scholarly journals Some New Pyrido[2,3-d]pyridimines and their Nucleoside of Biological Importance

2010 ◽  
Vol 7 (s1) ◽  
pp. S85-S92 ◽  
Author(s):  
Sangeeta Tiwari ◽  
Ashok K. Yadav ◽  
A. K. Mishra
Keyword(s):  
Ammonium Acetate ◽  
Trimethylsilyl Derivative ◽  
Excellent Yield ◽  
Biological Importance ◽  
Compound Ii

Chalcones (I) reacted with malanonitrile and ammonium acetate yielded 2-amino-3-cyano-4,6-disubstituted pyridines (II) in excellent yield. 4-Amino-5,7-disubstituted pyrido [2,3-d]pyrimidine-2(1H)-thiones (III), 4-amino-5,7-disubstituted pyrido[2,3-d]pyrimidines (IV) and 4-imino-3,5,7-trisubstituted pyrido[2,3-d]pyrimidin-2(1H)-ones (V) have been synthesized by the condensation of compound (II) with thiourea, formamide and arylisocynate respectively. The ribofuranosidesviz. 4-amino-5,7-disubstituted-1- [2',3',5'-tri-o-benzoyl-β,D-ribofuranosyl]pyrido[2,3-d]pyrimidine-2-(1H)-thiones (VI) and 4-imino-3,5,7- trisubstituted-1- [2',3',5'-tri-o-benzoyl-β,D-ribofuranosyl] pyrido [2,3-d] pyrimidine-2(1H)-one (VII) were synthesized by converting compounds III and V to trimethylsilyl derivative in situ by reacting them with hexamethyldisilazane to give corresponding ribofuranosides withβ-D-ribofuranose-1-acetate-2,3,5-tribenzoate. Compounds III-V and their ribofuranosides have been screened for antimicrobial and antifungal evaluations.

Asymmetric epoxidation of alkenes catalyzed by novel chiral porphyrin metal complexes

2016 ◽  
Vol 20 (06) ◽  
pp. 730-737 ◽  
Author(s):  
Pachiannan Sakthipriya ◽  
Nallamuthu Ananthi
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Asymmetric Epoxidation ◽  
Excellent Yield ◽  
Chiral Epoxides ◽  
Epoxidation Reaction ◽  
Epoxidation Of Alkenes

Novel chiral porphyrin ligands were synthesized from four different chiral aldehydes. In situ transition metal complexes of these novel chiral porphyrin ligands were found to catalyze asymmetric epoxidation reaction of styrene possessing various substituents. The chiral epoxides were formed in excellent yield and ee.

Fe3O4@chitosan nanoparticles: a valuable heterogeneous nanocatalyst for the synthesis of 2,4,5-trisubstituted imidazoles

RSC Advances ◽  
2014 ◽  
Vol 4 (40) ◽  
pp. 20932-20939 ◽  
Author(s):  
Zohre Zarnegar ◽  
Javad Safari
Keyword(s):  
Aqueous Solution ◽  
Catalytic Activity ◽  
Ammonium Acetate ◽  
Chitosan Nanoparticles ◽  
One Pot ◽  
Heterogeneous Nanocatalyst ◽  
Aryl Aldehydes ◽  
One Pot Condensation ◽  
Co Precipitation

Chitosan-coated Fe3O4 nanoparticles (Fe3O4@CS) were prepared simply through in situ co-precipitation of Fe2+ and Fe3+ ions via NH4OH in an aqueous solution of chitosan and their catalytic activity was investigated in the synthesis of 2,4,5-trisubstituted imidazoles by a one-pot condensation of benzil derivatives, aryl aldehydes and ammonium acetate in EtOH.

