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1.
Clin Pharmacokinet ; 62(8): 1093-1103, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37284974

RESUMO

BACKGROUND: Janagliflozin is a novel sodium-glucose cotransport-2 inhibitor. Despite its remarkable effect in glycemic control, no systematic research has evaluated the effect of renal impairment (RI) on its pharmacokinetics and pharmacodynamics. METHODS: Here, patients with T2DM (n = 30) were divided into normal renal function (eGFR ≥ 90 mL/min/1.73 m2), mild RI (eGFR between 60 and 89 mL/min/1.73 m2), moderate RI-I (eGFR between 45 and 59 mL/min/1.73 m2), and moderate RI-II (eGFR between 30 and 44 mL/min/1.73 m2) groups. They were administered 50 mg janagliflozin orally, and plasma and urine samples were collected for the determination of janagliflozin concentration. RESULTS: Following oral administration, janagliflozin was rapidly absorbed, with the time to Cmax of 2-6 h for janagliflozin and 3-6 h for its metabolite XZP-5185. Plasma exposure levels were similar for janagliflozin in T2DM patients with or without RI but decreased for the metabolite XZP-5185 in T2DM patients with eGFR between 45 and 89 mL/min/1.73 m2. Janagliflozin significantly promoted the excretion of urinary glucose, even in patients with reduced eGFR. Janagliflozin was well tolerated in patients with T2DM with or without RI, and no serious adverse events (SAEs) occurred during this trial. CONCLUSIONS: The exposure levels of janagliflozin in T2DM patients were slightly increased with worsening of RI (i.e., 11% increase in the AUC in patients with moderate RI compared with the normal renal function group). Despite worsening of renal function, janagliflozin exerted a significant pharmacologic effect and was well tolerated, even in patients with moderate RI, implying a promising role in the treatment of patients with in T2DM. REGISTRATION: China Drug Trial register ( http://www.chinadrugtrials.org.cn/I ) identifier no.: CTR20192721.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Renal , Xilitol , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , População do Leste Asiático , Glucose/metabolismo , Insuficiência Renal/complicações , Xilitol/análogos & derivados , Xilitol/farmacocinética
2.
Molecules ; 27(4)2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35209024

RESUMO

The synthesis of ß-galactosyl xylitol derivatives using immobilized LacA ß-galactosidase from Lactobacillus plantarum WCFS1 is presented. These compounds have the potential to replace traditional sugars by their properties as sweetener and taking the advantages of a low digestibility. The enzyme was immobilized on different supports, obtaining immobilized preparations with different activity and stability. The immobilization on agarose-IDA-Zn-CHO in the presence of galactose allowed for the conserving of 78% of the offered activity. This preparation was 3.8 times more stable than soluble. Since the enzyme has polyhistidine tags, this support allowed the immobilization, purification and stabilization in one step. The immobilized preparation was used in synthesis obtaining two main products and a total of around 68 g/L of ß-galactosyl xylitol derivatives and improving the synthesis/hydrolysis ratio by around 30% compared to that of the soluble enzyme. The catalyst was recycled 10 times, preserving an activity higher than 50%. The in vitro intestinal digestibility of the main ß-galactosyl xylitol derivatives was lower than that of lactose, being around 6 and 15% for the galacto-xylitol derivatives compared to 55% of lactose after 120 min of digestion. The optimal amount immobilized constitutes a very useful tool to synthetize ß-galactosyl xylitol derivatives since it can be used as a catalyst with high yield and being recycled for at least 10 more cycles.


Assuntos
Proteínas de Bactérias/química , Lactobacillus plantarum/enzimologia , Xilitol , beta-Galactosidase/química , Catálise , Xilitol/análogos & derivados , Xilitol/química
3.
Carbohydr Res ; 492: 107988, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32387805

RESUMO

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/química
4.
Molecules ; 21(10)2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27735872

RESUMO

A series of novel xylitan derivatives derived from xylitol were synthesized using operationally simple procedures. A xylitan acetonide was the key intermediate used to prepare benzoate, arylsulfonate esters and 1,2,3-triazole derivatives of xylitan. These compounds were evaluated for their in vitro anti-Trypanosoma cruzi activity against trypomastigote and amastigote forms of the parasite in T. cruzi-infected cell lineages. Benznidazole was used as positive control against T. cruzi and cytotoxicity was determined in mammalian L929 cells. The arylsulfonate xylitan derivative bearing a nitro group displayed the best activity of all the compounds tested, and was slightly more potent than the reference drug benznidazole. The importance of the isopropylidene ketal moiety was established and the greater lipophilicity of these compounds suggests enhancement in cell penetration.


