RESUMO
The conventional approach to developing light-sensitive glycosidase activity regulators, involving the combination of a glycomimetic moiety and a photoactive azobenzene module, results in conjugates with differences in glycosidase inhibitory activity between the interchangeable E and Z-isomers at the azo group that are generally below one-order of magnitude. In this study, we have exploited the chemical mimic character of sp2-iminosugars to access photoswitchable p- and o-azobenzene α-O-glycosides based on the gluco-configured representative ONJ. Notably, we achieved remarkably high switching factors for glycosidase inhibition, favoring either the E- or Z-isomer depending on the aglycone structure. Our data also indicate a correlation between the isomeric state of the azobenzene module and the selectivity towards α- and ß-glucosidase isoenzymes. The most effective derivative reached over a 103-fold higher inhibitory potency towards human ß-glucocerebrosidase in the Z as compared with the E isomeric form. This sharp contrast is compatible with ex-vivo activation and programmed self-deactivation at physiological temperatures, positioning it as a prime candidate for pharmacological chaperone therapy in Gaucher disease. Additionally, our results illustrate that chemical tailoring enables the engineering of photocommutators with the ability to toggle inhibition between α- and ß-glucosidase enzymes in a reversible manner, thus expanding the versatility and potential therapeutic applications of this approach.
Assuntos
Compostos Azo , Inibidores Enzimáticos , Glicosídeo Hidrolases , Glicosídeos , Imino Açúcares , Humanos , Compostos Azo/química , Compostos Azo/farmacologia , Compostos Azo/síntese química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Glicosídeo Hidrolases/antagonistas & inibidores , Glicosídeo Hidrolases/metabolismo , Glicosídeos/química , Glicosídeos/farmacologia , Glicosídeos/síntese química , Imino Açúcares/química , Imino Açúcares/farmacologia , Imino Açúcares/síntese química , Luz , Estrutura Molecular , Relação Estrutura-Atividade , Glucosilceramidase/química , Glucosilceramidase/metabolismo , Glucosilceramidase/farmacologiaRESUMO
A remarkable enhancer of human glucocerebrosidase enzyme (GCase) was identified among a set of dihydroazulene-tagged iminosugars. An unprecedented 3.9-fold increase in GCase activity was detected on fibroblasts bearing the homozygous L444P mutation, which is frequently associated with neuronopathic Gaucher forms, and which commonly results refractory to chaperone-induced refolding.
Assuntos
Glucosilceramidase , Mutação , Humanos , Glucosilceramidase/metabolismo , Glucosilceramidase/genética , Glucosilceramidase/antagonistas & inibidores , Imino Açúcares/química , Imino Açúcares/farmacologia , Imino Açúcares/síntese química , Imino Açúcares/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Doença de Gaucher/genética , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/metabolismo , Estrutura MolecularRESUMO
We report the synthesis of seven-membered iminosugars derived from a 3S-acetamido-4R,5R,6S-trihydroxyazepane scaffold and their evaluation as inhibitors of functionally related exo-N-acetylhexosaminidases including human O-GlcNAcase (OGA), human lysosomal ß-hexosaminidase (HexAB), and Escherichia coli NagZ. Capitalizing on the flexibility of azepanes and the active site tolerances of hexosaminidases, we explore the effects of epimerization of stereocenters at C-3, C-5 and C-6 and C-alkylation at the C-2 or C-7 positions. Accordingly, epimerization at C-6 (L-ido) and at C-5 (D-galacto) led to selective HexAB inhibitors whereas introduction of a propyl group at C-7 on the C-3 epimer furnished a potent NagZ inhibitor.
Assuntos
Acetilglucosaminidase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Imino Açúcares/farmacologia , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , Acetilglucosaminidase/metabolismo , Alquilação , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Escherichia coli/enzimologia , Humanos , Imino Açúcares/síntese química , Imino Açúcares/química , Conformação Molecular , beta-N-Acetil-Hexosaminidases/metabolismoRESUMO
Most enveloped viruses rely on the host cell endoplasmic reticulum (ER) quality control (QC) machinery for proper folding of glycoproteins. The key ER α-glucosidases (α-Glu) I and II of the ERQC machinery are attractive targets for developing broad-spectrum antivirals. Iminosugars based on deoxynojirimycin have been extensively studied as ER α-glucosidase inhibitors; however, other glycomimetic compounds are less established. Accordingly, we synthesized a series of N-substituted derivatives of valiolamine, the iminosugar scaffold of type 2 diabetes drug voglibose. To understand the basis for up to 100,000-fold improved inhibitory potency, we determined high-resolution crystal structures of mouse ER α-GluII in complex with valiolamine and 10 derivatives. The structures revealed extensive interactions with all four α-GluII subsites. We further showed that N-substituted valiolamines were active against dengue virus and SARS-CoV-2 in vitro. This study introduces valiolamine-based inhibitors of the ERQC machinery as candidates for developing potential broad-spectrum therapeutics against the existing and emerging viruses.