Rearrangement of Quinoxalin-2-ones When Exposed to Enamines Generated in Situ from Ketones and Ammonium Acetate: Method for the Synthesis of 1-(Pyrrolyl)benzimidazolones

2015 ◽  
Vol 80 (3) ◽  
pp. 1375-1386 ◽  
Author(s):  
Vakhid A. Mamedov ◽  
Nataliya A. Zhukova ◽  
Tat’yana N. Beschastnova ◽  
Victor V. Syakaev ◽  
Dmitry B. Krivolapov ◽  
...  
Keyword(s):  
Ammonium Acetate

scholarly journals Synthesis of oxa-bridged derivatives from Diels–Alder bis-adducts of butadiene and 1,2,3,4-tetrahalo-5,5-dimethoxycyclopentadiene

2010 ◽  
Vol 6 ◽  
Author(s):  
Faiz Ahmed Khan ◽  
Karuppasamy Parasuraman
Keyword(s):  
Diels Alder ◽  
One Pot ◽  
Excellent Yield ◽  
Catalyzed Oxidation

Bis-adducts of 1,2,3,4-tetrahalo-5,5-dimethoxycyclopentadiene and 1,3-butadiene, generated in situ from 3-sulfolene, have been synthesized in excellent yield. Ruthenium catalyzed oxidation of the bis-adducts followed by a one-pot transformation of the resulting α-diketone furnished oxa-bridged compounds. Unambiguous stereochemical assignments of both diastereomeric series are reported.

scholarly journals In situ synthesis of SO3H supported Fe3O4@resorcinol–formaldehyde resin core/shell and its catalytic evaluation towards the synthesis of hexahydroquinoline derivatives in green conditions

RSC Advances ◽  
2020 ◽  
Vol 10 (68) ◽  
pp. 41703-41712
Author(s):  
Aliyeh Barzkar ◽  
Alireza Salimi Beni
Keyword(s):  
Ammonium Acetate ◽  
Aromatic Aldehydes ◽  
In Situ Synthesis ◽  
Formaldehyde Resin ◽  
One Pot ◽  
Resorcinol Formaldehyde ◽  
Resin Core ◽  
One Pot Condensation ◽  
Green Conditions

A novel core@double-shell acidic nanocatalyst (Fe3O4@SiO2@RF–SO3H) was prepared, characterized and applied in catalytic one-pot condensation between aromatic aldehydes, dimedone, malononitrile, and ammonium acetate for synthesis of hexahydroquinoline derivatives.

scholarly journals In Situ Generated Colloid Transport of Cu and Zn in Reclaimed Mine Soil Profiles Associated with Biosolids Application

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Jarrod O. Miller ◽  
Anastasios D. Karathanasis ◽  
Christopher J. Matocha
Keyword(s):  
Ammonium Acetate ◽  
Groundwater Resources ◽  
Soil Profiles ◽  
Mine Soil ◽  
Metal Release ◽  
Undisturbed Forest ◽  
Undisturbed Soils ◽  
Biosolids Application ◽  
Cu And Zn

Areas reclaimed for agricultural uses following coal mining often receive biosolids applications to increase organic matter and fertility. Transport of heavy metals within these soils may be enhanced by the additional presence of biosolids colloids. Intact monoliths from reclaimed and undisturbed soils in Virginia and Kentucky were leached to observe Cu and Zn mobility with and without biosolids application. Transport of Cu and Zn was observed in both solution and colloid associated phases in reclaimed and undisturbed forest soils, where the presence of unweathered spoil material and biosolids amendments contributed to higher metal release in solution fractions. Up to 81% of mobile Cu was associated with the colloid fraction, particularly when gibbsite was present, while only up to 18% of mobile Zn was associated with the colloid fraction. The colloid bound Cu was exchangeable by ammonium acetate, suggesting that it will release into groundwater resources.

N-p-Toluenesulfinyl imidazole: A new in situ reagent for the mild and efficient synthesis of p-toluenesulfinate alkyl esters and aryl esters

Synthesis ◽  
2021 ◽  
Author(s):  
Jessica L Shaw ◽  
Brad Austermuehle ◽  
Jordan M Witte ◽  
Timothy R Dorsey ◽  
Christina Delach ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
1H Nmr ◽  
Nmr Spectra ◽  
1H Nmr Spectra ◽  
Efficient Synthesis ◽  
Alkyl Esters ◽  
Synthetic Methodology ◽  
Excellent Yield ◽  
Rapid Formation

A new synthetic methodology has been developed for the synthesis of sulfinate alkyl and aryl esters. The methodology involves the combination of <i>p</i>-toluenesulfinic acid and 1,1’-carbonyl diimidazole (CDI) to create the putative reagent sulfinyl imidazole. The process spontaneously releases carbon dioxide upon the addition of the CDI to the acid suggesting the rapid formation of the proposed reagent. Reaction of this reagent with a series of alcohols (primary, secondary, and tertiary) afforded the corresponding sulfinate alkyl esters in good to excellent yield by the addition of alcohols. It was also possible to form the related sulfinate aryl esters by treating the proposed sulfinyl imidazole with selected phenols (phenol, <i>p</i>-tert-butylphenol, and thymol). The aryl esters were formed in excellent conversion based on analysis of the 500 MHz 1H NMR spectra of the crude reaction mixtures.

