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Jai Narain Vishwakarma - One of the best experts on this subject based on the ideXlab platform.
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Design, synthesis, structure elucidation, and biological activities of 3-(substituted amino)-1-(pyridin-4-yl)propenones and 5-isonicotinoyl-1,2,3,4-Tetrahydropyrimidine–adamantane hybrids
Monatshefte für Chemie - Chemical Monthly, 2017Co-Authors: Utpalparna Kalita, Shunan Kaping, Revinus Nongkynrih, Ivee Boiss, Laishram Indira Singha, Jai Narain VishwakarmaAbstract:Novel molecular hybrids of 5-isonicotinoyl-1,2,3,4-Tetrahydropyrimidine–adamantane have been synthesized in excellent yields by the reaction of enaminones, 1-adamantanamine, and formaldehyde. Enaminones (Z)-3-alkyl/aralkyl/aryl-1-(pyridin-4-yl)prop-2-en-1-ones have been synthesised by the reaction of 4-acetylpyridine with N,N-dimethylformamide dimethyl acetal and its bioassay test showed good anti-inflammatory property, but no zone of growth inhibition against Bacillus subtilis (MTCC Code-121), Staphylococcus aureus (MTCC Code-9886), Escherichia coli (MTCC Code-1302), and Salmonella enterica (MTCC Code-3232) bacterial strains. The structures of the synthesized compounds have been established with the help of spectral and analytical data. X-ray analysis of a representative candidate of the series 5-isonicotinoyl-1,2,3,4-Tetrahydropyrimidine–adamantane was done for the final confirmation of the structure.Graphical abstract
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Catalyst-free multicomponent synthesis of novel adamantyl-containing Tetrahydropyrimidine carboxylates
Molecular Diversity, 2016Co-Authors: Utpalparna Kalita, Shunan Kaping, Jai Narain VishwakarmaAbstract:$$\beta $$ β -Enaminoesters were generated in situ by the reaction of aliphatic or aromatic primary amines to electron-deficient alkynes, dimethyl acetylenedicarboxylate, and methyl propiolate. $$\beta $$ β -Enaminoesters thus formed were reacted with 1-adamantanamine and formaldehyde in methanol to give novel molecular hybrids: dimethyl 3-((3s,5s,7s)-adamantan-1-yl)-1-(alkyl/aralkyl/aryl)-1,2,3,4-Tetrahydropyrimidine-5,6-dicarboxylates ( 5a – j ) and methyl 3-((3s,5s,7s)-adamantan-1-yl)-1-(alkyl/aralkyl/aryl)-1,2,3,4-Tetrahydropyrimidine-5-carboxylates ( 9a – j ). The structures of the molecular hybrids have been established based on the spectral and analytical data. Structural confirmation of the products was done by X-ray crystallography of 5d as a representative product of the series. Graphical Abstract
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Catalyst-free multicomponent synthesis of novel adamantyl-containing Tetrahydropyrimidine carboxylates.
Molecular diversity, 2016Co-Authors: Utpalparna Kalita, Shunan Kaping, Jai Narain VishwakarmaAbstract:[Formula: see text]-Enaminoesters were generated in situ by the reaction of aliphatic or aromatic primary amines to electron-deficient alkynes, dimethyl acetylenedicarboxylate, and methyl propiolate. [Formula: see text]-Enaminoesters thus formed were reacted with 1-adamantanamine and formaldehyde in methanol to give novel molecular hybrids: dimethyl 3-((3s,5s,7s)-adamantan-1-yl)-1-(alkyl/aralkyl/aryl)-1,2,3,4-Tetrahydropyrimidine-5,6-dicarboxylates (5a-j) and methyl 3-((3s,5s,7s)-adamantan-1-yl)-1-(alkyl/aralkyl/aryl)-1,2,3,4-Tetrahydropyrimidine-5-carboxylates (9a-j). The structures of the molecular hybrids have been established based on the spectral and analytical data. Structural confirmation of the products was done by X-ray crystallography of 5d as a representative product of the series.
