Syntheses, Complexation and Biological Activity of Aminopyridines: A Mini-Review
Kingsley John Orie,
Remy Ukachukwu Duru,
Raphael I-oro Ngochindo
Issue:
Volume 7, Issue 2, December 2021
Pages:
11-25
Received:
19 June 2021
Accepted:
1 July 2021
Published:
9 July 2021
Abstract: Aminopyridines are among the classes of heterocyclic compounds that have been extensively studied in the last few decades owing to their interesting biological activities. They exist in three isomeric forms: 2-aminopyridine, 3-aminopyridine and 4-aminopyridine. The diversity in their pharmacological activities has attracted the attention of many researchers to explore the reasons for their wide potential. This study examines recent advances related to the efficient procedure for synthesizing different types of aminopyridine derivatives, its coordination site with metals and biological activities using systematic literature review and content analysis. Other important concepts of aminopyridines discussed are basicity, electric hindrance as related to percentage yield of isomeric forms and spectra updates on the characterization of aminopyridines. The findings from this study also reveal the array of solvents used for purification processes; ideas on isomers that have not been used in the synthesis of aminopyridine derivatives and their respective biological activities. The significance of this study is on the various synthetic methods revealed, which may be helpful to the development of newer compounds with aminopyridines moieties that could offer high bioactivity and lesser toxicity.
Abstract: Aminopyridines are among the classes of heterocyclic compounds that have been extensively studied in the last few decades owing to their interesting biological activities. They exist in three isomeric forms: 2-aminopyridine, 3-aminopyridine and 4-aminopyridine. The diversity in their pharmacological activities has attracted the attention of many re...
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3-Oxobutanamides in Heterocyclic Synthesis: Synthesis, Antimicrobial and Antioxidant Activity of Pyridine, Thiophene, Diazepine and Thiazole Derivatives
Sayed Abd El-moneim Ahmed Altaweel,
Ahmed Abdelhameed Khames,
Abu-Bakr Abdelhady Mohamed El-Adasy,
Abdallah Mahmoud Ahmed Hassane,
Abdel-Haleem Mostafa Hussein
Issue:
Volume 7, Issue 2, December 2021
Pages:
26-32
Received:
18 March 2021
Accepted:
9 July 2021
Published:
15 July 2021
Abstract: In the last few years we and others reported a variety of synthesis of heteroaromatics that have been developed utilizing β–oxoanilides as readily obtainable compounds. In this study, treatment of 3-Oxobutanamides 1 with phenyl isocyanate at room temperature in basic medium and DMF afforded thiocarbamoyl derivative 3 through intermediate 2 upon treatment with dilute HCl. The non-isolable potassium salt 2 was allowed to react with α-halo carbonyl compounds such as ethyl chloroacetate and chloroacetonitrile in dry DMF at room temperature to furnished thiophene 6 and thiazole derivative 9 respectively. Compound 6 was treated with hydrazine hydrate in ethanol to yield thiophene-5-carbohydrazide derivative 7. Also, compound 1 reacted with malononitrile and sulfur element in refluxing absolute ethanol and triethylamine to yield thiophene derivative 11, which reacted with formic acid and α-chloro acetylchloride to give thieno[2,3-d]pyrimidine derivative 12 and chloro acetamide derivative 13. Treatment of compound 13 with ammonium thiocyanate led to thiazolo[3,2-a]thieno[2,3-d]pyrimidine derivative 15 through non-isolable 14. Also, condensation of 1 with malononitrile and ethylene diamine afforded the pyridine derivative 17 and 1,4-diazepine derivative 18. The structures and formulas of all the synthesized compounds were supported by spectral data. Some of the synthesized compounds were evaluated for their antibacterial and antioxidant activity. These compounds showed different degrees of activity.
Abstract: In the last few years we and others reported a variety of synthesis of heteroaromatics that have been developed utilizing β–oxoanilides as readily obtainable compounds. In this study, treatment of 3-Oxobutanamides 1 with phenyl isocyanate at room temperature in basic medium and DMF afforded thiocarbamoyl derivative 3 through intermediate 2 upon tre...
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Some Aspects of the Reactivity of 3-acyl-4-hydroxycoumarins
Youssoufou Bakouan,
Bintou Sessouma,
Têeda Hamidou Ganamé,
Lassané Tarpaga,
Jules Yoda,
Karifa Bayo
Issue:
Volume 7, Issue 2, December 2021
Pages:
33-38
Received:
8 November 2021
Accepted:
2 December 2021
Published:
7 December 2021
Abstract: Coumarins are the most important oxygenated heterocyclic of natural compounds. They are widely used as raw materials in many areas such as agrochemical, perfume, pharmaceutical industries. They therefore have several physical, chemical and biological properties. In order to enlarge this family of compounds and elucidate almost all of its properties, researchers have developed various synthetic methods that are not very complex and less expensive. Thus, from 4-hydroxycoumarin we have synthesized a series of 3-acyl-4-hydroxycoumarins by C-acylation. This study is therefore dedicated to the reactivity of 3-acyl-4-hydroxycoumarins. The synthesized coumarins showed a high reaction potential based on the chemical functions present in their structures. To enhance them later, we can try to graft other functions which can be the subject of several transformations such as: condensation, functionalization, cyclization, acylation. So to access more interesting new poly-functionalized compounds both at the reactivity and biological level. These molecules (3-acyl-4-hydroxycoumarins) being new, very little information is known on their physicochemical behavior in writings. On the other hand, the reactivity of molecules with similar structures to those of acyl-hydroxycoumarins such as 4-acylisochroman-1,3-diones and 3-acetyl-4-hydroxycoumarin have been the subject of scientists’ work. It emerges from this study that 3-acyl-4-hydroxycoumarins shows strong chemical reactivity which can be used biologically.
Abstract: Coumarins are the most important oxygenated heterocyclic of natural compounds. They are widely used as raw materials in many areas such as agrochemical, perfume, pharmaceutical industries. They therefore have several physical, chemical and biological properties. In order to enlarge this family of compounds and elucidate almost all of its properties...
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