Preparation of 5-Benzyluracil and 5-Benzylcytosine Nucleosides as Potential Inhibitors of Uridine Phosphorylase

1996 ◽  
Vol 61 (4) ◽  
pp. 627-644 ◽  
Author(s):  
Marcela Krečmerová ◽  
Hubert Hřebabecký ◽  
Antonín Holý
Keyword(s):  
Methyl Iodide ◽  
Thionyl Chloride ◽  
Alkaline Hydrolysis ◽  
Room Temperature ◽  
Silver Oxide ◽  
Uridine Phosphorylase ◽  
Cyclic Sulfite ◽  
Potential Inhibitors ◽  
Hydrolysis Of ◽  
Tin Tetrachloride

Reaction of 3,4,6-tri-O-acetyl-2-deoxyglucopyranosyl bromide (1) with silylated 5-benzyluracil and subsequent ammonolysis afforded α- and β-anomers of 5-benzyl-1-(2-deoxy-D-glucopyranosyl)uracil (2 and 3). Under catalysis with tin tetrachloride, silylated 5-benzyluracil reacted with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose to give 2',3',5'-tri-O-benzoyl-5-benzyluridine (10), which was converted into the 4-thio derivative 11 by reaction with Lawesson reagent. Debenzoylation of compound 11 afforded 5-benzyl-4-thiouridine (12), whereas its reaction with methyl iodide and deblocking gave 4-methylthiopyrimidine nucleoside 14. Amonolysis of derivative 12 at elevated temperature afforded 5-benzylcytidine (15). This reacted with thionyl chloride at room temperature to give cyclic sulfite 16 which on heating at 100 °C in dimethylformamide was converted into 5-benzyl-2,2'-cyclocytidine (17). Mild alkaline hydrolysis of compound 17 afforded 1-(β-D-arabinofuranosyl)-5-benzylcytosine (18). With boiling thionyl chloride, compound 15 formed 2',3'-cyclic sulfite 19 which on alkaline hydrolysis gave 5-benzyl-5'-chloro-5'-deoxycytidine (20). Compound 20 was reduced with tributylstannane to 5-benzyl-5'-deoxycytidine (21). Reaction of silylated 5-benzyluracil with 2-deoxy-3,5-bis(O-p-toluoyl)-D-ribofuranosyl chloride, catalyzed with mercury(II) bromide, afforded 5-benzyl-2'-deoxy-3',5'-bis(O-p-toluoyl)uridine (22) and its α-anomer 23. With Lawesson reagent, compound 22 gave 5-benzyl-4-thiouracil derivative 24 which was ammonolyzed to give 5-benzyl-2'-deoxycytidine (25). Analogously, compound 23 was converted into 5-benzyl-2-deoxy-α-cytidine (27). 5'-O-Benzoyl-5-benzyluridine (29) was converted into the 2,2'-anhydro derivative 30 which on reaction with hydrogen chloride afforded 3'-chloro-3'-deoxynucleoside 31. This compound was reduced with tributylstannane and the obtained 2'-deoxynucleoside 32 on treatment with thionyl chloride gave a mixture of erythro- and threo-3'-chloro-2',3'-dideoxynucleosides (33 and 34, respectively) which were reduced to 5'-O-benzoyl-5-benzyl-2',3'-dideoxyuridine (35). Compound 35 reacted with Lawesson reagent under formation of 4-thiouracil derivative 36 and this was deblocked to 5-benzyl-4-thio-2',3'-dideoxyuridine (37). On heating with ammonia, compound 37 was converted into 5-benzyl-2',3'-dideoxycytidine (38). Reaction of 4-thiouracil derivative with methyl iodide and subsequent hydrazinolysis afforded 4-hydrazino derivative 40 which was heated with silver oxide in ethanol to give a mixture of anomeric 5-benzyl-1-(2,3-dideoxyribofuranosyl)-2(1H)-pyrimidinones (42).

