scholarly journals Efficient Synthesis of α-Branched Purine-Based Acyclic Nucleosides: Scopes and Limitations of the Method

Molecules ◽  
2020 ◽  
Vol 25 (18) ◽  
pp. 4307
Author(s):  
Jan Frydrych ◽  
Lenka Poštová Slavětínská ◽  
Martin Dračínský ◽  
Zlatko Janeba
Keyword(s):  
Acetic Anhydride ◽  
Room Temperature ◽  
Side Chain ◽  
Efficient Synthesis ◽  
Purine Derivatives ◽  
Aliphatic Side Chain ◽  
Acyclic Nucleosides ◽  
Efficient Route ◽  
High Yields ◽  
Trimethylsilyl Trifluoromethanesulfonate

An efficient route to acylated acyclic nucleosides containing a branched hemiaminal ether moiety is reported via three-component alkylation of N-heterocycle (purine nucleobase) with acetal (cyclic or acyclic, variously branched) and anhydride (preferentially acetic anhydride). The procedure employs cheap and easily available acetals, acetic anhydride, and trimethylsilyl trifluoromethanesulfonate (TMSOTf). The multi-component reaction is carried out in acetonitrile at room temperature for 15 min and provides moderate to high yields (up to 88%) of diverse acyclonucleosides branched at the aliphatic side chain. The procedure exhibits a broad substrate scope of N-heterocycles and acetals, and, in the case of purine derivatives, also excellent regioselectivity, giving almost exclusively N-9 isomers.

scholarly journals Efficient synthesis of pyrazolopyridines containing a chromane backbone through domino reaction

2019 ◽  
Vol 15 ◽  
pp. 874-880
Author(s):  
Razieh Navari ◽  
Saeed Balalaie ◽  
Saber Mehrparvar ◽  
Fatemeh Darvish ◽  
Frank Rominger ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Selectivity ◽  
Domino Reaction ◽  
Primary Amines ◽  
Efficient Synthesis ◽  
Atom Economy ◽  
Reaction Conditions ◽  
Efficient Approach ◽  
Three Component Reaction ◽  
High Yields

An efficient approach for the synthesis of pyrazolopyridines containing the aminochromane motif through a base-catalyzed cyclization reaction is reported. The synthesis was carried out through a three-component reaction of (arylhydrazono)methyl-4H-chromen-4-one, malononitrile, primary amines in the presence of Et3N at room temperature. However, carrying out the reaction under the same conditions without base led to a fused chromanyl-cyanopyridine. High selectivity, high atom economy, and good to high yields in addition to mild reaction conditions are the advantages of this approach.

SiO2·12WO3·24H2O: a Highly Efficient Catalyst for the Synthesis of 5-Arylidene Barbituric Acid in the Presence of Water

2009 ◽  
Vol 62 (4) ◽  
pp. 353 ◽  
Author(s):  
Ji-Tai Li ◽  
Ming-Xuan Sun
Keyword(s):  
Room Temperature ◽  
Barbituric Acid ◽  
Aqueous Media ◽  
Aromatic Aldehydes ◽  
Efficient Catalyst ◽  
Highly Efficient ◽  
Efficient Route ◽  
Acid Catalyzed ◽  
High Yields

The condensation of aromatic aldehydes and barbituric acid catalyzed by SiO2·12WO3·24H2O in aqueous media at room temperature gave 5-arylidene barbituric acid in high yields with or without the use of ultrasound, providing a simple and efficient route to synthesis of these compounds.

CuI/Et2NH-Catalyzed One-Pot Highly Efficient Synthesis of 1,4-Disubstituted 1,2,3-Triazoles in Green Solvent Glycerol

Synthesis ◽  
2018 ◽  
Vol 50 (11) ◽  
pp. 2191-2199 ◽  
Author(s):  
Yongde Zhao ◽  
Shengqiang Guo ◽  
Yang Zhou ◽  
Bencai Dai ◽  
Cuimeng Huo ◽  
...  
Keyword(s):  
Catalytic System ◽  
Sodium Azide ◽  
Room Temperature ◽  
Green Solvent ◽  
Efficient Synthesis ◽  
One Pot ◽  
Highly Efficient ◽  
Three Component Reaction ◽  
Efficient Route ◽  
Terminal Acetylenes

A concise one-pot three-component reaction of organic halides­, terminal acetylenes, and sodium azide provided an efficient route for the synthesis of 1,2,3-triazoles. A variety of 1,2,3-triazoles were prepared in good to excellent yields with green solvent glycerol. This procedure used CuI and diethylamine, which are two easily available reagents as the new catalytic system at room temperature.

