- ACETONIDES OF α-HYDROXY-δ-ALTRONOLACTONES
-
The preparation and characterisation of some derivatives of α-hydroxy-δ-lactones, in which the δ-carbon substituent on the lactone ring is trans to an adjacent isopropylidene protected diol, are described; the X-ray crystal structures of 3,4-O-isopropylidene-D-altrono-1,5-lactone and of 3,4:6,7-di-O-isopropylidene-D-glycero-Daltro-heptono-1,5-lactone are reported.
- Bichard, Claire J. F.,Fairbanks, Antony J.,Fleet, George W. J.,Ramsden, Nigel G.,Vogt, Klaus,et al.
-
-
Read Online
- A facile ultrasound-assisted synthesis of methyl 2,3-O-isopropylidene-β-D-ribofuranoside from D-ribose and its use to prepare new 1,2,3-triazole glycoconjugates
-
The conversion of D-ribose into its 2,3-O-isopropylidene derivative using ultrasonic irradiation is described. The ultrasound proved to be an excellent alternative as the energy source for the reaction. Different reaction times were investigated, and shorter reaction times and high yield were achieved without the need for purification of the acetonide. The compound was then applied as the starting material in the synthesis of 23 new glycoconjugates of 1,2,3-triazole that are tethered together in different ways. The synthesized compounds were characterized by FTIR, 1H NMR, 13C NMR, and HRMS techniques.
- Evangelista, Tereza Cristina Santos,Aquino, Gabriel Alves Souto de,Donza, Marcio Roberto H.,Leit?o, Rafael Lisboa,Carvalho, Victor Salarolli de,Kaiser, Carlos Roland,Ferreira, Sabrina Baptista
-
p. 243 - 268
(2021/10/23)
-
- New glycosylated platinum(II) phthalocyanine containing ribose moiety – synthesis and photophysical properties
-
The synthesis and spectral characterisation of new glycoconjugated phthalonitrile connected with triazole linker via Cu(II)-mediated click reaction is reported. Treatment of azido derivative of 1-methoxy-2,3- O-isopropylidene-β-D-ribose with 4-O-propargyloxy-substituted phthalonitrile in presence copper(II) sulfate pentahydrate and sodium L-ascorbate in tert-butanol/water gave desired glycophthalonitrile with 84% yield. This precursor underwent mixed-cyclisation with the tert-butyl-substituted phthalonitrile, to afford the mono-glycosylated A3B-type platinum(II) phthalocyanine. Upon irradiation this compound could sensitise the formation of singlet oxygen in acetone, with 0.95 quantum yield by comparative method with use of 1,3-diphenylisobenzofuran (DPBF) as scavenger.
- Burtsev, Ivan D.,Volov, Alexander N.
-
-
- Synthesis and antimicrobial evaluation of amino sugar-based naphthoquinones and isoquinoline-5,8-diones and their halogenated compounds
-
Antibiotic resistance has emerged as a serious global public health problem and lately very few antibiotics have been discovered and introduced into clinical practice. Therefore, there is an urgent need for the development of antibacterial compounds with new mechanism of action, especially those capable of evading known resistance mechanisms. In this work two series of glycoconjugate and non-glycoconjugate amino compounds derived from of isoquinoline-5,8-dione and 1,4-naphthoquinone and their halogenated derivatives were synthesized and evaluated for antimicrobial activity against Gram-positive (Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, S. epidermidis ATCC 12228, S. simulans ATCC 27851) and Gram-negative bacteria (E. coli ATCC 25922, Proteus mirabilis ATCC 15290, K. pneumoniae ATCC 4352 and P. aeruginosa ATCC 27853) strains of clinical importance. This study revealed that glycoconjugate compounds derived from halogeno-substituted naphthoquinones were more active against Gram-negative strains, which cause infections whose treatment is even more difficult, according to the literature. These molecules were also more active than isoquinoline-5,8-dione analogues with minimum inhibitory concentration (MIC = 4–32 μg/mL) within Clinical and Laboratory Standard Institute MIC values (CLSI 0.08–256 μg/mL). Interestingly the minimal bactericidal concentration (MBC) values of the most active compounds were equal to MIC classifying them as bactericidal agents against Gram-negative bacteria. Sixteen compounds among eighteen carbohydrate-based naphthoquinones tested showed no hemolytic effects on health human erythrocytes whereas more susceptibility to hemolytic cleavage was observed when using non-glycoconjugate amino compounds. In silico Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) evaluation also pointed out that these compounds are potential for oral administration with low side effects. In general, this study indicated that these compounds should be exploited in the search for a leading substance in a project aimed at obtaining new antimicrobials more effective against Gram-negative bacteria.
- Dias, Flaviana R.F.,Novais, Juliana S.,Devillart, Talita A. do Nascimento Santos,da Silva, Wanderson Amaral,Ferreira, Matheus O.,Loureiro, Raquel de S.,Campos, Vinícius R.,Ferreira, Vitor F.,de Souza, Maria C.B.V.,Castro, Helena C.,Cunha, Anna C.
