Synthesis of N4-Substituted Derivatives of 1-[2-(Phosphonomethoxy)ethyl]cytosine and Its Diisopropyl Ester as a Model Reaction for the Synthesis of N4-Substituted Derivatives of Cidofovir

2005 ◽  
Vol 70 (12) ◽  
pp. 2066-2074 ◽  
Author(s):  
Šárka Chalupová ◽  
Antonín Holý ◽  
Milena Masojídková
Keyword(s):  
Secondary Amine ◽  
Model Reaction ◽  
Aqueous Methanol ◽  
Derivatives Of ◽  
Amine Salts

We have studied the reaction of 1-[2-(phosphonomethoxy)ethyl]cytosine (1) and its diisopropyl ester (2) with triethylammonium hydrogensulfite in 60% aqueous methanol. In the presence of some primary or secondary amine salts, at 25-70 °C, this reaction affords transaminated derivatives 4a-4e and 5a, 5b as main products accompanied by uracil compounds. However, with certain amines the reaction failed.

Fluctuations in aqueous methanol, ethanol, and propan-1-ol: amplitude and wavelength of fluctuation

1999 ◽  
Vol 77 (12) ◽  
pp. 2039-2045 ◽  
Author(s):  
Y Koga
Keyword(s):  
Isentropic Compressibility ◽  
Volume Effect ◽  
Mean Square ◽  
Aqueous Methanol ◽  
Mean Square Fluctuation ◽  
Volume Entropy ◽  
The Mean ◽  
Excess Partial Molar Enthalpy ◽  
Derivatives Of ◽  
Alcohol Alcohol

Density, heat capacity, and isentropic compressibility data for aqueous methanol, ethanol, and propan-1-ol by Benson's group were used to evaluate two kinds of fluctuations; mean-square fluctuation densities; and (mean-square) normalized fluctuations, respectively, in volume, entropy, and cross (entropy/volume) effect. The mean-square fluctuation densitiesprovide measures for the amplitude (intensity) of the fluctuation, while the normalized fluctuations contain information regarding the wavelength (extensity) of the fluctuation. Furthermore, their composition derivatives, the partial molar fluctuationsof alcohols were calculated. These quantities signify the effect of additional solute on the respective fluctuations. These data were interpreted in terms of mixing schemes learned earlier in this laboratory by using the data of excess partial molar enthalpy, entropy, and volume, and the respective alcohol-alcohol interaction functions, i.e., the composition derivatives of partial molar quantities. Key words: aqueous methanol, ethanol, and propan-1-ol;fluctuation density; normalized fluctuation; partial molar fluctuations of alcohol.

Secondary Amine Salts of Some Thiophenols

1950 ◽  
Vol 72 (9) ◽  
pp. 4281-4281 ◽  
Author(s):  
Gerald F. Grillot ◽  
Thomas J. Brooks
Keyword(s):  
Secondary Amine ◽  
Amine Salts

THE ALCOHOLYSIS OF TRIALKYLALKOXYSILANES: PART II. THE PREPARATION AND CHEMISTRY OF METHYL 2,3,4-TRI-O-TRI-METHYLSILYL-α-D-GLUCOPYRANOSIDE

1965 ◽  
Vol 43 (7) ◽  
pp. 2004-2011 ◽  
Author(s):  
D. T Hurst ◽  
A. G. McInnes
Keyword(s):  
Magnetic Resonance ◽  
Acetic Anhydride ◽  
Proton Magnetic Resonance ◽  
Benzoyl Chloride ◽  
Phenyl Isocyanate ◽  
High Yield ◽  
Aqueous Methanol ◽  
Trimethylsilyl Group ◽  
Acidic Catalysts ◽  
Derivatives Of

The trimethylsilyl group on the 6-position of methyl 2,3,4,6-tetra-O-trimethylsilyl-α-D-glucopyranoside is preferentially removed by methanolysis, using basic or acidic catalysts, giving methyl 2,3,4-tri-O-trimethylsilyl-α-D-glucopyranoside in high yield (>80%). Reaction of the latter with acetic anhydride, benzoyl chloride, or phenyl isocyanate produces the corresponding 6-substituted derivatives in quantitative yield. The trimethylsilyl residues from the latter compounds are hydrolyzed by 50% aqueous methanol with the concomitant formation of 6-O-acetyl, 6-O-benzoyl, or 6-carbanilate derivatives of methyl α-D-glucopyranoside in excellent yield. Chemical and proton magnetic resonance (p.m.r.) studies established the structure of methyl 2,3,4-tri-O-trimethylsilyl-α-D-glucopyranoside, and of subsequent derivatives prepared from this compound. Infrared and p.m.r. evidence is offered to support conclusions regarding the conformation of the groups or atoms attached to C6 and C5 of the glucoside residue in some of these compounds.