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Novel Tetrahydropyrimidine–adamantane hybrids as anti-inflammatory agents: synthesis, structure and biological evaluation
Medicinal Chemistry Research, 2015Co-Authors: Utpalparna Kalita, Shunan Kaping, Revinus Nongkynrih, Laishram Indira Singha, Jai Narain VishwakarmaAbstract:A series of novel (3-((3s,5s,7s)-adamantan-1-yl)-1-alkyl/aralkyl/aryl-1,2,3,4-tetrahydroyrimidin-5-yl)(aryl)methanones (5a–j) has been synthesized by the reaction of 1-aryl-3-(alkyl/aralkyl/aryl)aminoprop-2-en-1-ones 3a–j, 1-adamantanamine 4 and formaldehyde under thermal conditions. The structures of the products (5a–j) have been established with the help of spectral and analytical data. The stereochemistry of the products was established by X-ray crystallographic studies of a representative product (3-((3s,5s,7s)-adamantan-1-yl)-1-methyl-1,2,3,4-tetrahydropyrimidin-5-yl)(4-chlorophenyl) methanone (5g) of the series. The target adamantane–Tetrahydropyrimidine hybrids 5a–j were evaluated for their anti-inflammatory activities as a result of which compounds 5e (R=C6H5CH2, Ar=C6H5), 5i (R=CH3, Ar=4-CH3C6H4), 5j (R=C6H5CH2, Ar=4-CH3C6H4) and 5g (R=CH3, Ar=4-ClC6H4) were found to exhibit excellent and promising anti-inflammatory activities.
Utpalparna Kalita - One of the best experts on this subject based on the ideXlab platform.
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Design, synthesis, structure elucidation, and biological activities of 3-(substituted amino)-1-(pyridin-4-yl)propenones and 5-isonicotinoyl-1,2,3,4-Tetrahydropyrimidine–adamantane hybrids
Monatshefte für Chemie - Chemical Monthly, 2017Co-Authors: Utpalparna Kalita, Shunan Kaping, Revinus Nongkynrih, Ivee Boiss, Laishram Indira Singha, Jai Narain VishwakarmaAbstract:Novel molecular hybrids of 5-isonicotinoyl-1,2,3,4-Tetrahydropyrimidine–adamantane have been synthesized in excellent yields by the reaction of enaminones, 1-adamantanamine, and formaldehyde. Enaminones (Z)-3-alkyl/aralkyl/aryl-1-(pyridin-4-yl)prop-2-en-1-ones have been synthesised by the reaction of 4-acetylpyridine with N,N-dimethylformamide dimethyl acetal and its bioassay test showed good anti-inflammatory property, but no zone of growth inhibition against Bacillus subtilis (MTCC Code-121), Staphylococcus aureus (MTCC Code-9886), Escherichia coli (MTCC Code-1302), and Salmonella enterica (MTCC Code-3232) bacterial strains. The structures of the synthesized compounds have been established with the help of spectral and analytical data. X-ray analysis of a representative candidate of the series 5-isonicotinoyl-1,2,3,4-Tetrahydropyrimidine–adamantane was done for the final confirmation of the structure.Graphical abstract
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Catalyst-free multicomponent synthesis of novel adamantyl-containing Tetrahydropyrimidine carboxylates
Molecular Diversity, 2016Co-Authors: Utpalparna Kalita, Shunan Kaping, Jai Narain VishwakarmaAbstract:$$\beta $$ β -Enaminoesters were generated in situ by the reaction of aliphatic or aromatic primary amines to electron-deficient alkynes, dimethyl acetylenedicarboxylate, and methyl propiolate. $$\beta $$ β -Enaminoesters thus formed were reacted with 1-adamantanamine and formaldehyde in methanol to give novel molecular hybrids: dimethyl 3-((3s,5s,7s)-adamantan-1-yl)-1-(alkyl/aralkyl/aryl)-1,2,3,4-Tetrahydropyrimidine-5,6-dicarboxylates ( 5a – j ) and methyl 3-((3s,5s,7s)-adamantan-1-yl)-1-(alkyl/aralkyl/aryl)-1,2,3,4-Tetrahydropyrimidine-5-carboxylates ( 9a – j ). The structures of the molecular hybrids have been established based on the spectral and analytical data. Structural confirmation of the products was done by X-ray crystallography of 5d as a representative product of the series. Graphical Abstract
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Catalyst-free multicomponent synthesis of novel adamantyl-containing Tetrahydropyrimidine carboxylates.