Rhodium(III)-Catalyzed C–H Activation/Alkylation of Diazabicyclic Olefins with Aryl Ketones: Facile Synthesis of Functionalized Cyclopentenes

Synlett ◽  
2018 ◽  
Vol 29 (15) ◽  
pp. 2023-2026 ◽  
Author(s):  
K. Radhakrishnan ◽  
P. Santhini ◽  
Greeshma Gopalan ◽  
A. Smrithy
Keyword(s):  
Ammonium Acetate ◽  
Bond Activation ◽  
Facile Synthesis ◽  
Reaction Proceeds ◽  
Aryl Ketones ◽  
Directing Group ◽  
Aryl Ketone

A facile synthesis of biologically important trans-functionalized cyclopentenes by a mild Rh(III)-catalyzed alkylation of strained ­diazabicyclic olefins with aryl ketones in the presence of ammonium ­acetate has been developed. The reaction proceeds through C–H bond activation of the aryl ketone groups by transforming them in to an ­autocleavable directing group, such as in situ-formed imine.

The Reaction of N-Trimethylsilyl-Substituted Heteroarylamines with Esters and Thioesters: An Efficient Protocol To Access Diheteroarylamides

Synthesis ◽  
2019 ◽  
Vol 51 (08) ◽  
pp. 1779-1790
Author(s):  
Ana Koperniku ◽  
Maryam Zamiri ◽  
David Grierson
Keyword(s):  
Parallel Synthesis ◽  
Amide Bond ◽  
Coupling Reactions ◽  
Trimethylsilyl Derivative ◽  
Vacuum Filtration ◽  
Bond Forming ◽  
Compound Libraries ◽  
Amide Coupling ◽  
Derivatives Of

The S-benzyl thioester and methyl ester derivatives of a representative 4-pyridinone-based carboxylic acid were sufficiently activated to react efficiently in amide coupling reactions with the amide anion generated in situ from the N-trimethylsilyl derivative of different weakly nucleophilic heteroarylamines. In acetonitrile as solvent, the precipitated diheteroarylamide products were isolated in pure form by vacuum filtration. This simple amide bond forming protocol can be readily adapted to the parallel synthesis of compound libraries.

Urea–Zinc Chloride Eutectic Mixture-Mediated One-Pot Synthesis of Imidazoles: Efficient and Ecofriendly Access to Trifenagrel

Synlett ◽  
2018 ◽  
Vol 30 (02) ◽  
pp. 225-229 ◽  
Author(s):  
Cristian Ochoa-Puentes ◽  
Natalia Higuera ◽  
Diana Peña-Solórzano
Keyword(s):  
Catalytic Activity ◽  
Aromatic Aldehyde ◽  
Zinc Chloride ◽  
Ammonium Acetate ◽  
Reaction Medium ◽  
Eutectic Mixture ◽  
One Pot ◽  
Dicarbonyl Compound ◽  
Excellent Yield ◽  
One Pot Synthesis

The low-melting mixture urea–ZnCl2 was evaluated as a novel reaction medium for the synthesis of imidazoles. The reaction between a dicarbonyl compound, ammonium acetate, and an aromatic aldehyde is efficiently catalyzed by the eutectic solvent, yielding a wide variety of triaryl-1H-imidazoles or 2-aryl-1H-phenanthro[9,10-d]imidazoles in good to excellent yields. In addition, the eutectic solvent was reused in five cycles without loss of its catalytic activity. This protocol was further explored for the synthesis of the drug trifenagrel, giving an excellent yield.

Sign in / Sign up

Export Citation Format

Share Document