Assuntos
Antivirais/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Imino Açúcares/farmacologia , Inositol/análogos & derivados , alfa-Glucosidases/metabolismo , Animais , Antivirais/síntese química , Antivirais/metabolismo , Sítios de Ligação , Chlorocebus aethiops , Cristalografia por Raios X , Vírus da Dengue/efeitos dos fármacos , Retículo Endoplasmático/enzimologia , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/metabolismo , Humanos , Imino Açúcares/síntese química , Imino Açúcares/metabolismo , Inositol/síntese química , Inositol/metabolismo , Inositol/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Ligação Proteica , SARS-CoV-2/efeitos dos fármacos , Células Vero , alfa-Glucosidases/químicaRESUMO
We have used the Cu(i)-catalyzed azide-alkyne Huisgen cycloaddition reaction to obtain two families of bivalent heterodimers where tacrine is connected to an azasugar or iminosugar, respectively, via linkers of variable length. The heterodimers were investigated as cholinesterase inhibitors and it was found that their activity increased with the length of the linker. Two of the heterodimers were significantly stronger acetylcholinesterase inhibitors than the monomeric tacrine. Molecular modelling indicated that the longer heterodimers fitted better into the active gorge of acetylcholinesterase than the shorter counterparts and the former provided more efficient simultaneous interaction with the tryptophan residues in the catalytic anionic binding site (CAS) and the peripheral anionic binding site (PAS).
Assuntos
Inibidores da Colinesterase/química , Imino Açúcares/química , Tacrina/química , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Animais , Butirilcolinesterase/química , Butirilcolinesterase/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/metabolismo , Electrophorus , Ensaios Enzimáticos , Cavalos , Imino Açúcares/síntese química , Imino Açúcares/metabolismo , Cinética , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação Proteica , Relação Estrutura-Atividade , Tacrina/síntese química , Tacrina/metabolismo , TermodinâmicaRESUMO
Cyclopropanated iminosugars have a locked conformation that may enhance the inhibitory activity and selectivity against different glycosidases. We show the synthesis of new cyclopropane-containing piperidines bearing five stereogenic centers from natural amino acids l-serine and l-alanine. Those prepared from the latter amino acid may mimic l-fucose, a natural-occurring monosaccharide involved in many molecular recognition events. Final compounds prepared from l-serine bear S configurations on the C5 position. The synthesis involved a stereoselective cyclopropanation reaction of an α,ß-unsaturated piperidone, which was prepared through a ring-closing metathesis. The final compounds were tested as possible inhibitors of different glycosidases. The results, although, in general, with low inhibition activity, showed selectivity, depending on the compound and enzyme, and in some cases, an unexpected activity enhancement was observed.
Assuntos
Aminoácidos/química , Produtos Biológicos/química , Inibidores Enzimáticos/farmacologia , Imino Açúcares/farmacologia , Animais , Café/enzimologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Geobacillus stearothermophilus/enzimologia , Glicosídeo Hidrolases/antagonistas & inibidores , Glicosídeo Hidrolases/metabolismo , Caracois Helix/enzimologia , Imino Açúcares/síntese química , Imino Açúcares/química , Estrutura Molecular , Phaseolus/enzimologiaRESUMO
In the effort to improve the antimicrobial activity of iminosugars, we report the synthesis of lipophilic iminosugars 10a-b and 11a-b based on the one-pot conjugation of both enantiomeric forms of N-butyldeoxynojirimycin (NBDNJ) and N-nonyloxypentyldeoxynojirimycin (NPDNJ) with cholesterol and a succinic acid model linker. The conjugation reaction was tuned using the established PS-TPP/I2/ImH activating system, which provided the desired compounds in high yields (94-96%) by a one-pot procedure. The substantial increase in the lipophilicity of 10a-b and 11a-b is supposed to improve internalization within the bacterial cell, thereby potentially leading to enhanced antimicrobial properties. However, assays are currently hampered by solubility problems; therefore, alternative administration strategies will need to be devised.
Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Imino Açúcares/síntese química , Imino Açúcares/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Staphylococcus aureus/crescimento & desenvolvimento , Relação Estrutura-AtividadeRESUMO
The first stereocontrolled total synthesis of iminosugar 1,4-dideoxy-1,4-imino-D-iditol is described. The key step in our approach was the double diastereoselection in the asymmetric dihydroxylation (AD) of suitable optically active olefin, the chiral vinyl azido alcohol 9. Performing the AD using the most common Cinchona alkaloids as ligands enabled us to identify the ligand of choice for the stereodivergent synthesis of 1,4-dideoxy-1,4-imino-D-iditol and 1,4-dideoxy-1,4-imino-D-galactitol. These type of iminosugars, both natural and unnatural, are intensively studied for their promising chemotherapeutic properties against viral infections, diabetes, cancer, and tuberculosis.
Assuntos
Imino Açúcares/síntese química , Imino Açúcares/química , Estrutura Molecular , EstereoisomerismoRESUMO
A strategy towards the synthesis of three different target molecules, namely 1,4-dideoxy-1,4-imino-l-xylitol, deacetyl (+)-anisomycin and amino-substituted piperidine iminosugars, molecules of potential biological and medicinal significance, is reported from a common amino-vicinal diol intermediate derived from tri-O-benzyl-d-glucal. Construction of the key pyrrolidine ring present in 1,4-dideoxy-1,4-imino-l-xylitol and (+)-anisomycin was a consequence of thermodynamically driven concomitant intramolecular nucleophilic addition reaction of the amino group to the resultant aldehyde obtained by oxidative cleavage of the amino-vicinal diol. Alternatively, double nucleophilic substitution on an amino-diol, after mesylation, with various amines delivered amino-substituted piperidine iminosugars in good yields.
Assuntos
Anisomicina/síntese química , Imino Açúcares/síntese química , Piperidinas/síntese química , Xilitol/análogos & derivados , Anisomicina/química , Imino Furanoses/síntese química , Imino Furanoses/química , Imino Açúcares/química , Conformação Molecular , Piperidinas/química , Estereoisomerismo , Xilitol/síntese química , Xilitol/químicaRESUMO
The synthesis of a chemical library of multimeric pyrrolidine-based iminosugars by incorporation of three pairs of epimeric pyrrolidine-azides into different alkyne scaffolds via CuAAC is presented. The new multimers were evaluated as inhibitors of two important therapeutic enzymes, human α-galactosidase A (α-Gal A) and lysosomal ß-glucocerebrosidase (GCase). Structure-activity relationships were established focusing on the iminosugar inhitope, the valency of the dendron and the linker between the inhitope and the central scaffold. Remarkable is the result obtained in the inhibition of α-Gal A, where one of the nonavalent compounds showed potent inhibition (0.20 µM, competitive inhibition), being a 375-fold more potent inhibitor than the monovalent reference. The potential of the best α-Gal A inhibitors to act as pharmacological chaperones was analyzed by evaluating their ability to increase the activity of this enzyme in R301G fibroblasts from patients with Fabry disease, a genetic disorder related with a reduced activity of α-Gal A. The best enzyme activity enhancement was obtained for the same nonavalent compound, which increased 5.2-fold the activity of the misfolded enzyme at 2.5 µM, what constitutes the first example of a multivalent α-Gal A activity enhancer of potential interest in the treatment of Fabry disease.
Assuntos
Inibidores Enzimáticos/farmacologia , Doença de Fabry/tratamento farmacológico , Glucosilceramidase/antagonistas & inibidores , Imino Açúcares/farmacologia , Pirrolidinas/farmacologia , alfa-Galactosidase/antagonistas & inibidores , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Doença de Fabry/metabolismo , Glucosilceramidase/metabolismo , Humanos , Imino Açúcares/síntese química , Imino Açúcares/química , Estrutura Molecular , Pirrolidinas/síntese química , Pirrolidinas/química , Relação Estrutura-Atividade , alfa-Galactosidase/metabolismoRESUMO
Radical thiol-ene coupling was exploited for the first time to prepare imino-disaccharides and multivalent iminosugars starting from sugar thiols and iminosugar alkenes or iminosugar thiols and tetra-allylated calixarene, respectively.