Molecular diversity, 2016Co-Authors: Utpalparna Kalita, Shunan Kaping, Jai Narain VishwakarmaAbstract:[Formula: see text]-Enaminoesters were generated in situ by the reaction of aliphatic or aromatic primary amines to electron-deficient alkynes, dimethyl acetylenedicarboxylate, and methyl propiolate. [Formula: see text]-Enaminoesters thus formed were reacted with 1-adamantanamine and formaldehyde in methanol to give novel molecular hybrids: dimethyl 3-((3s,5s,7s)-adamantan-1-yl)-1-(alkyl/aralkyl/aryl)-1,2,3,4-Tetrahydropyrimidine-5,6-dicarboxylates (5a-j) and methyl 3-((3s,5s,7s)-adamantan-1-yl)-1-(alkyl/aralkyl/aryl)-1,2,3,4-Tetrahydropyrimidine-5-carboxylates (9a-j). The structures of the molecular hybrids have been established based on the spectral and analytical data. Structural confirmation of the products was done by X-ray crystallography of 5d as a representative product of the series.
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Novel Tetrahydropyrimidine–adamantane hybrids as anti-inflammatory agents: synthesis, structure and biological evaluation
Medicinal Chemistry Research, 2015Co-Authors: Utpalparna Kalita, Shunan Kaping, Revinus Nongkynrih, Laishram Indira Singha, Jai Narain VishwakarmaAbstract:A series of novel (3-((3s,5s,7s)-adamantan-1-yl)-1-alkyl/aralkyl/aryl-1,2,3,4-tetrahydroyrimidin-5-yl)(aryl)methanones (5a–j) has been synthesized by the reaction of 1-aryl-3-(alkyl/aralkyl/aryl)aminoprop-2-en-1-ones 3a–j, 1-adamantanamine 4 and formaldehyde under thermal conditions. The structures of the products (5a–j) have been established with the help of spectral and analytical data. The stereochemistry of the products was established by X-ray crystallographic studies of a representative product (3-((3s,5s,7s)-adamantan-1-yl)-1-methyl-1,2,3,4-tetrahydropyrimidin-5-yl)(4-chlorophenyl) methanone (5g) of the series. The target adamantane–Tetrahydropyrimidine hybrids 5a–j were evaluated for their anti-inflammatory activities as a result of which compounds 5e (R=C6H5CH2, Ar=C6H5), 5i (R=CH3, Ar=4-CH3C6H4), 5j (R=C6H5CH2, Ar=4-CH3C6H4) and 5g (R=CH3, Ar=4-ClC6H4) were found to exhibit excellent and promising anti-inflammatory activities.
Aditya Bhattacharyya - One of the best experts on this subject based on the ideXlab platform.
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Synthetic Routes to 1,4,5,6-Tetrahydropyrimidines: An Overview and Recent Advances
Current Organic Chemistry, 2019Co-Authors: Aditya BhattacharyyaAbstract:Partially reduced heterocyclic compounds such as 1,4,5,6-Tetrahydropyrimidines are often found to possess interesting pharmacological properties. Yet, the synthetic routes towards such systems are less developed than their fully aromatic counterparts. In this review article, the biological significance of 1,4,5,6-Tetrahydropyrimidines is discussed and the existing literature reports describing various preparative routes to access 1,4,5,6-Tetrahydropyrimidine derivatives have been categorically described. The focus has been expanded to present an overview of the chronological development of the traditional synthetic routes as well as the contemporary approaches to 1,4,5,6-Tetrahydropyrimidines that generally include: (i) condensation reactions of diamines with various appropriate counterparts such as carbonyl compounds, imino ethers, amidines or nitriles, condensation of amidines with 1,3-dibromopropane and α,β-unstaurated carbonyl compounds, condensation of amino alcohols; (ii) selective reduction of pyrimidines; (iii) ring expansion chemistry of cyclopropanes, aziridines, and azetidines; and (iv) miscellaneous examples such as various multicomponent reactions.
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Stereospecific Synthesis of 1,4,5,6-Tetrahydropyrimidines via Domino Ring-Opening Cyclization of Activated Aziridines with α-Acidic Isocyanides
Organic letters, 2018Co-Authors: Aditya Bhattacharyya, Chandan Kumar Shahi, Sajan Pradhan, Manas K. GhoraiAbstract:An expeditious synthetic route to access structurally diverse 1,4,5,6-Tetrahydropyrimidines via domino ring-opening cyclization of activated aziridines with α-acidic isocyanides has been established. The transformation proceeds via Lewis acid mediated SN2-type ring opening of activated aziridines with α-carbanion of the isocyanides followed by a concomitant 6-endo-dig cyclization in a domino fashion to furnish the 1,4,5,6-Tetrahydropyrimidine derivatives in excellent yields (up to 84%) and also in diastereo- and enantiomerically pure form (dr >99:1, ee >99%).
