidase inhibitors. (4) was found to be identical to an alkaloid recently isolated from . 相似文献
3.
《Tetrahedron》1988,44(9):2649-2655
The syntheses of 1,4-dideoxy-l,4-imino-L-ribitol and of 1,4-dideoxy-l,4-imino-D-talitol from D-mannose are described. 1,4-Dideoxy-l,4-imino-D-talitol is a specific and competitive inhibitor of human liver α-mannosidase and also blocks the lysosomal catabolism of asparigine-linked glycans of glycoproteins . 相似文献
4.
5.
Shanmugam Thiyagarajan Linda Gootjes Willem Vogelzang Jing Wu Jacco van Haveren Daan S. van Es 《Tetrahedron》2011,67(2):383-389
An efficient route towards the synthesis of 2,5-diamino-2,5-dideoxy-1,4-3,6-dianhydroiditol 4 has been developed resulting in significant improvements in both isolated yields and purity when compared to literature procedures. As a consequence, resin-grade 2,5-diamino-2,5-dideoxy-1,4-3,6-dianhydroiditol 4 has become available for laboratory scale step-growth polymer synthesis. Additionally, an interesting renewable chiral 2-amino-2-deoxy-1,4-3,6-dianhydroiditol 10, has been isolated. 相似文献
6.
《Tetrahedron: Asymmetry》2007,18(2):282-289
The synthesis of l-DIM [1,4-dideoxy-1,4-imino-l-mannitol] and of 1,4-imino-d-glycero-l-talo-heptitol from d-glycero-d-gulo-heptono-1,4-lactone depends on the use of pentan-3-one to form two five ring ketals as described by Burke, rather than the formation of one five ring and one six ring ketal formed with acetone. l-DIM, the enantiomer of the potent α-d-mannosidase inhibitor DIM [1,4-dideoxy-1,4-imino-d-mannitol] is a good inhibitor of naringinase (an α-l-rhamnosidase) with a Ki of 3.63 μM. 1,4-Imino-d-glycero-l-talo-heptitol is a moderate inhibitor of naringinase. 相似文献
7.
A highly efficient method for the synthesis of 1,4-dideoxy-1,4-imino-d- and l-arabinitol (d-AB1, 1 and l-AB1, 3) and 1,4-dideoxy-1,4-imino-d- and l-xylitol (d-DIX, 2 and l-DIX, 4) starting from commercially available chiral aziridines was developed. The general strategy employs a sequence involving two-carbon homologation, dihydroxylation, and regioselective aziridine ring opening/intramolecular five-membered iminosugar ring formation. The facile use of recrystallization to generate pure diastereomers makes the routes more amenable to large-scale synthesis. 相似文献
8.
The total syntheses of tetrahydroxy-LCB 1, alpha-galactosyl ceramide 2, and 1,4-dideoxy-1,4-imino-L-ribitol 3 via D-allosamine derivatives as common synthons are described here. 相似文献
9.
《Tetrahedron letters》2004,45(4):719-722
A stereodivergent synthesis of 1,4-dideoxy-1,4-imino-d-mannitol I and d-allitol III from an (S)-glyceraldimine, which is easily prepared from d-mannitol, has been achieved with overall yields of 62% and 49%, respectively. The synthesis is based on the addition of vinylmagnesium bromide to N-benzylimine 1, derived from readily available (R)-2,3-O-isopropylideneglyceraldehyde, followed by N-allylation or N-acryloylation, ring-closing metathesis and asymmetric dihydroxylation. 相似文献
10.