Assuntos
Tripanossomicidas/síntese química , Tripanossomicidas/farmacologia , Xilitol/síntese química , Xilitol/farmacologia , Humanos , Testes de Sensibilidade Parasitária , Trypanosoma cruzi/efeitos dos fármacos , Xilitol/análogos & derivados
6.
J Asian Nat Prod Res ; 16(9): 930-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25253092

RESUMO

Two new compounds, xylitol 1-O-(6'-O-p-hydroxylbenzoyl)-glucopyranoside (1) and bambulignan B (2), together with three known ones gastrodin (3), glucovanillin (4), and rel-(7S,7'R,8R,8'S)-4,4'-dihydroxy-3,3',5,5'-tetramethoxy-7,7'-epoxyligna-9,9'-diol-9(or)9'-O-ß-glucopyranoside (5), were isolated from the 95% EtOH extract of the dry leaves of Pleioblastus amarus (Keng) keng f. Their structures were determined by UV, IR, HR-ESI-MS, CD, and 1D and 2D NMR data analyses as well as GC experiments.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Glucosídeos/isolamento & purificação , Lignanas/isolamento & purificação , Poaceae/química , Xilitol/análogos & derivados , Xilitol/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Glucosídeos/química , Lignanas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Xilitol/química
7.
Org Biomol Chem ; 12(23): 3932-43, 2014 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-24802185

RESUMO

The enantiomers of XYLNAc (2-N-acetylamino-1,2,4-trideoxy-1,4-iminoxylitol) are prepared from the enantiomers of glucuronolactone; the synthesis of the enantiomers of LYXNAc (2-N-acetylamino-1,2,4-trideoxy-1,4-iminolyxitol) from an L-arabinono-δ-lactone and a D-ribono-δ-lactone is reported. A comparison is made of the inhibition of ß-N-acetylhexosaminidases (HexNAcases) and α-N-acetylgalactosaminidase (α-GalNAcase) by 8 stereoisomeric 2-N-acetylamino-1,2,4-trideoxy-1,4-iminopentitols; their N-benzyl derivatives are better inhibitors than the parent compounds. Both XYLNAc and LABNAc are potent inhibitors against HexNAcases. None of the compounds show any inhibition of α-GalNAcase.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Iminas/química , Iminas/farmacologia , Xilitol/análogos & derivados , Xilitol/síntese química , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , Fabaceae/enzimologia , Pirrolidinas/química , Estereoisomerismo , Xilitol/química , beta-N-Acetil-Hexosaminidases/metabolismo
8.
Org Lett ; 15(21): 5610-2, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24125121

RESUMO

3-(Hydroxymethyl)xylitol, a compound reportedly isolated from the root of Casearia esculenta (Roxb.), along with its three possible stereoisomers, has been synthesized for the first time by way of a triple dihydroxylation reaction performed upon the simplest cross-conjugated hydrocarbon, [3]dendralene. The data for the natural product do not match any of the isomeric 3-(hydroxymethyl)pentitols. The structure of the natural product from the root of Casearia esculenta (Roxb.) has been corrected by reanalysis of the published data.


Assuntos
Casearia/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/química , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacologia , Fígado/química , Fígado/efeitos dos fármacos , Extratos Vegetais/análise , Extratos Vegetais/química , Raízes de Plantas/química , Xilitol/análogos & derivados , Animais , Produtos Biológicos , Hipoglicemiantes/isolamento & purificação , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Ratos , Estereoisomerismo , Xilitol/síntese química , Xilitol/química , Xilitol/isolamento & purificação , Xilitol/farmacologia
9.
Biomed Mater ; 8(3): 035006, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23558205