Assuntos
Alcenos/química , Dissacarídeos/síntese química , Imino Açúcares/síntese química , Compostos de Sulfidrila/química , Alcenos/efeitos da radiação , Calixarenos/química , Calixarenos/efeitos da radiação , Radicais Livres/química , Compostos de Sulfidrila/efeitos da radiação , Raios UltravioletaRESUMO
A series of tricyclic benzimidazole-iminosugars 1(a-f) and 2(a-f) were synthesized and evaluated for their their inhibitory activities against five glycosidases. The synthesis initiated from the benzyl protected sugar (aldehyde) 5 that reacted with 1,2-diaminobenzene to afford aldo-benzimidazole 6 by the iodine-induced oxidative condensation. Then, tricyclic compound 7 was obtained in high yields of 73%-87% by the key Mitsunobu reaction through intramolecular cyclization of the unprotected OH and the NH in 6. After removal of the benzyl group in CF3SO3H, the target tricyclic benzimidazole-iminosugars 1 and 2 were achieved. The protocol was effective for the preparation of the tricyclic iminosugar in satisfactory yield. The results of the glycosidase inhibitory activities of 1 and 2 showed that three compounds derived from d-ribose exhibited specific and good inhibitory effects on ß-glucosidase. Among them, 1e-1 was the best one with IC50 value of 5.37⯵M. All hydroxyl groups on ß-position would be favourable to the inhibitory activity of such tricyclic benzimidazole-iminosugars against ß-glucosidase.
Assuntos
Benzimidazóis/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Glicosídeo Hidrolases/antagonistas & inibidores , Imino Açúcares/química , Imino Açúcares/síntese química , Configuração de Carboidratos , Técnicas de Química Sintética , Inibidores Enzimáticos/farmacologia , Imino Açúcares/farmacologia , Concentração Inibidora 50 , Modelos Moleculares , Relação Estrutura-AtividadeRESUMO
Immunomodulatory glycolipids, among which α-galactosylceramide (KRN7000) is an iconic example, have shown strong therapeutic potential in a variety of conditions ranging from cancer and infection to autoimmune or neurodegenerative diseases. A main difficulty for those channels is that they often provoke a cytokine storm comprising both pro- and anti-inflammatory mediators that antagonize each other and negatively affect the immune response. The synthesis of analogues with narrower cytokine secretion-inducing capabilities is hampered by the intrinsic difficulty at controlling the stereochemical outcome in glycosidation reactions, particularly if targeting the α-anomer, which seriously hampers drug optimization strategies. Here we show that replacing the monosaccharide glycone by a sp2-iminosugar glycomimetic moiety allows accessing N-linked sp2-iminosugar glycolipids (sp2-IGLs) with total α-stereocontrol in a single step with no need of protecting groups or glycosidation promotors. The lipid tail has been then readily tailored by incorporating polyfluoroalkyl segments of varied lengths in view of favouring binding to the lipid binding site of the master p38 mitogen activated protein kinase (p38 MAPK), thereby polarizing the immune response in a cell-context dependent manner. The compounds have been evaluated for their antiproliferative, anti-leishmanial and anti-inflammatory activities in different cell assays. The size of the fluorous segment was found to be critical for the biological activity, probably by regulating the aggregation and membrane-crossing properties, whereas the hydroxylation profile (gluco or galacto-like) was less relevant. Biochemical and computational data further support a mechanism of action implying binding to the allosteric lipid binding site of p38 MAPK and subsequent activation of the noncanonical autophosphorylation route. The ensemble of results provide a proof of concept of the potential of sp2-IGLs as immunoregulators.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antiprotozoários/síntese química , Antiprotozoários/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Glicolipídeos/síntese química , Glicolipídeos/química , Glicolipídeos/farmacologia , Humanos , Imino Açúcares/síntese química , Imino Açúcares/química , Imino Açúcares/farmacologia , Fatores Imunológicos/síntese química , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Testes de Sensibilidade Parasitária , Fosforilação/efeitos dos fármacos , Relação Estrutura-Atividade , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
The synthesis of multivalent pyrrolidine iminosugars via CuAAC click reaction between different pyrrolidine-azide derivatives and tri- or hexavalent alkynyl scaffolds is reported. The new multimeric compounds, together with the monomeric reference, were evaluated as inhibitors against two homologous GH1 ß-glucosidases (BglA and BglB from Paenibacillus polymyxa). The multivalent inhibitors containing an aromatic moiety in the linker between the pyrrolidine and the scaffold inhibited the octameric BglA (µM range) but did not show affinity against the monomeric BglB, despite the similarity between the active site of both enzymes. A modest multivalent effect (rp/nâ¯=â¯12) was detected for the hexavalent inhibitor 12. Structural analysis of the complexes between the monomeric and the trimeric iminosugar inhibitors (4 and 10) and BglA showed the insertion of the inhibitors at the active site of BglA, confirming a competitive mode of inhibition as indicated by enzyme kinetics. Additionally, structural comparison of the BglA/4 complex with the reported BglB/2F-glucose complex illustrates the key determinants responsible for the inhibitory effect and explains the reasons of the inhibition of BglA and the no inhibition of BglB. Potential inhibition of other ß-glucosidases with therapeutic relevance is discussed under the light of these observations.