Adduct Intermediates in the Side-chain Nitration of 1,4-Dimethylnaphthalene

1972 ◽  
Vol 50 (24) ◽  
pp. 3988-3992 ◽  
Author(s):  
Alfred Fischer ◽  
Alan Leslie Wilkinson
Keyword(s):  
Acetic Acid ◽  
Nitric Acid ◽  
Acetic Anhydride ◽  
Room Temperature ◽  
Methylene Chloride ◽  
Side Chain ◽  
Trans Isomers ◽  
Cis And Trans Isomers ◽  
Cis And Trans ◽  
Naphthyl Acetate

cis and trans isomers of 1,4-dimethyl-4-nitro-1,4-dihydro-1-naphthyl acetate (1) have been isolated from a mixture of 1,4-dimethylnaphthalene and nitric acid in acetic anhydride by quenching at −40°. At room temperature only 1-methyl-4-nitromethylnaphthalene (4) is obtained. The conversion of 1,4-dimethylnaphthalene to 4 and of the cis (1a) and trans (1b) adducts to 4, by nitric acid in acetic anhydride, has been followed by n.m.r. 1,4-Dimethyl-4-nitro-1,4-dihydro-1-naphthyl nitrate (5) appears to be the immediate product from nitration of 1,4-dimethylnaphthalene in acetic anhydride, methylene chloride, or nitromethane. In acetic anhydride 5 is converted into 1. Decomposition of 1 in acetic acid gives 1,4-dimethyl-2-naphthyl acetate and some 4. The formation of 4 in this reaction is suppressed by urea.

Efficient Synthesis of Indole Derivatives Containing the Tetrazole Moeity Utilizing an Ugi-Azide Post-Transformation Strategy

Synlett ◽  
2018 ◽  
Vol 29 (14) ◽  
pp. 1892-1896 ◽  
Author(s):  
Saeed Balalaie ◽  
Ali Nikbakht ◽  
Fatemeh Baghestani ◽  
Frank Rominger
Keyword(s):  
Room Temperature ◽  
Functional Group ◽  
Cyclization Reaction ◽  
Indole Derivatives ◽  
Efficient Synthesis ◽  
Efficient Strategy ◽  
High Yields ◽  
Operational Simplicity ◽  
Transformation Strategy

An efficient strategy has been developed for the synthesis of indole derivatives containing the tetrazole moiety using a AuCl3-catalyzed cyclization reaction. The precursors of the cycloadduct were easily prepared by an Ugi-azide 4-CR in methanol at room temperature. The merit of this protocol lies in its operational simplicity, readily available starting materials, high yields of product, and good functional group tolerance.

Iodine-catalyzed efficient synthesis of chalcones by grinding under solvent-free conditions

2009 ◽  
Vol 87 (9) ◽  
pp. 1209-1212 ◽  
Author(s):  
Hongshe Wang ◽  
June Zeng
Keyword(s):  
Organic Synthesis ◽  
Room Temperature ◽  
Biological Activities ◽  
Aromatic Aldehydes ◽  
Solvent Free ◽  
Efficient Synthesis ◽  
Solvent Free Conditions ◽  
High Yields

Chalcones are useful intermediates in organic synthesis and exhibit a large number of different biological activities. Chalcones have been synthesized in high yields by Claisen–Schmidt condensation of substituted acetophenones with various aromatic aldehydes in the presence of 10 mol% of iodine at room temperature by grinding under solvent-free conditions.

Task-specific ionic-liquid-catalyzed efficient synthesis of indole derivatives under solvent-free conditions

2010 ◽  
Vol 88 (2) ◽  
pp. 150-154 ◽  
Author(s):  
Sudarshan Das ◽  
Matiur Rahman ◽  
Dhiman Kundu ◽  
Adinath Majee ◽  
Alakananda Hajra
Keyword(s):  
Ionic Liquid ◽  
Room Temperature ◽  
Acid Catalyst ◽  
Significant Loss ◽  
Solvent Free ◽  
Indole Derivatives ◽  
Efficient Synthesis ◽  
Solvent Free Conditions ◽  
High Yields ◽  
Task Specific Ionic Liquid

A sulfonic-acid-functionalized ionic liquid is used as a Brønsted acid catalyst for the efficient synthesis of indole derivatives in good-to-high yields at room temperature under solvent-free conditions. The catalyst can be reused for ten consecutive runs without significant loss of activity.