Aleksei Yu. Kuznetsov - One of the best experts on this subject based on the ideXlab platform.
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A New Convenient Synthesis of 5-Acyl-1,2,3,4-Tetrahydropyrimidine-2-thiones/ones
Molecules, 1998Co-Authors: A. D. Shutalev, Ekaterina A. Kishko, Natalie Sivova, Aleksei Yu. KuznetsovAbstract:Anatoly D. Shutalev*, Ekaterina A. Kishko, Natalie V. Sivova and Aleksei Yu. KuznetsovDepartment of Organic Chemistry, State Academy of Fine Chemical Technology, Vernadsky Ave. 86, Moscow 117571,Russian Federation, FAX +7-095-431-6332 (shutalev@orc.ru)Received: 28 January 1998 / Accepted: 18 February 1998 / Published: 9 March 1998Abstract: An efficient one-pot synthesis of 5-acyl-1,2,3,4-Tetrahydropyrimidine-2-thiones/ones is described.The synthesis is based on the reaction of readily available α-tosyl substituted thioureas or ureas with enolatesof β-oxoesters or 1,3-dicarbonyl compounds followed by acid-catalyzed dehydration of the obtained 5-acyl-4-hydroxyhexahydropyrimidine-2-thiones/ones.Keywords: α -Tosyl substituted (thio)ureas, 5-acyl-1,2,3,4-Tetrahydropyrimidine-2-thiones/ones.IntroductionIn recent years 5-acyl-1,2,3,4-Tetrahydropyrimidine-2-thiones/ones (“Biginelli compounds”, i.e., 5a-h ) receivedsignificant attention owing to their diverse range ofbiological properties. For example, some of thesecompounds are very potent calcium channel blockers [1].The presence of several interacting functional groups inBiginelli compounds also determines their great syntheticpotential [2].At the present time there are a few general methods forthe synthesis of 5-acyl-1,2,3,4-Tetrahydropyrimidine-2-thiones/ones. One of them is the Biginelli reaction [2,3].This very simple method involves acid-catalyzed three-component condensation of (thio)ureas, aldehydes and β-oxoesters or 1,3-dicarbonyl compounds. The maindisadvantage of this synthesis is quite often low yields ofthe desired pyrimidines because various side reactionsoccur. For instance, the reaction of urea and ethylacetoacetate with aliphatic aldehydes gives ethyl 4-alkyl-2-oxo-1,2,3,4-Tetrahydropyrimidine-5-carboxylates in yieldsless than 30-40 % [4]. A very attractive approach to thesynthesis of Biginelli compounds has been developed byAtwal and co-workers [5]. This approach is based on thereaction of α-arylidene- β -oxoesters with S-(4-methoxybenzyl)isothiourea or O-methylisourea in thepresence of sodium bicarbonate followed bytransformation of the obtained 2-(4-methoxybenzylthio)-or 2-methoxy-1,4-dihydropyrimidine-5-carboxylates into2-thioxo- or 2-oxo-1,2,3,4-Tetrahydropyrimidine-5-carboxylates.Recently we have demonstrated [6,7] that Biginellicompounds can be easily prepared by reaction of α-azidoor α-tosyl substituted thioureas and ureas with sodiumenolates of β-oxoesters or 1,3-dicarbonyl compoundsfollowed by acid-catalyzed dehydration of the obtained 5-acyl-4-hydroxyhexahydropyrimidine-2-thiones/ones. Boththese stages of synthesis proceed under mild conditionsand usually in high yields. This method is very flexible andmakes it possible to prepare a large number of 1,2,3,4-Tetrahydropyrimidine-2-thiones/ones bearing varioussubstituents in the pyrimidine ring.