Assuntos
Inibidores Enzimáticos/farmacologia , Imino Açúcares/farmacologia , Pirrolidinas/farmacologia , beta-Glucosidase/antagonistas & inibidores , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Imino Açúcares/síntese química , Imino Açúcares/química , Modelos Moleculares , Estrutura Molecular , Paenibacillus polymyxa/enzimologia , Pirrolidinas/síntese química , Pirrolidinas/química , Relação Estrutura-Atividade , beta-Glucosidase/isolamento & purificação , beta-Glucosidase/metabolismoRESUMO
A series of novel tricyclic quinazolinone-iminosugars 1 (a-c) were synthesized from the benzyl protected sugars through three steps. Firstly, the benzyl protected sugar (aldehyde) 5 reacted with o-aminobenzamide by the iodine-induced oxidative condensation to afford the corresponding aldo-quizanolinone 6. Secondly, through the intramolecular cyclization of the unprotected OH and the amide NH in 6, the tricyclic compounds 7 and 8 were constructed by the key Mitsunobu reaction. Finally, removal of the benzyl group gave the target tricyclic quinazolinone-iminosugars 1. The protocol was effective for the preparation of the tricyclic iminosugars in satisfactory yield. Interestingly, an unusual C-2 epimerization was observed with d-mannose and d-ribose compounds under the conditions of the Mitsunobu reaction that generated the products having the trans configuration at the C-2 and C-3 positions. Unfortunately, such tricyclic quinazolinone-iminosugars showed no inhibitory effects on the tested five glycosidases.
Assuntos
Inibidores Enzimáticos/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Imino Açúcares/farmacologia , Quinazolinonas/farmacologia , Aspergillus niger/enzimologia , Canavalia/enzimologia , Configuração de Carboidratos , Café/enzimologia , Ciclização , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Escherichia coli/enzimologia , Glicosídeo Hidrolases/metabolismo , Imino Açúcares/síntese química , Imino Açúcares/química , Prunus dulcis/enzimologia , Quinazolinonas/síntese química , Quinazolinonas/químicaRESUMO
The diffusion of type 2 diabetes (T2D) throughout the world represents one of the most important health problems of this century. Patients suffering from this disease can currently be treated with numerous oral anti-hyperglycaemic drugs, but none is capable of reproducing the physiological action of insulin and, in several cases, they induce severe side effects. Developing new anti-diabetic drugs remains one of the most urgent challenges of the pharmaceutical industry. Multi-target drugs could offer new therapeutic opportunities for the treatment of T2D, and the reported data on type 2 diabetic mice models indicate that these drugs could be more effective and have fewer side effects than mono-target drugs. α-Glucosidases and Protein Tyrosine Phosphatase 1B (PTP1B) are considered important targets for the treatment of T2D: the first digest oligo- and disaccharides in the gut, while the latter regulates the insulin-signaling pathway. With the aim of generating new drugs able to target both enzymes, we synthesized a series of bifunctional compounds bearing both a nitro aromatic group and an iminosugar moiety. The results of tests carried out both in vitro and in a cell-based model, show that these bifunctional compounds maintain activity on both target enzymes and, more importantly, show a good insulin-mimetic activity, increasing phosphorylation levels of Akt in the absence of insulin stimulation. These compounds could be used to develop a new generation of anti-hyperglycemic drugs useful for the treatment of patients affected by T2D.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucosidases/antagonistas & inibidores , Hipoglicemiantes/farmacologia , Imino Açúcares/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Diabetes Mellitus Tipo 2/metabolismo , Relação Dose-Resposta a Droga , Glucosidases/metabolismo , Células Hep G2 , Humanos , Hipoglicemiantes/síntese química , Hipoglicemiantes/química , Imino Açúcares/síntese química , Imino Açúcares/química , Conformação Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Relação Estrutura-AtividadeRESUMO
The synthesis of a library of pyrrolidine-aryltriazole hybrids through CuAAC between two epimeric dihydroxylated azidomethylpyrrolidines and differently substituted phenylacetylenes is reported. The evaluation of the new compounds as inhibitors of lysosomal ß-glucocerebrosidase showed the importance of the substitution pattern of the phenyl moiety in the inhibition. Crystallization and docking studies revealed key interactions of the pyrrolidine motif with aminoacid residues of the catalytic site while the aryltriazole moiety extended along a hydrophobic surface groove. Some of these compounds were able to increase the enzyme activity in Gaucher patient fibroblasts, acting as a new type of chemical chaperone for Gaucher disease.
