RESUMO
A collection of new reversible glycosidase inhibitors of the iminoalditol type featuring N-substituents containing perfluorinated regions has been prepared for evaluation of physicochemical, biochemical and diagnostic properties. The vast variety of feasible oligofluoro moieties allows for modular approaches to customised structures according to the intended applications, which are influenced by the fluorine content as well as the distance of the fluorous moiety from the ring nitrogen. The first examples, in particular in the D-galacto series, exhibited excellent inhibitory activities. A preliminary screen with two human cell lines showed that, at subinhibitory concentrations, they are powerful pharmacological chaperones enhancing the activities of the catalytically handicapped lysosomal D-galactosidase mutants associated with GM1 gangliosidosis and Morquio B disease.
Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Galactosidases/antagonistas & inibidores , Gangliosidose GM1/tratamento farmacológico , Álcoois Açúcares/química , Álcoois Açúcares/farmacologia , Linhagem Celular , Café/enzimologia , Inibidores Enzimáticos/uso terapêutico , Escherichia coli/enzimologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Galactosidases/metabolismo , Halogenação , Humanos , Iminas/química , Iminas/farmacologia , Iminas/uso terapêutico , Rhizobium/enzimologia , Álcoois Açúcares/uso terapêuticoRESUMO
N-Alkylation at the ring nitrogen of the D-galactosidase inhibitor 1-deoxygalactonojirimycin with a functionalised C 6alkyl chain followed by modification with different aromatic substituents provided lipophilic 1-deoxygalactonojirimycin derivatives which exhibit inhibitory properties against ß-glycosidases from E. coli and Agrobacterium sp. as well as green coffee bean α-galactosidase. In preliminary studies, these compounds also showed potential as chemical chaperones for GM1-gangliosidosis related ß-galactosidase mutants.
RESUMO
G(M1)-gangliosidosis (GM1) and Morquio B disease (MBD) are rare lysosomal storage disorders caused by mutations in the gene GLB1. Its main gene product, human acid beta-galactosidase (beta-Gal) degrades two functionally important molecules, G(M1)-ganglioside and keratan sulfate in brain and connective tissues, respectively. While GM1 is a severe, phenotypically heterogenous neurodegenerative disorder, MBD is a systemic bone disease without effects on the central nervous system. A MBD-specific mutation, p.W273L, was shown to produce stable beta-Gal precursors, normally transported and processed to mature, intralysosomal beta-Gal. In accordance with the MBD phenotype, elevated residual activity against G(M1)-ganglioside, but strongly reduced affinity towards keratan sulfate was found. Most GM1 alleles, in contrast, were shown to affect precursor stability and intracellular transport. Specific alleles, p.R201C and p.R201H result in misfolded, unstable precursor proteins rapidly degraded by endoplasmic reticulum-associated protein degradation (ERAD). They may therefore be sensitive to stabilization by small molecules which bind at the active site and provide proper conformation. Thus the stabilized protein may escape from ERAD processes, and reach the lysosomes in an active state, as proposed for enzyme enhancement therapy (EET). This paper demonstrates that a novel iminosugar, DLHex-DGJ, has potent effects as competitive inhibitor of human acid beta-galactosidase in vitro, and describes its effects on activity, protein expression, maturation and intracellular transport in vivo in 13 fibroblasts lines with GLB1 mutations. Beside p.R201C and p.R201H, two further alleles, p.C230R and p.G438E, displayed significant sensitivity against DLHex-DGJ, with an increase of catalytic activity, and a normalization of transport and lysosomal processing of beta-Gal precursors.
Assuntos
1-Desoxinojirimicina/análogos & derivados , Gangliosidose GM1/tratamento farmacológico , Mucopolissacaridose IV/tratamento farmacológico , 1-Desoxinojirimicina/química , 1-Desoxinojirimicina/farmacocinética , 1-Desoxinojirimicina/farmacologia , Alelos , Linhagem Celular , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Gangliosidose GM1/genética , Gangliosidose GM1/metabolismo , Humanos , Chaperonas Moleculares/química , Chaperonas Moleculares/farmacocinética , Chaperonas Moleculares/farmacologia , Mucopolissacaridose IV/genética , Mucopolissacaridose IV/metabolismo , Mutação , beta-Galactosidase/antagonistas & inibidores , beta-Galactosidase/genética , beta-Galactosidase/metabolismoRESUMO
Cyclisation by double reductive amination of 2-acetamino-2-deoxy-D-xylo-hexos-5-ulose with N-2 protected L-lysine derivatives provided 2-acetamino-1,2-dideoxynojirimycin derivatives without any observable epimer formation at C-5. Modifications on the lysine moiety gave access to lipophilic derivatives that exhibited improved hexosaminidase inhibitory activities.
RESUMO
Cyclization by double reductive amination of L-arabino-hexos-5-ulose with suitably protected D- as well as L-lysine derivatives provided 1-deoxygalactonojirimycin lysine hybrids without any observable epimer formation at C-5. Modifications on the lysine moiety by acylation gave access to lipophilic derivatives which exhibited excellent D-galactosidase inhibitory activities.
Assuntos
1-Desoxinojirimicina/química , Inibidores Enzimáticos/síntese química , Galactosidases/antagonistas & inibidores , Lisina/química , Acilação , Quimera , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Galactosidases/metabolismo , CinéticaRESUMO
Three typical glycosidase-inhibiting iminoalditols were attached to a polyamine surface displayed on a silicon chip. Exposure to a representative beta-glucosidase revealed selective binding events reflecting the different structural features of the inhibitors probed in this study. This provides a proof-of-concept for the successful exploitation of microarrays of typical reversible glycosidase inhibitors of the iminosugar family.