-
-
- Synthesis of a new class of naphthoquinone glycoconjugates and evaluation of their potential as antitumoral agents
-
A novel series of carbohydrate-based naphthoquinones was synthesized and evaluated for cytotoxicity against different cancer cell lines. The compounds derived from 5-hydroxy-1,4-naphthoquinone (juglone) showed better cytotoxicity profiles against HCT-116, A-549 and MDA-MB 435 human cancer cells than the parent compound. The results suggest that the hydroxyl group on the aromatic ring increased the pro-oxidant activity of these new naphthoquinone derivatives. Furthermore, two derivatives were found to be more active against melanoma cells (MDA-MB435) than the clinically useful anticancer agent doxorubicin, and none of the compounds caused mouse erythrocyte lysis.
- Campos, Vinicius R.,Cunha, Anna C.,Silva, Wanderson A.,Ferreira, Vitor F.,Santos De Sousa, Carla,Fernandes, Patrícia D.,Moreira, Vinícius N.,Da Rocha, David R.,Dias, Flaviana R. F.,Montenegro, Raquel C.,De Souza, Maria C. B. V.,Boechat, Fernanda Da C. S.,Franco, Caroline F. J.,Resende, Jackson A. L. C.
-
p. 96222 - 96229
(2015/11/24)
-
- Click chemistry inspired highly facile synthesis of triazolyl ethisterone glycoconjugates
-
Numerous deoxy-azido sugars 3 were prepared by the reaction of tosyl/bromo sugars with NaN3 in dry DMF under heating condition. The 1,3-dipolar cycloaddition of deoxy-azido sugars 3 with ethisterone 4 to afford regioselective triazole-linked ethisterone glycoconjugates 5 was investigated in the presence of CuI and DIPEA in dichloromethane or CuSO4· 5H2O and sodium ascorbate in aqueous medium. All the developed compounds were characterized by spectroscopic analysis (IR, 1H & 13C NMR, and MS spectra). Structure of triazolyl ethisterone glycoconjugate 5a has been further confirmed by its Single Crystal X-ray analysis.
- Kumar, Dhananjay,Mishra, Kunj B.,Mishra, Bhuwan B.,Mondal, Saheli,Tiwari, Vinod K.
-
supporting information
p. 71 - 79
(2014/01/17)
-
- Structure-activity relationship of adenosine 5′-diphosphoribose at the transient receptor potential melastatin 2 (TRPM2) channel: Rational design of antagonists
-
Adenosine 5′-diphosphoribose (ADPR) activates TRPM2, a Ca 2+, Na+, and K+ permeable cation channel. Activation is induced by ADPR binding to the cytosolic C-terminal NudT9-homology domain. To generate the first structure-activity relationship, systematically modified ADPR analogues were designed, synthesized, and evaluated as antagonists using patch-clamp experiments in HEK293 cells overexpressing human TRPM2. Compounds with a purine C8 substituent show antagonist activity, and an 8-phenyl substitution (8-Ph-ADPR, 5) is very effective. Modification of the terminal ribose results in a weak antagonist, whereas its removal abolishes activity. An antagonist based upon a hybrid structure, 8-phenyl-2′-deoxy-ADPR (86, IC50 = 3 μM), is more potent than 8-Ph-ADPR (5). Initial bioisosteric replacement of the pyrophosphate linkage abolishes activity, but replacement of the pyrophosphate and the terminal ribose by a sulfamate-based group leads to a weak antagonist, a lead to more drug-like analogues. 8-Ph-ADPR (5) inhibits Ca2+ signalling and chemotaxis in human neutrophils, illustrating the potential for pharmacological intervention at TRPM2.
- Moreau, Christelle,Kirchberger, Tanja,Swarbrick, Joanna M.,Bartlett, Stephen J.,Fliegert, Ralf,Yorgan, Timur,Bauche, Andreas,Harneit, Angelika,Guse, Andreas H.,Potter, Barry V. L.
-
p. 10079 - 10102
(2014/01/17)
-
- Reactions of several monosaccharide-derived alcohols with p-acetamidobenzenesulfonyl azide and DBU
-
Attempted diazo transfer to 1-O-(2-phenylacetyl)-2,3;5,6-di-O- isopropylidene-α-d-mannofuranose using p-acetamidobenzenesulfonyl azide (p-ABSA) and DBU as base affords 1-O-(2-diazo-2-phenylacetyl)-2,3;5,6-di-O- isopropylidene-α-d-mannofuranose in low yield along with 2,3;5,6-di-O-isopropylidene-α-d-mannofuranose, 1-azido-2,3;5,6-di-O- isopropylidene-β-d-mannofuranose, as well as the unreacted starting material. The azido sugar likely arises from α-mannofuranosyl sulfonate ester formation, through displacement of azide from p-ABSA by the sugar lactol, followed by stereospecific displacement by azide anion on the furanosyl sulfonate ester. This outcome has been studied further with the conditions being applied to several common monosaccharide derivatives. Accessible substrates afford the azido sugar in an overall one-pot alcohol-to-azide conversion, while hindered substrates yield the sulfonate esters.