Assuntos
Inibidores Enzimáticos/farmacologia , Glucosilceramidase/antagonistas & inibidores , Imino Açúcares/farmacologia , Pirrolidinas/farmacologia , Triazóis/farmacologia , Biocatálise , Linhagem Celular , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imino Açúcares/síntese química , Imino Açúcares/química , Simulação de Acoplamento Molecular , Estrutura Molecular , Mutação , Pirrolidinas/química , Relação Estrutura-Atividade , Propriedades de Superfície , Triazóis/químicaRESUMO
Inhibition of the biosynthesis of complex N-glycans in the Golgi apparatus is one of alternative ways to suppress growth of tumor tissue. Eight N-benzyl substituted 1,4-imino-l-lyxitols with basic functional groups (amine, amidine, guanidine), hydroxyl and fluoro groups were prepared, optimized their syntheses and tested for their ability to inhibit several α-mannosides from the GH family 38 (GMIIb, LManII and JBMan) as models for human Golgi and lysosomal α-mannoside II. All compounds were found to be selective inhibitors of GMIIb. The most potent structure bearing guanidine group, inhibited GMIIb at the micromolar level (Kiâ¯=â¯19⯱â¯2⯵M) while no significant inhibition (>2â¯mM) of LManII and JBMan was observed. Based on molecular docking and pKa calculations this structure may form two salt bridges with aspartate dyad of the target enzyme improving its inhibitory potency compared with other N-benzyl substituted derivatives published in this and previous studies.
Assuntos
Inibidores Enzimáticos/química , Imino Açúcares/química , Álcoois Açúcares/química , alfa-Manosidase/antagonistas & inibidores , Animais , Domínio Catalítico , Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimologia , Ensaios Enzimáticos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/metabolismo , Imino Açúcares/síntese química , Imino Açúcares/metabolismo , Simulação de Acoplamento Molecular , Ligação Proteica , Álcoois Açúcares/síntese química , Álcoois Açúcares/metabolismo , alfa-Manosidase/química , alfa-Manosidase/metabolismoRESUMO
Synthetic analogues of the naturally occurring iminosugar homoDMDP, which feature a perfluoroalkyl group at the pseudo-anomeric position, have been synthesized from the corresponding sugar-derived cyclic aldonitrone. The new fluorinated iminosugars as well as homoDMDP and its 6-deoxy counterpart were evaluated for their inhibitory activity against a panel of glycosidases. While the replacement of the (1',2')-dihydroxyethyl substituent of homoDMDP with -C4F9 proved detrimental for enzyme binding, introduction of a -C3F7 moiety tuned the inhibitory activity spectrum selectively towards α-fucosidase and α-glucosidase from yeast.
Assuntos
Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Imino Açúcares/síntese química , Imino Açúcares/farmacologia , Alquilação , Aspergillus/enzimologia , Técnicas de Química Sintética , Inibidores Enzimáticos/química , Imino Açúcares/química , Estereoisomerismo , Relação Estrutura-AtividadeRESUMO
It is important to find more effective and safer immunosuppressants, because clinically used immunosuppressive agents have significant side effects. A series of N-substituted iminosugar derivatives were designed and synthesized, and their immunosuppressive effects were evaluated by the CCK-8 assay. The results revealed that iminosugars 10 e and 10 i, that is, (3R,4S)-1-(4-heptyloxylphenylethyl)pyrrolidine-3,4-diol and (3R,4S)-1-[2-(2-chloro-4-(p-tolylthio)-phenyl-1-yl)ethyl]pyrrolidine-3,4-diol, respectively, exhibited the strongest inhibitory effects on mouse splenocyte proliferation (IC50 =2.16 and 2.48⠵m, respectively), whereas the iminosugars containing an amide group near the hydrophilic head (compounds 10 j-n) exhibited no inhibitory effects. Further studies revealed that the inhibitory effects on splenocyte proliferation may have come from the suppression of both IFN-γ and IL-4 cytokines. Our results suggest that synthetic iminosugars, especially compounds 10 e and 10 i, hold potential as immunosuppressive agents.