RESUMO

In order to develop degradable elastomers with a satisfactory combination of flexibility and enzyme-mediated degradation rate, the mechanical properties, enzymatic degradation kinetics and biocompatibility of poly(xylitol sebcate) (PXS) has been systematically investigated in comparison with poly(glycerol sebacate) (PGS). Under the same level of crosslinked density, the PXS elastomer networks have approximately twice the stretchability (elongation at break) of their PGS counterparts. This observation is attributable to the relatively longer and more orientable xylitol monomers, compared with glycerol molecules. Although xylitol monomers have two more hydroxyl groups, we, surprisingly, found that the hydrophilic side chains did not accelerate the water attack on the ester bonds of the PXS network, compared with their PGS counterpart. This observation was attributed to a steric hindrance effect, i.e. the large-sized hydroxyl groups can shield ester bonds from the attack of water molecules. In conclusion, the use of polyols of more than three -OH groups is an effective approach enhancing flexibility, whilst maintaining the degradation rate of polyester elastomers. Further development could be seen in the copolymerization of PPS with appropriate thermoplastic polyesters, such as poly(lactic acid) and polyhydroxyalkanoate.


Assuntos
Materiais Biocompatíveis/química , Decanoatos/química , Glicerol/análogos & derivados , Polímeros/química , Xilitol/análogos & derivados , Animais , Fenômenos Biomecânicos , Linhagem Celular , Proliferação de Células , Elastômeros/química , Esterificação , Fibroblastos/citologia , Glicerol/química , Teste de Materiais , Camundongos , Xilitol/química
10.
J Med Chem ; 55(6): 2737-45, 2012 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-22360565

RESUMO

A highly divergent route to lipophilic iminosugars that utilizes the thiol-ene reaction was developed to enable the rapid synthesis of a collection of 16 dideoxyiminoxylitols bearing various different lipophilic substituents. Enzyme kinetic analyses revealed that a number of these products are potent, low-nanomolar inhibitors of human glucocerebrosidase that stabilize the enzyme to thermal denaturation by up to 20 K. Cell based assays conducted on Gaucher disease patient derived fibroblasts demonstrated that administration of the compounds can increase lysosomal glucocerebrosidase activity levels by therapeutically relevant amounts, as much as 3.2-fold in cells homozygous for the p.N370S mutation and 1.4-fold in cells homozygous for the p.L444P mutation. Several compounds elicited this increase in enzyme activity over a relatively wide dosage range. The data assembled here illustrate how the lipophilic moiety common to many glucocerebrosidase inhibitors might be used to optimize a lead compound's ability to chaperone the protein in cellulo. The flexibility of this synthetic strategy makes it an attractive approach to the rapid optimization of glycosidase inhibitor potency and pharmacokinetic behavior.


Assuntos
Alilamina/análogos & derivados , Alilamina/síntese química , Carboidratos/síntese química , Doença de Gaucher/tratamento farmacológico , Glucosilceramidase/antagonistas & inibidores , Iminas/síntese química , Xilitol/análogos & derivados , Xilitol/síntese química , Alilamina/farmacologia , Carboidratos/farmacologia , Ensaios Enzimáticos , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Fibroblastos/patologia , Doença de Gaucher/enzimologia , Doença de Gaucher/patologia , Glucosilceramidase/genética , Humanos , Iminas/farmacologia , Isomerismo , Lisossomos/efeitos dos fármacos , Lisossomos/enzimologia , Mutação , Bibliotecas de Moléculas Pequenas , Relação Estrutura-Atividade , Xilitol/farmacologia
11.
J Asian Nat Prod Res ; 13(8): 700-6, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21751837

RESUMO

Casearia esculenta root (Roxb.) is widely used in traditional system of medicine to treat diabetes in India. An active compound, 3-hydroxymethyl xylitol (3-HMX), has been isolated, and its optimum dose has been determined in a short duration study and patented. In addition, the long-term effect of 3-HMX in type 2 diabetic rats on antihyperglycemic, antioxidants, antihyperlipidemic, and protein metabolism and kidney marker enzymes was investigated, and its effect was shown previously. In this study, we investigated the effect of 3-HMX on plasma and tissue glycoproteins in streptozotocin-diabetic rats. Animals were divided into five groups viz., control group, 3-HMX (40 mg/kg of body weight) treated group, diabetic group, diabetic+3-HMX (40 mg/kg of body weight), and diabetic+glibenclamide (600 µg/kg of body weight). 3-HMX was administered orally at a dose of 40 mg/kg of body weight for 45 days. The study shows significant increases in the level of sialic acid except kidney and elevated levels of hexose, hexosamine, and fucose in the liver and kidney of diabetic rats, and the treatment with 3-HMX and glibenclamide showed reversal of these parameters toward normalcy. Thus, the study indicates that 3-HMX possesses a significant beneficial effect on glycoprotein components.