Carmona AT Fuentes J Robina I García ER Demange R Vogel P Winters AL 《The Journal of organic chemistry》2003,68(10):3874-3883
A new route for the preparation of four new indolizidines, (1R,2S,6S,7S,8aS)- and (1R,2S,6R,7R,8aS)-1,2,6,7-tetrahydroxyindolizidine (30 and 32) and (1S,2R,7S,8S,8aR)- and (1S,2R,7R,8R,8aR)-1,2,7,8-tetrahydroxyindolizidine (44 and 46), is reported. The synthesis is based on Knoevenagel homologation of the readily available enantiomerically pure pyrrolidin-carbaldehydes 13 and 37followed by asymmetric dihydroxylation of the subsequent alkenyl pyrrolidines and cyclization of the corresponding imino-octitols. The new indolizidines and their precursors (imino-octitols 20, 25, 26) and indolizidinones 28a and 28b have been tested for inhibitory activities toward 26 glycosidases. The enzymatic inhibition of trans-7-hydroxy-d-(-)-swainsonine (44) toward alpha-mannosidases is similar to that described for trans-7-hydroxy-l-(+)-swainsonine (11b) toward naringinase (alpha-l-rhamnosidase from Penicillium decumbens). 相似文献
11.
Otero JM Soengas RG Estévez JC Estévez RJ Watkin DJ Evinson EL Nash RJ Fleet GW 《Organic letters》2007,9(4):623-626
A novel promising strategy for the transformation of nitrosugars into branched pyrrolidines, based on double Henry reaction with formaldehyde followed by reductive ring closure, allowed the first enantiospecific synthesis of a 4-C-hydroxymethyl branched derivative of the well-known glycosidase inhibitor 1,4-dideoxy-1,4-imino-pentanol. This strategy also afforded a new route to some other interesting derivatives, such as N-hydroxy, N-propyloxy, and imino derivatives, a new kind of compounds with promising biological properties. [reaction: see text]. 相似文献
12.
1-Deoxymannojirimycin (8c) was synthesised from 2-amino-6-bromo-2,6-dideoxy-D-mannono-1,4-lactone (7) by intramolecular direct displacement of the C-6 bromine employing non-aqueous base treatment followed by reduction of the intermediate methyl ester. Likewise, using aqueous base at pH 12, ring closure took place by 5-exo attack on the 5,6-epoxide leading to 2,5-dideoxy-2,5-imino-L-gulonic acid (9b), which was reduced to 2,5-dideoxy-2,5-imino-D-glucitol (9b). The method was further applied to 2-amino-6-bromo-2,6-dideoxy-D-galacto- as well as D-talo-1,4-lactones (14 and 15). However, only the corresponding six-membered ring 1,5-iminuronic acid mimetics, namely (2R,3R,4S,5R)-3,4,5-trihydroxypipecolic acid (2,6-dideoxy-2,6-imino-D-galactonic acid, 16) and (2S,3R,4S,5R)-3,4,5-trihydroxypipecolic acid (2,6-dideoxy-2,6-imino-D-talonic acid, 17), were obtained. The corresponding enantiomers, L-galacto- as well as L-talo-2-amino-6-bromo-2,6-dideoxy-1,4-lactones ent-14 and ent-15, reacted accordingly to give the D-galacto- and L-altro-1,5-iminuronic acid mimetics, (2S,3S,4R,5S)-3,4,5-trihydroxypipecolic acid (2,6-dideoxy-2,6-imino-L-galactonic acid, ent-16) and (2R,3S,4R,5S)-3,4,5-trihydroxypipecolic acids (2,6-dideoxy-2,6-imino-L-talonic acid, ent-17), respectively. 相似文献
13.
[reaction: see text] Various alpha-C-substituted 1,4-dideoxy-1,4-imino-d-galactitols were prepared efficiently from 1-O-acetyl-2,3,5,6-tetra-O-benzyl-d-glucofuranose by a four-step sequence involving as the key step the highly syn-selective TMSOTf-catalyzed addition of silylated nucleophiles to a glycofuranosylamine. Cross-metathesis of the alpha-C-allylated iminogalactofuranose derivative with an original uridin-5'-yl vinylphosphonate led to novel UDP-galactofuranose mimics. Such compounds are of interest as potential inhibitors of the mycobacterial galactan biosynthesis pathway. 相似文献
14.
《Tetrahedron: Asymmetry》2002,12(24):3409-3415
Asymmetric synthesis of 1,4-dideoxy-1,4-imino-d-ribitol was achieved utilizing the stereoselective addition of allylphenylsulfone to a chiral N-sulfinyl-2-furfuryl imine and ring-closing metathesis reactions as key steps. 相似文献
15.