Synthesis of new derivatives of 10H-benzo[b]pyridazino[3,4-e][1,4]thiazines

2015 ◽  
Vol 21 (4) ◽  
pp. 215-218 ◽  
Author(s):  
Zahra Arghiani ◽  
Seyed Mohammad Seyedi ◽  
Mehdi Bakavoli ◽  
Mohsen Nikpour
Keyword(s):  
Secondary Amine ◽  
Inhibitory Activity ◽  
Sequential Treatment ◽  
Derivatives Of ◽  
Sodium Amide

AbstractNew 10H-benzo[b]pyridazino[3,4-e][1,4]thiazines were prepared and evaluated for inhibitory activity against soybean 15-lipoxygenase enzyme. These compounds were synthesized by the sequential treatment of 4-bromo-3,6-dichloropyridazine with 2-aminothiophenol and a secondary amine with the subsequent heterocyclization in the presence of sodium amide.

Vibrational Spectroscopy of Secondary Amine Salts: 1. Assignment of NH2+Stretching Frequencies in Crystalline Phases

2009 ◽  
Vol 113 (49) ◽  
pp. 15914-15920 ◽  
Author(s):  
Guinevere A. Giffin ◽  
Scott Boesch ◽  
Dharshani N. Bopege ◽  
Douglas R. Powell ◽  
Ralph A. Wheeler ◽  
...  
Keyword(s):  
Vibrational Spectroscopy ◽  
Secondary Amine ◽  
Crystalline Phases ◽  
Amine Salts

scholarly journals Carbapenems as water soluble organocatalysts

2018 ◽  
Vol 3 ◽  
pp. 107 ◽  
Author(s):  
Thomas L. Williams ◽  
Alexander R. Nödling ◽  
Yu-Hsuan Tsai ◽  
Louis Y. P. Luk
Keyword(s):  
Secondary Amine ◽  
Future Development ◽  
Michael Addition ◽  
Model Reaction ◽  
Water Soluble ◽  
Chiral Hplc ◽  
Chemical Transformations ◽  
H Nmr ◽  
Aqueous Environments ◽  
The Michael Addition

Background: Identification of organocatalysts functioning in aqueous environments will provide methods for more sustainable chemical transformations and allow tandem reactions with biocatalysts, like enzymes. Here we examine three water-soluble carbapenem antibiotics (meropenem, doripenem, and ertapenem) as secondary amine organocatalysts in aqueous environments. Methods: The Michael addition of nitromethane to cinnamaldehyde was used as the model reaction. The reactions were monitored by 1H NMR, and the enantioselectivity was determined by chiral HPLC.   Results: The effects of buffer components, pH, organic co-solvents and anchoring into a protein scaffold were investigated. Moderate yields of the Michael addition were obtained in buffer alone. The use of methanol as a co-solvent in a ratio of 1:1 increases the yield by 50%. Anchoring of the catalysts into a protein backbone reverses the enatioselectivity of the reaction. Conclusions: Despite only moderate yields and enantioselectivities being obtained, this study lays the foundations for future development of efficient organocatalysis in aqueous environments.

Catalyst-free Synthesis of Aminomethylphenol Derivatives in Cyclopentyl Methyl Ether via Petasis Borono-Mannich Reaction

2020 ◽  
Vol 17 ◽  
Author(s):  
Jia-Qi Di ◽  
Hao-Jie Wang ◽  
Zhen-Shui Cui ◽  
Jin-Yong Hu ◽  
Zhan-Hui Zhang
Keyword(s):  
Secondary Amine ◽  
Methyl Ether ◽  
Mannich Reaction ◽  
Phenylboronic Acid ◽  
Functional Materials ◽  
Practical Method ◽  
Model Reaction ◽  
Arylboronic Acid ◽  
Reaction Conditions ◽  
Catalyst Free

Objective: Aminomethylphenol molecules have wider applications in pharmaceuticals, agrochemicals, plant protection and promising functional materials. The development of an efficient and practical method to prepare this class of compound is highly desirable from both environmental and economical points of views. Materials and Methods: In order to establish an effective synthetic method for preparing aminomethylphenol derivatives, the Petasis borono-Mannich reaction of salicylaldehyde, phenylboronic acid and 1,2,3,4-tetrahydroisoquinoline was selected as a model reaction. A variety of reaction conditions are investigated including solvent and temperature. The generality and limitation of the established method were also evaluated. Results and Discussion: It was found that model reaction can be carried out in cyclopentyl methyl ether at 80 oC under catalyst-free condition. This protocol with a broad substrate applicability, the reaction of various arylboronic acid, secondary amine and salicylaldehyde proceeded smoothly under optimal reaction conditions to afforded various aminomethylphenol derivatives in high yields. A practical, scalable, and high-yielding synthesis of aminomethylphenol derivatives was successfully accomplished. Conclusion: A catalyst-free practical method for the synthesis of minomethylphenol derivatives based on Petasis borono– Mannich (PBM) reaction of various arylboronic acid, secondary amine and salicylaldehyde in cyclopentyl methyl ether has been developed. The salient features of this protocol are avoidance of any additive/catalyst and toxic organic solvents, use cyclopentyl methyl ether as the reaction medium, clean reaction profiles, easy operation, and high to excellent yield.

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