Assuntos
Inibidores Enzimáticos/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Glicosídeo Hidrolases/metabolismo , Imino Açúcares/química , Imino Açúcares/farmacologia , Análise em Microsséries , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Rhizobium/enzimologiaRESUMO
Iminosugars, featuring a basic nitrogen at the hetero atom position in carbohydrate rings, gain increasing interest in the search for novel approaches towards cancer drug development. This compound class is known as competitive inhibitors of carbohydrate manipulation enzymes, such as glycosidases, which are involved in tumor cell invasion and migration. Such enzymes are also responsible for the attachment of oligosaccharides to the cell surface of tumor cells, displayed as glycoproteins, glycolipids, and proteoglycans, which play an important role in malignant phenotype and tumor growth. Furthermore, cancer cells show an extremely active lysosomal system which is reflected by enhancement of glycoprotein turnover. Iminosugars were found to interact with glycosyl hydrolases responsible for this kind of action in cancer cells and thus open a new compound class in the research field of finding new anti-cancer activities. This review will focus on the role of iminosugars in cancer therapy and will give an overview of their properties.
Assuntos
Antineoplásicos/uso terapêutico , Glicosídeo Hidrolases/antagonistas & inibidores , Imino Açúcares/uso terapêutico , Neoplasias/tratamento farmacológico , Oligossacarídeos/metabolismo , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Desenho de Fármacos , Humanos , Imino Açúcares/síntese química , Imino Açúcares/química , Estrutura Molecular , Neoplasias/enzimologia , Neoplasias/metabolismoRESUMO
Cyclization by double reductive amination of D-xylo-hexos-5-ulose with the terminal amino group of alpha-N-Boc-lysine methyl ester gave a 4:1-mixture of (1'R)-N-methoxycarbonyl-(1-N-Boc-amino)pentyl-1-deoxynojirimycin and the corresponding L-ido epimer whereas D-lyxo-hexos-5-ulose furnished the desired N-alkylated 1-deoxymannojirimycin derivative without any observable epimer formation at C-5. By subsequent modification of the lysine moiety, additional chain-extended derivatives as well as fluorescent compounds were obtained. All fluorescent iminoalditol-amino acid hybrids prepared in this study exhibited glycosidase inhibitory activities better than or comparable to the parent compounds'.
Assuntos
Aminoácidos/química , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Iminas , Álcoois Açúcares/química , Aminoácidos/farmacologia , Inibidores Enzimáticos/química , Glucosidases/antagonistas & inibidores , Indicadores e Reagentes , Cinética , Manosidases/antagonistas & inibidores , Modelos Moleculares , Álcoois Açúcares/síntese química , Álcoois Açúcares/farmacologiaRESUMO
1,4-Anhydro-D-fructose and 1,4-anhydro-D-tagatose were prepared from 1,2-O-isopropylidene-D-glucofuranose via the common intermediate 3,5,6-tri-O-benzyl-D-glucitol. The title compounds may be interesting anti-oxidants and feature activities akin to their natural pyranoid counterpart, 1,5-anhydro-D-fructose.
Assuntos
Frutose/análogos & derivados , Antioxidantes/química , Antioxidantes/farmacologia , Frutose/síntese química , Frutose/químicaRESUMO
1,5-Dideoxy-1,5-imino-D-glucitol, the corresponding D-manno and L-ido epimers as well as the powerful beta-glucosidase inhibitor isofagomine were N-alkylated with di-, tri-, as well as tetraethylene glycol derived straight chain spacer arms by a set of simple standard procedures. The terminal functional groups of the spacer arms, primary amines, were employed to introduce fluorescent dansyl moieties. Resulting derivatives showed glycosidase inhibitory activities comparable to those of the parent compounds'.
Assuntos
Corantes Fluorescentes/química , Glicosídeo Hidrolases/antagonistas & inibidores , Imino Açúcares/química , Álcoois Açúcares/química , Corantes Fluorescentes/farmacologia , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/genética , Imino Piranoses/farmacologia , Imino Açúcares/farmacologia , Cinética , Piperidinas/farmacologia , Rhizobium/enzimologia , Álcoois Açúcares/farmacologiaRESUMO
Glucosidase inhibitors alpha-D-glucopyranosyl-(1-->4)-1-deoxynojirimycin and beta-D-glucopyranosyl-(1-->4)-1-deoxynojirimycin were prepared from maltose and cellobiose, respectively, via the corresponding 5,6-eno derivatives, their epoxidation and the subsequent double reductive amination of the resulting 5-uloses. In both cases, the reported route is the first chemical synthesis not based on enzymatic glucosyl transfer.
Assuntos
Glucosamina/análogos & derivados , Glucosamina/síntese química , Celobiose/química , Glucose/química , Inibidores de Glicosídeo Hidrolases , Glicosilação , Maltose/químicaRESUMO
A range of new C-1 modified derivatives of the powerful glucosidase inhibitor 2,5-dideoxy-2,5-imino-D-mannitol has been synthesised and their biological activities probed with the beta-glucosidase from Agrobacterium sp. Ki values are compared with those of previously prepared close relatives. Findings suggest dramatic effects exerted by the aglycon binding site on substrate/inhibitor binding.