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a new convenient synthesis of 5 acyl 1 2 3 4 Tetrahydropyrimidine 2 thiones ones
Molecules, 1998Co-Authors: A. D. Shutalev, Ekaterina A. Kishko, Natalie Sivova, Aleksei Yu. KuznetsovAbstract:Anatoly D. Shutalev*, Ekaterina A. Kishko, Natalie V. Sivova and Aleksei Yu. KuznetsovDepartment of Organic Chemistry, State Academy of Fine Chemical Technology, Vernadsky Ave. 86, Moscow 117571,Russian Federation, FAX +7-095-431-6332 (shutalev@orc.ru)Received: 28 January 1998 / Accepted: 18 February 1998 / Published: 9 March 1998Abstract: An efficient one-pot synthesis of 5-acyl-1,2,3,4-Tetrahydropyrimidine-2-thiones/ones is described.The synthesis is based on the reaction of readily available α-tosyl substituted thioureas or ureas with enolatesof β-oxoesters or 1,3-dicarbonyl compounds followed by acid-catalyzed dehydration of the obtained 5-acyl-4-hydroxyhexahydropyrimidine-2-thiones/ones.Keywords: α -Tosyl substituted (thio)ureas, 5-acyl-1,2,3,4-Tetrahydropyrimidine-2-thiones/ones.IntroductionIn recent years 5-acyl-1,2,3,4-Tetrahydropyrimidine-2-thiones/ones (“Biginelli compounds”, i.e., 5a-h ) receivedsignificant attention owing to their diverse range ofbiological properties. For example, some of thesecompounds are very potent calcium channel blockers [1].The presence of several interacting functional groups inBiginelli compounds also determines their great syntheticpotential [2].At the present time there are a few general methods forthe synthesis of 5-acyl-1,2,3,4-Tetrahydropyrimidine-2-thiones/ones. One of them is the Biginelli reaction [2,3].This very simple method involves acid-catalyzed three-component condensation of (thio)ureas, aldehydes and β-oxoesters or 1,3-dicarbonyl compounds. The maindisadvantage of this synthesis is quite often low yields ofthe desired pyrimidines because various side reactionsoccur. For instance, the reaction of urea and ethylacetoacetate with aliphatic aldehydes gives ethyl 4-alkyl-2-oxo-1,2,3,4-Tetrahydropyrimidine-5-carboxylates in yieldsless than 30-40 % [4]. A very attractive approach to thesynthesis of Biginelli compounds has been developed byAtwal and co-workers [5]. This approach is based on thereaction of α-arylidene- β -oxoesters with S-(4-methoxybenzyl)isothiourea or O-methylisourea in thepresence of sodium bicarbonate followed bytransformation of the obtained 2-(4-methoxybenzylthio)-or 2-methoxy-1,4-dihydropyrimidine-5-carboxylates into2-thioxo- or 2-oxo-1,2,3,4-Tetrahydropyrimidine-5-carboxylates.Recently we have demonstrated [6,7] that Biginellicompounds can be easily prepared by reaction of α-azidoor α-tosyl substituted thioureas and ureas with sodiumenolates of β-oxoesters or 1,3-dicarbonyl compoundsfollowed by acid-catalyzed dehydration of the obtained 5-acyl-4-hydroxyhexahydropyrimidine-2-thiones/ones. Boththese stages of synthesis proceed under mild conditionsand usually in high yields. This method is very flexible andmakes it possible to prepare a large number of 1,2,3,4-Tetrahydropyrimidine-2-thiones/ones bearing varioussubstituents in the pyrimidine ring.
İsmail Özdemir - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and characterization of N-substituted 1,4,5,6-Tetrahydropyrimidine containing functional polymers as SO2 and CO2 sorbents
Journal of Polymer Science Part A: Polymer Chemistry, 1997Co-Authors: Turgay Seçkin, Bülent Alıcı, Engin Cetinkaya, İsmail ÖzdemirAbstract:Novel vinyl monomers containing 1,4,5,6-Tetrahydropyrimidine were prepared by the reaction of N-substituted-1,3-diaminopropane with N,N-dimethyl-formamide dimethylacetal, which gave 1-alkyl or aryl substituted 1,4,5,6-Tetrahydropyrimidines, Alkylation of the Tetrahydropyrimidine derivatives by chloromethylstyrene produces the N-methyl-N′-vinyl benzyl-1,4,5,6-tetrahydropyrimidinium chloride in high yields. These monomers were readily polymerized in dimethylformamide by AIBN at 80°C. Homopolymers and soluble linear copolymers were prepared and copolymerization parameters were rationalized. Further, insoluble terpolymers prepared from these monomers, styrene and divinylbenzene were tested for the sorption of the weakly acidic gases gave excellent results. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2411–2420, 1997