Synthesis of 5-Phenylcytosine Nucleoside Derivatives

1996 ◽  
Vol 61 (4) ◽  
pp. 645-655 ◽  
Author(s):  
Marcela Krečmerová ◽  
Hubert Hřebabecký ◽  
Antonín Holý
Keyword(s):  
Acetic Anhydride ◽  
Thionyl Chloride ◽  
Alkaline Hydrolysis ◽  
Hydrogen Bromide ◽  
Analogous Reaction ◽  
Final Reaction Product ◽  
Cyclic Sulfite ◽  
Higher Temperature ◽  
Hydrolysis Of ◽  
Tin Tetrachloride

Reaction of silylated 5-phenylcytosine with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribose, catalyzed with tin tetrachloride, and subsequent methanolysis afforded 5-phenylcytidine (2). This compound reacted with thionyl chloride in acetonitrile to give cyclic sulfite 3 which on heating in dimethylformamide was converted into 2,2'-anhydro-1-(β-D-arabinofuranosyl)-5-phenylcytosine (4). Analogous reaction of compound 2 with thionyl chloride at reflux gave 5'-chloro-5'-deoxy-2',3'-cyclic sulfite 5. Its heating in dimethylformamide afforded 5'-chloro-2,2'-anhydro derivative 6, mild alkaline hydrolysis led to 5'-chloro-5'-deoxy-5-phenylcytidine (7). Alkaline hydrolysis of 5-phenyl-2,2'-anhydrocytidine (4) gave 5-phenylcytosine arabinoside 8, whereas the 2,2'-anhydro derivative 6 afforded 1-(5-chloro-5-deoxy-β-D-arabinofuranosyl)-5-phenylcytosine (11). At higher temperature, the final reaction product was 2,5'-anhydro-5-phenylcytidine (12). 5'-Chloro-5'-deoxynucleosides 7 and 11 reacted with tri-n-butyl- stannane to give 5'-deoxyribofuranosyl and 5'-deoxyarabinofuranosyl derivatives 15 and 16. 5-Phenylcytidine (2) was converted into the N4-acetate 17 with acetic anhydride. Further reaction with acetic anhydride and hydrogen bromide in acetic acid afforded a mixture of peracetylated 2'-bromo and 3'-bromo derivatives 18 and 19. Reaction with Zn/Cu couple gave 5'-O-acetyl-5-phenyl-2',3'-didehydro derivative 20 and 2',3',5'-tri-O-acetyl-5-phenylcytidine (21). Compound 20 was deblocked to 1-(2,3-dideoxy-β-D-glycero-pent-2-enofuranosyl)-5-phenylcytosine (22). Catalytic hydrogenation of compound 20 over palladium and subsequent deblocking of the protected 2',3'-dideoxy derivative 23 gave 1-(2,3-dideoxy-β-D-glycero-pentofuranosyl)-5-phenylcytosine (24).

Preparation of 6-amino-6-deoxy-2,3,4,5-tetra-O-methyl-D-gluconic acid and its derivatives

1984 ◽  
Vol 49 (11) ◽  
pp. 2665-2673 ◽  
Author(s):  
Karel Kefurt ◽  
Zdeňka Kefurtová ◽  
Jiří Jarý
Keyword(s):  
Methyl Iodide ◽  
Alkaline Hydrolysis ◽  
Gluconic Acid ◽  
Silver Oxide ◽  
Catalytic Reduction ◽  
Hydrolysis Of

6-Amino-6-deoxy-2,3,4,5-tetra-O-methyl-D-gluconic acid (I) was prepared by catalytic reduction of 6-azido-6-deoxy-2,3,4,5-tetra -O-methyl-D-gluconic acid (XVI) obtained by alkaline hydrolysis of the corresponding dimethylamine VIII or a mixture of dimethylamide VIII, amide XIV and methylamide XV. Amides VIII, XIV and XV are the products of alkylation of 6-azido-6-deoxy-D-gluconamide (VII) or 6-azido-6-deoxy-3,5-di-O-methyl-D-gluconamide (XIII), carried out with methyl iodide and silver oxide in N,N-dimethylformamide. Amides VII and XIII were prepared by amonolysis of 6-azido-6-deoxy-D-glucono-1,5-lactone (III) or 6-azido-6-deoxy-3,5-di-O-methyl-D-glucono-1,4-lactone (XII). Methylation of 6-amino-6-deoxy-D-gluconolactam (II) with methyl iodide and silver oxide in N,N-dimethylformamide afforded 6-deoxy-2,3,4,5-tetra-O-methyl-6-methylamino-D-gluconolactam (V) from which 6-deoxy-2,3,4,5-tetra-O-methyl-6-methylamino-D-gluconic acid (VI) was prepared.