- Sacui, Iulia A.,Norris, Peter
-
supporting information; experimental part
p. 2670 - 2672
(2011/06/10)
-
- Synthesis, Biological Activity, and Molecular Modeling Studies of 1H-1,2,3-Triazole Derivatives of Carbohydrates as a-Glucosidases Inhibitors
-
A class of drugs in use for treating type II diabetes mellitus (T2D), typified by the pseudotetrasaccharide acarbose, act by inhibiting the a-glucosidase activity present in pancreatic secretions and in the brush border of the small intestine. Herein, we report the synthesis of a series of 4-substituted 1,2,3-triazoles conjugated with sugars, including D-xylose, D-galactose, D-allose, and D-ribose. Compounds were screened for a-glucosidase inhibitory activity using yeast maltase (MAL12) as a model enzyme. Methyl2,3-O-isopropylidene-β-D-ribofuranosides, such as the 4-(l-cyclohexenyl)-l,2,3-triazole derivative, were among the most active compounds, showing up to 25-fold higher inhibitory potency than the complex oligosaccharide acarbose. Docking studies on a MAL12 homology model disclosed a binding mode consistent with a transition-state-mimicking mechanism. Finally, the actual pharmacological potential of this triazole series was demonstrated by the reduction of postprandial blood glucose levels in normal rats. These compounds could represent new chemical scaffolds for developing novel drugs against T2D.
- Ferreira, Sabrinab,Sodero, Ana C. R.,Cardoso, Mariana F. C.,Lima, Emerson S.,Kaiser, Carlos R.,Silva Jr., Floriano P.,Ferreira, Vitor F.
-
supporting information; experimental part
p. 2364 - 2375
(2010/09/04)
-
- Chemical investigations in the synthesis of O-serinyl aminoribosides
-
Glycosylation involving d-ribose derivatives and various N-protected tert-butyl l-serinates can be achieved efficiently by careful choice of the activation method at the anomeric position and of the Lewis acid promoter. The conditions described allow the major formation of the β-anomer required for further elaboration to liposidomycin and caprazamycin analogues.
- Ginisty, Maryon,Gravier-Pelletier, Christine,Le Merrer, Yves
-
p. 142 - 150
(2007/10/03)
-
- Studies on the synthesis of tunicamycin. The preparation of 7-deoxy-2-deamino-6-hydroxy tunicamine and related products
-
The condensation of methyl 5-deoxy-5-diazo-2,3-O-isopropylidene-β-D-ribofuranoside with 1,2:3,4-di-O-isopropylidene-D-galactohexonodialdo-1,5-pyranoside gave the ketone C-disaccharide 11 as the sole product. This ketone was transformed into different derivatives. Thus, its reduction led stereoselectively to the corresponding alcohols. Similar transformations led to the corresponding alkane and amino derivatives, of potential biological interest as inhibitors for glycosidases. These results can be useful for the synthesis of tunicamine and its analogues.
- Sarabia-Garcia, Francisco,Lopez-Herrera, F. Jorge
-
p. 4757 - 4768
(2007/10/03)
-
- Synthesis of 5'-fluoro-5'-deoxy- and 5'-amino-5'-deoxytoyocamycin and sangivamycin and some related derivatives
-
A series of 5'-substituted analogs of toyocamycin were prepared by condensation of silylated 4-amino-6-bromo-5-cyanopyrrolo[2,3-d]pyrimidine with protected 5-azido-5-deoxy- or 5-fluoro-5-deoxyribofuranose followed by debromination and deblocking. Alternatively, 5'-azido-5'-deoxytoyocamycin was prepared by azidation of toyocamycin. Conversion of the 5-nitrile function of the toyocamycin derivatives into a carboxamide or a thiocarboxamide gave the corresponding analogs of sangivamycin or thiosangivamycin while reduction of the 5'-azido-5'-deoxy nucleosides provided 5'-amino-5'-deoxy derivatives.
- Sharma,Li,Ledvina,Bobek
-
p. 1831 - 1852
(2007/10/02)
-
- HYDROGEN AZIDE-AMINE SYSTEMS AS AN AZIDE NUCLEOPHILE FOR SUBSTITUTIONS OF SULFONATES, HALIDES, AND VICINAL DISULFONATES
-
Hydrogen azide-alkylamine combination turned out to ensure the displacement of simple primary or secondary sulfonates, halides, and vicinal disulfonates with an azido-group in which an enhanced reactivity is generally achieved as compared with a case of traditional alkali metal azides.
- Saito, Seiki,Yokoyama, Hajime,Ishikawa, Teruhiko,Niwa, Nobuko,Morikawe, Toshio
-
p. 663 - 666
(2007/10/02)
-