Assuntos
Casearia/química , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Estreptozocina/farmacologia , Xilitol/análogos & derivados , Administração Oral , Animais , Glicemia/análise , Diabetes Mellitus Experimental/tratamento farmacológico , Fibronectinas/biossíntese , Fibronectinas/efeitos dos fármacos , Glibureto/uso terapêutico , Glicoforinas/efeitos dos fármacos , Glicoforinas/metabolismo , Glicoproteínas/sangue , Hipoglicemiantes/química , Insulina/sangue , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Neuraminidase/efeitos dos fármacos , Neuraminidase/metabolismo , Raízes de Plantas/química , Ratos , Ratos Wistar , Xilitol/química , Xilitol/isolamento & purificação , Xilitol/farmacologia
12.
J Org Chem ; 76(7): 2001-9, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21375224

RESUMO

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.


Assuntos
Lactamas/química , Álcoois Açúcares/síntese química , Xilitol/análogos & derivados , Alquilação , Arabinose , Imino Furanoses/síntese química , Imino Furanoses/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Estereoisomerismo , Álcoois Açúcares/química , Xilitol/síntese química , Xilitol/química
13.
J Biochem Mol Toxicol ; 24(2): 95-101, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20146230

RESUMO

Casearia esculenta root (Roxb.) is widely used in traditional system of medicine to treat diabetes in India. An active compound, 3-hydroxymethyl xylitol (3-HMX), has been isolated, and its optimum dose has been determined in a short duration study and patented. In addition, the long-term effect of 3-HMX in type 2 diabetic rats on carbohydrate metabolism was investigated, and its antihyperglycemic effect was shown previously (Chandramohan et al., Eur J Pharmacol 2008;590:437-443). In this study we investigated the effect of 3-HMX on plasma and tissue lipid profiles in streptozotocin-induced diabetic rats. Diabetes was induced in adult male albino rats of the Wistar strain, weighing 180-200 g, by administration of streptozotocin (40 mg/kg of body weight) intraperitoneally. The normal and diabetic rats were treated with 3-HMX (40 mg/kg BW/day) for 45 days. The levels of total cholesterol, triglycerides, free fatty acids, and phospholipids were assayed in the plasma besides lipoprotein-cholesterol (high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), and very low density lipoprotein-cholesterol (VLDL-C)) and tissues (liver, kidney, heart, and brain). Total cholesterol, triglyceride, free fatty acid, and phospholipid (LDL-C and VLDL-C in plasma only) levels increased in plasma and tissues significantly, whereas plasma HDL-C significantly decreased in diabetic rats. Treatment with 3-HMX or glibenclamide reversed the above-mentioned changes and improved toward normalcy. Histological study of liver also confirmed the biochemical findings. Thus administration of 3-HMX is able to reduce hyperglycemia and hyperlipidemia related to the risk of diabetes mellitus.


Assuntos
Casearia/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/uso terapêutico , Hipolipemiantes/uso terapêutico , Raízes de Plantas/química , Xilitol/análogos & derivados , Animais , Colesterol/sangue , Diabetes Mellitus Experimental/sangue , Ácidos Graxos não Esterificados/sangue , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Fosfolipídeos/sangue , Fitoterapia , Ratos , Ratos Wistar , Estreptozocina , Triglicerídeos/sangue , Xilitol/química , Xilitol/farmacologia , Xilitol/uso terapêutico
14.
J Org Chem ; 74(7): 2858-61, 2009 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-19278232

RESUMO

A highly regioselective reductive cleavage of the bis-benzylidene acetal of D-mannitol was performed using a BF(3) x Et(2)O/Et(3)SiH reagent system. A chiral intermediate 6 thus obtained was efficiently utilized in the stereoselective synthesis of the anticancer agent OGT2378 (3) and glycosidase inhibitor derivative N-tosyl 1,4-dideoxy-1,4-imino-L-xylitol (22). Chemoselective reduction of azido epoxide 10 followed by regioselective intramolecular cyclization of amino epoxide 11 resulted in the exclusive formation of deoxyidonojirimycin derivative 12. By changing the order of deprotection, the chiral intermediate 6 was readily transformed to glycosidase inhibitor derivative 22.