The Chemical Evolution of a Nitrogenase Model, 20 Alkyl Molybdates(VI) and the Mechanism of Hydrocarbon Production by Nitrogenase [1]

1982 ◽  
Vol 37 (3) ◽  
pp. 380-385 ◽  
Author(s):  
G. N. Schrauzer ◽  
Laura A. Hughes ◽  
Norman Strampach
Keyword(s):  
Aqueous Solution ◽  
Alkaline Hydrolysis ◽  
Room Temperature ◽  
Bond Cleavage ◽  
Model Compounds ◽  
Hydrocarbon Production ◽  
Acidic Solutions ◽  
Reducing Conditions ◽  
Hydrolysis Of ◽  
Derivatives Of

Abstract Colorless alkylmolybdates(VI) of composition R-MoO3-are generated in aqueous solutions by the alkaline hydrolysis of complexes R-Mo(Bpy)(0)2Br(Bpy = 2,2′-bipyridyl, R = CH3 and higher alkyl). At room temperature in alkaline aqueous solution, the new organometallic derivatives of oxomolybdate(VI) are remarkably resistant against Mo-C bond hydrolysis. Decomposition occurs more rapidly on heating, affording unrearranged alkanes according to the eq.: R-MoO3- + OH-→RH + Mo04=. In acidic solutions, the methylmolybdate(VI) species decomposes with the formation of a mixture of methane and ethane while higher alkylmolybdates carrying hydrogen in the β-position relative to molybdenum undergo Mo-C bond heterolysis by way of β-elimina-tion: R-CH2CH2-MoO3 → Mo+4 (aq) + H+ + R-CH = CH2. The Mo-C bond of alkylmolybdates is resistant to oxidants but is very sensitive to cleavage under reducing conditions. Reductive Mo-C bond cleavage occurs particularly rapidly in the presence of thiols and reduced ferredoxin model compounds. The latter reactions simulate the terminal steps of hydrocarbon producing reactions of nitrogenase with alternate substrates such as CN-, R-CN or R-NC, confirming previous mechanistic conclusions concerning the mechanism of nitrogenase action.

Quaternary salts of N,N-dimethylaminoethyl esters of pivalic and 2-methyl-3-methoxypropionic acid and their hydrolysis

1986 ◽  
Vol 51 (1) ◽  
pp. 206-214 ◽  
Author(s):  
Stanislav Ševčík ◽  
Martin Přádný
Keyword(s):  
Methyl Iodide ◽  
Alkaline Hydrolysis ◽  
Structural Unit ◽  
Model Compounds ◽  
Dimethylaminoethyl Methacrylate ◽  
Quaternary Salts ◽  
Terminal Unit ◽  
Kinetics Of ◽  
Hydrolysis Of

The synthesis and kinetics of quaternization of model compounds of poly(N,N-dimethylaminoethyl methacrylate) in water-alcoholic solutions brought about by methyl iodide and the alkaline hydrolysis of products in water have been investigated. N,N-Dimethylaminoethyl pivalate was selected as a model of the structural unit of the reported polymer; N,N-dimethylaminoethyl-2-methyl-3-methoxypropionate was the model of the terminal unit of the anionically prepared polymer.

Potential Nootropic Agents: Synthesis of Some 1,4-Disubstituted 2-Oxopyrrolidines and Some Related Compounds

1994 ◽  
Vol 59 (5) ◽  
pp. 1126-1136 ◽  
Author(s):  
Vladimír Valenta ◽  
Jiří Urban ◽  
Jan Taimr ◽  
Zdeněk Polívka
Keyword(s):  
Carboxylic Acid ◽  
Dicarboxylic Acid ◽  
Itaconic Acid ◽  
Thionyl Chloride ◽  
Alkaline Hydrolysis ◽  
Nootropic Activity ◽  
Carbonyl Chloride ◽  
Nootropic Agents ◽  
Hydrolysis Of ◽  
Related Compounds