Efficient synthesis and biological properties of the 2′-trifluoromethyl analogues of acyclic nucleosides and acyclic nucleoside phosphonates

2011 ◽  
Vol 76 (10) ◽  
pp. 1187-1198 ◽  
Author(s):  
Petr Jansa ◽  
Viktor Kolman ◽  
Alexandra Kostinová ◽  
Martin Dračínský ◽  
Helena Mertlíková-Kaiserová ◽  
...  
Keyword(s):  
Biological Properties ◽  
Trifluoromethyl Group ◽  
Efficient Synthesis ◽  
Phosphonic Acids ◽  
Acyclic Nucleosides ◽  
Acyclic Nucleoside Phosphonates ◽  
Dialkyl Phosphonates ◽  
Acyclic Nucleoside ◽  
High Yields ◽  
Very High

Efficient and optimized procedure for the preparation of several acyclic nucleosides and acyclic nucleoside phosphonates substituted at the C-2′ position of the aliphatic part by the trifluoromethyl group is described. Trifluoromethyloxirane was found to be an excellent reagent for the introduction of the 1,1,1-trifluoropropan-2-ol moiety. Surprisingly, the next reaction of these 1,1,1-trifluoropropan-2-ols with the reagent for the introduction of the methylphosphonic residue afforded the desired phosphonates in very high yields and finally a novel simple and scalable procedure for the isolation of free phosphonic acids, after the reaction of dialkyl phosphonates with bromotrimethylsilane, was developed. Prepared compounds were evaluated for their biological properties, but none of the prepared phosphonic acids or acyclic nucleosides exhibits any antiviral, antiproliferative or anti-toxin activities.

scholarly journals An Efficient Greener Approach for N-acylation of Amines in Water Using Benzotriazole Chemistry

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2501 ◽  
Author(s):  
Tarek S. Ibrahim ◽  
Israa A. Seliem ◽  
Siva S. Panda ◽  
Amany M. M. Al-Mahmoudy ◽  
Zakaria K. M. Abdel-Samii ◽  
...  
Keyword(s):  
Amino Acid ◽  
Reaction Time ◽  
Microwave Irradiation ◽  
Room Temperature ◽  
Efficient Synthesis ◽  
Short Reaction Time ◽  
Mild Conditions ◽  
Drug Conjugates ◽  
Cost Efficient ◽  
High Yields

A straightforward, mild and cost-efficient synthesis of various arylamides in water was accomplished using versatile benzotriazole chemistry. Acylation of various amines was achieved in water at room temperature as well as under microwave irradiation. The developed protocol unfolds the synthesis of amino acid aryl amides, drug conjugates and benzimidazoles. The environmentally friendly synthesis, short reaction time, simple workup, high yields, mild conditions and free of racemization are the key advantages of this protocol.

scholarly journals Efficient synthesis of polyfunctionalized carbazoles and pyrrolo[3,4-c]carbazoles via domino Diels–Alder reaction

2021 ◽  
Vol 17 ◽  
pp. 2425-2432
Author(s):  
Ren-Jie Fang ◽  
Chen Yan ◽  
Jing Sun ◽  
Ying Han ◽  
Chao-Guo Yan
Keyword(s):  
Room Temperature ◽  
Alder Reaction ◽  
Diels Alder ◽  
Efficient Synthesis ◽  
One Pot ◽  
Diels Alder Reaction ◽  
Acid Catalyzed ◽  
The One ◽  
High Yields ◽  
Ddq Oxidation

The p-TsOH-catalyzed Diels–Alder reaction of 3-(indol-3-yl)maleimides with chalcone in toluene at 60 °C afforded two diastereoisomers of tetrahydropyrrolo[3,4-c]carbazoles, which can be dehydrogenated by DDQ oxidation in acetonitrile at room temperature to give the aromatized pyrrolo[3,4-c]carbazoles in high yields. On the other hand, the one-pot reaction of 3-(indol-3-yl)-1,3-diphenylpropan-1-ones with chalcones or benzylideneacetone in acetonitrile in the presence of p-TsOH and DDQ resulted in polyfunctionalized carbazoles in satisfactory yields. The reaction mechanism included the DDQ oxidative dehydrogenation of 3-(indol-3-yl)-1,3-diphenylpropan-1-ones to the corresponding 3-vinylindoles, their acid-catalyzed Diels–Alder reaction and sequential aromatization process.

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