Assuntos
Acetais/química , Antineoplásicos/síntese química , Compostos de Benzilideno/química , Inibidores Enzimáticos/síntese química , Glicosídeo Hidrolases/antagonistas & inibidores , Imino Açúcares/síntese química , Piperidinas/síntese química , Xilitol/análogos & derivados , Antineoplásicos/química , Inibidores Enzimáticos/química , Glicosídeo Hidrolases/metabolismo , Imino Furanoses/síntese química , Imino Furanoses/química , Imino Açúcares/química , Manitol/química , Modelos Moleculares , Estrutura Molecular , Piperidinas/química , Estereoisomerismo , Xilitol/síntese química , Xilitol/química
15.
Eur J Pharmacol ; 590(1-3): 437-43, 2008 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-18635165

RESUMO

Casearia esculenta root (Roxb.) is widely used in traditional system of medicine to treat diabetes in India. An active compound 3-hydroxymethyl xylitol (3-HMX) has been isolated and its optimum dose has been determined in a short duration study and patented. In the present study, the long-term effect of 3-HMX in type 2 diabetic rats has been investigated. An optimum dose of 3-HMX (40 mg/kg body weight) was orally administered for 45 days to streptozotocin-diabetic rats for the assessment of glucose, insulin, hemoglobin (Hb), glycated hemoglobin (HbA(1c)), hepatic glycogen, and activities of carbohydrate metabolizing enzymes, such as glucokinase, glucose 6-phosphatase, fructose 1,6-bisphosphatase and glucose-6-phosphate dehydrogenase and hepatic marker enzymes, such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gammaglutamyl transferase (GGT) in normal and streptozotocin-diabetic rats. 3-HMX at 40 mg dose produced similar effects on all biochemical parameters studied as that of glibenclamide, a standard drug. Histological study of pancreas also confirmed the biochemical findings. These results indicate that 3-hydroxymethyl xylitol, the compound from C. esculenta, possesses antihyperglycemic effect on long-term treatment also.


Assuntos
Metabolismo dos Carboidratos/efeitos dos fármacos , Casearia/química , Diabetes Mellitus Experimental/metabolismo , Xilitol/análogos & derivados , Alanina Transaminase/sangue , Animais , Peso Corporal/efeitos dos fármacos , Hemoglobinas Glicadas/análise , Insulina/sangue , Fígado/metabolismo , Masculino , Pâncreas/patologia , Raízes de Plantas/química , Ratos , Estreptozocina , Xilitol/farmacologia
16.
J Nat Prod ; 70(3): 436-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17378534

RESUMO

The alpha-glucosidase inhibitor 1,4-dideoxy-1,4-imino-D-arabinitol (1) was isolated from two marine sponges collected in Western Australia and shown by LC-MS to be responsible for the alpha-glycosidase inhibitory activity in different sponge extracts collected over a wide geographic area. The configuration of 1 was determined by application of Marfey's method. The two most inhibitory extracts contained only 1, while the less inhibitory extracts contained 1,4-dideoxy-1,4-imino-D-xylitol (2) or the putative diastereomeric imino pentitols 3 and 4. The least active or inactive extracts showed no detectable imino pentitols. While both 1 and 2 are known from plants, this is the first report on the isolation and detection of 1 and 2 in marine invertebrates.


Assuntos
Inibidores de Glicosídeo Hidrolases , Poríferos/química , Álcoois Açúcares/isolamento & purificação , Álcoois Açúcares/farmacologia , Animais , Arabinose , Imino Furanoses , Estrutura Molecular , Álcoois Açúcares/química , Austrália Ocidental , Xilitol/análogos & derivados , Xilitol/química , Xilitol/isolamento & purificação , Xilitol/farmacologia , Leveduras/enzimologia
18.
Carbohydr Res ; 339(16): 2731-2, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15519332

RESUMO

1,5-Anhydroxylitol, a compound never found previously in the vegetal kingdom was obtained from Olea europaea leaves in approximately 0.5-1% yield.