4-(Aminomethyl)-1-benzyl-2-oxopyrrolidine (VI) was transformed by treatment with (4-benzhydrylpiperazin-1-yl)carbonyl chlorides IIIb - IIId and with (4-methylpiperazin-1-yl)carbonyl chloride (IIIa) to the carboxamides IVa - IVd. Heating of 1-(ethoxycarbonylmethyl)-2,4-dioxopyrrolidine (XIX) in acetonitrile in the presence of water afforded XVIIIa. Treatment with ammonia led to the diamide XVIIIc, while alkaline hydrolysis of XVIIIa gave the dicarboxylic acid XVIIIb. 4-(Aminomethyl)-1-(4-methylthiobenzyl)-2-oxopyrrolidine (XII) was prepared by the reaction of 4-(methylthio)benzylamine with itaconic acid and the following sequence of reactions starting from the obtained carboxylic acid VII including esterification, reduction and treatment the obtained alcohol IX with thionyl chloride, synthesis of phthalimido derivative XI and hydrazinolysis. Amine XII added to 4-chlorophenyl isocyanate formed XIII. The compounds prepared were tested for nootropic activity.

THE EFFECT ON REACTION RATES CAUSED BY THE SUBSTITUTION OF C14 FOR C12: I. THE ALKALINE HYDROLYSIS OF CARBOXYL-LABELED ETHYL BENZOATE

1949 ◽  
Vol 27b (10) ◽  
pp. 807-812 ◽  
Author(s):  
William H. Stevens ◽  
Richard W. Attree
Keyword(s):  
Alkaline Hydrolysis ◽  
Rate Constants ◽  
Room Temperature ◽  
Reaction Rates ◽  
Ethyl Benzoate ◽  
Hydrolysis Rate ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of

A study of the alkaline hydrolysis of C14 carboxyl-labeled ethyl benzoate has shown that the substitution of C14 for C12 changes the rate of hydrolysis of the ester. Ester molecules containing C14 hydrolyze at a slower rate than normal ester molecules. The ratio of the hydrolysis rate constants at room temperature has been found to be 0.86 ± 0.016.

Lattice imaging and pore structure of β ferric oxyhydroxide

1978 ◽  
Vol 36 (1) ◽  
pp. 264-265
Author(s):  
T. Baird ◽  
J.R. Fryer ◽  
S.T. Galbraith
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Bulk Material ◽  
Model Structure ◽  
Bulk Crystals ◽  
Lattice Imaging ◽  
Thin Sections ◽  
Ferric Oxyhydroxide ◽  
Resolution Electron ◽  
Hydrolysis Of

Introduction Previously we had suggested (l) that the striations observed in the pod shaped crystals of β FeOOH were an artefact of imaging in the electron microscope. Contrary to this adsorption measurements on bulk material had indicated the presence of some porosity and Gallagher (2) had proposed a model structure - based on the hollandite structure - showing the hollandite rods forming the sides of 30Å pores running the length of the crystal. Low resolution electron microscopy by Watson (3) on sectioned crystals embedded in methylmethacrylate had tended to support the existence of such pores.We have applied modern high resolution techniques to the bulk crystals and thin sections of them without confirming these earlier postulatesExperimental β FeOOH was prepared by room temperature hydrolysis of 0.01M solutions of FeCl3.6H2O, The precipitate was washed, dried in air, and embedded in Scandiplast resin. The sections were out on an LKB III Ultramicrotome to a thickness of about 500Å.

Influence of medium on alkaline hydrolysis of succinic acid monomethyl and monopropyl esters

1980 ◽  
Vol 45 (11) ◽  
pp. 2873-2882
Author(s):  
Vladislav Holba ◽  
Ján Benko
Keyword(s):  
Succinic Acid ◽  
Kinetic Parameters ◽  
Alkaline Hydrolysis ◽  
Specific Interactions ◽  
Nonaqueous Media ◽  
The Media ◽  
Kinetics Of ◽  
Hydrolysis Of

The kinetics of alkaline hydrolysis of succinic acid monomethyl and monopropyl esters were studied in mixed aqueous-nonaqueous media at various temperatures and ionic strengths. The results of measurements are discussed in terms of electrostatic and specific interactions between the reactants and other components of the reaction mixture. The kinetic parameters in the media under study are related to the influence of the cosolvent on the solvation sphere of the reactants.

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