Walter A. Szarek Dolatrai M. Vyas Barbara Achmatowicz 《Journal of heterocyclic chemistry》1975,12(1):123-127
The two regioisomers 6-chloro-9-(1, 4-oxathian-3-yl)-9H-purine ( 5 ) and 6-chloro-9-(1,4-oxathian-2-yl)-9H-purine ( 6 ) were obtained when 3-acetoxy-1,4-oxathiane ( 3 ) was subjected to the acid-catalyzed fusion procedure; compound 3 was prepared by a Pummerer reaction with 1,4-oxathiane 4-oxide ( 2 ). The nucleoside analog 6 could he converted into the adenine derivative 7 and 9-(1,4-oxathian-2-yl)-9H-purine-6(1H)thione ( 8 ). The following nucleoside analogs have also been synthesized: 6-chloro-9-(1,4-dithian-2-yl)-9H-purine ( 13 ), 9-(1,4-dithian-2-yl)adenine ( 14 ), 9-(1,4-dithian-2-yl)-9H-purine-6(1H)thione ( 15 ), and 6-chloro-9-(1,4-dioxan-2-yl)-9H-purine ( 18 ). 相似文献
16.
Thomas B. Mercer Sarah F. Jenkinson Barbara Bartholomew Robert J. Nash Saori Miyauchi Atsushi Kato George W.J. Fleet 《Tetrahedron: Asymmetry》2009,20(20):2368-2373
Benzhydryl protection by diphenyldiazomethane of an alcohol in enantiomeric base-sensitive ribonolactones allows short efficient syntheses of 1,4-dideoxy-1,4-imino-d-lyxitol (DIL) and of 1,4-dideoxy-1,4-imino-l-lyxitol (LIL). DIL showed potent [Ki = 0.13 μM]—and LIL showed weak [Ki = 113 μM]—competitive inhibition of α-d-galactosidase. Both enantiomers N-benzyl-DIL [Ki = 64 μM] and N-benzyl-LIL [Ki = 13 μM] were moderate competitive inhibitors of naringinase, an α-l-rhamnosidase. 相似文献
17.
[reaction: see text] A highly regioselective borane-reductive ring opening of the 4,6-O-benzylidene-D-hexopyranosides to the corresponding 6-alcohols in excellent yields at room temperature via various metal trifluoromethanesulfonates as catalysts is described here. Its application in the synthesis of 1,4-dideoxy-1,4-imino-L-xylitol is also highlighted. 相似文献
18.
Asymmetric synthesis of 1,4-dideoxy-1,4-imino-
-ribitol was achieved utilizing the stereoselective addition of allylphenylsulfone to a chiral N-sulfinyl-2-furfuryl imine and ring-closing metathesis reactions as key steps. 相似文献
19.
1,4-thiazepines, 1,4-benzothiazepin-5-ones,and 1,4-benzothioxepin orthoamides via multicomponent reactions of isocyanides 总被引:2,自引:0,他引:2
Marcaccini S Miguel D Torroba T García-Valverde M 《The Journal of organic chemistry》2003,68(8):3315-3318
The intramolecular Ugi four-component condensation between 6-oxo-4-thiacarboxylic acids, benzylamines, and cyclohexyl isocyanide gave hexahydro-1,4-thiazepin-5-ones and 1,4-benzothiazepin-5-ones, in some cases with high stereoselectivity, and the intramolecular Passerini three-component reaction, in the presence of catalytic amine, gave tetracyclic 1,4-benzothioxepin orthoamides. 相似文献
20.
A Pd(II)-catalyzed cyclization of difunctional allylic N-tosyl carbamates in the presence of halide ions was developed with high regio- and diastereoselectivity. The reaction involves aminopalladation of alkene and beta-heteroatom elimination to regenerate Pd(II) species. When the readily available homochiral alcohols were used as substrates, highly optically active 4-vinyl-2-oxazolidinones were easily obtained. The utility of this method was exemplified by the convenient synthesis of 1,4-dideoxy-1,4-imino-L-xylitol. 相似文献