Assuntos
Olea/química , Xilitol/análogos & derivados , Xilitol/isolamento & purificação , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química
19.
Carbohydr Res ; 339(13): 2177-85, 2004 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-15337445

RESUMO

6-O-(4,4,5,5,6,6,7,7,7-Nonafluoro-2-hydroxyheptyl)-, 6-O-(4,4,5,5,6,6,7,7,8,8,9,9,9-tridecafluoro-2-hydroxynonyl)-, and 6-O-(4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoro-2-hydroxyundecyl)-d-galactopyranose (9, 10, and 11, resp.) were prepared by a two-step synthesis including the reaction of 1,2:3,4-di-O-isopropylidene-alpha-d-galactopyranose with 2-[(perfluoroalkyl)methyl]oxiranes under catalysis with BF(3).Et(2)O. Similarly, 1-O-(4,4,5,5,6,6,7,7,7-nonafluoro-2-hydroxyheptyl)-, 1-O-(4,4,5,5,6,6,7,7,8,8,9,9,9-tridecafluoro-2-hydroxynonyl)-, 1-O-(4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoro-2-hydroxyundecyl)-dl-xylitol (18, 19, and 20, resp.) were prepared by a two-step synthesis from the corresponding 1,2:3,4-di-O-isopropylidene-dl-xylitol. Most of the both types of fluoroalkylated carbohydrate derivatives 9-11 and 18-20 generally displayed very low level of hemolytic activity and excellent co-emulsifying properties on testing on perfluorodecalin-Pluronic F-68 microemulsions.


Assuntos
Eritrócitos/fisiologia , Fluorocarbonos , Galactose/análogos & derivados , Galactose/química , Xilitol/análogos & derivados , Xilitol/química , Alcenos , Alquilação , Configuração de Carboidratos , Emulsões , Galactose/sangue , Galactose/síntese química , Humanos , Indicadores e Reagentes , Modelos Moleculares , Xilitol/sangue , Xilitol/síntese química
20.
J Am Chem Soc ; 126(39): 12458-69, 2004 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-15453780

RESUMO

The syntheses of N-alkylated deoxynojirimycin and 1,5-dideoxy-1,5-iminoxylitol derivatives having either a D- or an L-erythritol-3-sulfate functionalized N-substituent are reported. The alkylating agent used was a cyclic sulfate derivative, whereby selective attack of the nitrogen atom at the least hindered primary center afforded the desired ammonium salt. In aqueous solution, these salts were configurationally labile at the ammonium center. Sulfonium and/or selenonium analogues of the ammonium salts were prepared by analogous reactions. The chalcogen salts were obtained as mixtures of diastereomers, separable in some cases, differing only in the stereochemistry at the configurationally stable sulfur or selenium atoms. Proof of configuration and conformation of each compound was obtained by detailed NMR experiments. The compounds are six-membered ring analogues of salacinol, a known sulfonium-salt glucosidase inhibitor. Evaluation of the target compounds for enzyme inhibition of the glucosidase enzyme glucoamylase G2 indicated that these compounds were either inactive or, at best, only weak inhibitors of maltose hydrolysis.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Inibidores Enzimáticos/síntese química , Glicosídeo Hidrolases/antagonistas & inibidores , Compostos Organosselênicos/síntese química , Compostos de Sulfônio/síntese química , Xilitol/análogos & derivados , 1-Desoxinojirimicina/síntese química , 1-Desoxinojirimicina/farmacologia , Alquilação , Aspergillus niger/enzimologia , Sequência de Carboidratos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Glucana 1,4-alfa-Glucosidase/antagonistas & inibidores , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Compostos Organosselênicos/química , Compostos Organosselênicos/farmacologia , Relação Estrutura-Atividade , Compostos de Sulfônio/química , Compostos de Sulfônio/farmacologia , Xilitol/síntese química , Xilitol/farmacologia
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