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•Pyrrolotriazines are isosteres of nucleobases used to synthesize C-nucleosides.•Pyrrolo1,3,5triazines are not well described.•A scalable synthesis of 6-carboxylated ...1,3,5pyrrolotriazines was developed.•A regioselective halogenation of pyrrolotriazines was demonstrated.
Pyrrolotriazines and related fused azaheterocycles have high potential for the synthesis of bioactive compounds, especially as a purine base isoster in carbon linked nucleosides. Although many structurally related compounds have already been synthesized and used in medicinal chemistry, pyrrolo1,3,5triazines have barely been described. The present work describes the synthesis of such heterocycles via condensation of 2-amino-3-ethoxycarbonylpyrrole with ethoxycarbonyliso(thio)cyanate. In a brief reactivity study of the obtained fused pyrroles, O- and S-alkylation, ester hydrolysis as well as regioselective bromination at the 6-position was demonstrated.
A helpful manufactured course to the one-pot green synthesis of 2-amino-4H-chromenes through a tandem Knoevenagel-Michael cyclocondensation reaction of aldehydes, malononitrile, and resorcinol in ...polyethylene glycol (PEG-400) as accessible and biodegradable media have been detailed. All responses are completed in a brief time and the items are gotten in fabulous yields. The striking highlights of this eco-friendly approach are biodegradable media, fabulous yields, simple work-up without requires for column chromatographic separation, and no poisonous organic solvents, evasion of harmful reagents, one-pot strategy, and effortlessness of operation. Additionally, PEG-400 is exceedingly steady and can be reused for four sequential runs without major basic changes or misfortune of movement, which has been exceptionally advantageous in tending to natural concerns.
•Green synthesis of 2-amino-4H-chromenes.•Polyethylene glycol (PEG-400) as a recyclable and biodegradable reaction medium.•Simple work-up without the requiring for column chromatographic separation.
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•Carbonic anhydrase isoforms differ in their catalytic activity and efficiency.•Current CAIs show undesired side effects due to non-selectivity issue.•New CAIs have been designed in ...an attempt to identify CA selective compounds.•Three approaches have been proposed for the synthesis of these derivatives.
Carbonic anhydrases are ubiquitous, and their role in the hydration of carbon dioxide is essential for the survival of many tissues and organs. However, their association with many pathological diseases, especially in glaucoma, Alzheimer's, obesity, epilepsy, and tumorigenesis, has prompted the design and synthesis of novel carbonic anhydrase inhibitors (CAIs). Herein we describe (1) approaches used in the design of CAIs and (2) synthesis of small molecules as CAIs within the last five years. Despite the active research in this area, there are still more avenues to explore, especially selective inhibition of CA I, CA IX, and XII. These isoforms would continue to open up a diversity of carbonic anhydrase inhibitors containing 1,2,3-triazoles, imidazolone, pyrrolidone, thiadiazole, isatin, and glycoconjugates as part of their molecular frameworks.
The transition metal-catalyzed reaction of 2H-azirines with 1,2,4-tricarbonyl compounds leads to 3-(1,2-dioxoethyl)- and 2,3-dicarbonyl-pyrrole derivatives, useful building blocks for the preparation ...of 3-heterocyclyl pyrroles and pyrroles fused with heterocycles. The influence of catalysts and the reaction conditions on the yields of pyrroles and the regioselectivity of the reaction were studied. Experimental and theoretical results suggest that the reaction proceeds via the formation of an intermediate azirine–metal complex and subsequent nucleophilic N–C3 bond cleavage.
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Two series of functionalized imidazothiazolotriazine derivatives were synthesized via the condensation of imidazo4,5-
e
-1,2,4-triazine-3-thiones with acetylenedicarboxylic acid dimethyl and diethyl ...esters (DMAD and DEAD) and subsequent base-catalyzed rearrangement of the obtained imidazo4,5-
e
thiazolo3,2-
b
-1,2,4-triazines into regioisomeric imidazo4,5-
e
thiazolo2,3-
c
-1,2,4-triazine derivatives.
A facile, mild and efficient procedure for the synthesis of fully substituted pyrazolo3,4-bpyridin-5-amines is reported. A mixture of an α-azidochalcone, a 5-aminopyrazole and t-BuOK was stirred in ...DMF at ambient temperature for 5 min to afford the corresponding pyrazolo3,4-bpyridin-5-amines in good to excellent yields.
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O6; Oxidative cyclocondensation of o-aminobenzamide with various aldehydes in water using I2/KI as catalyst and oxidizing agent is carded out giving the corresponding quinazolin-4(3H)-ones 3a-n in ...good to excellent yields.
Acetylation of 2-amino-4-(4-methoxyphenyl)-6-oxo-1,6-dihydropyrimidine-5-carbonitrile (2) using acetic anhydride afforded N-pyrimidinylacetamide derivative 3 which upon formylation using ...Vilsmeier-Haack reagent produced β-chloroenaldehyde derivative 4. The chemical behavior of compound 4 was investigated toward some primary amines as well as heterocyclic amines yielding the corresponding Schiff bases. Compound 4 is used as a building block for the construction of nitrogen heterocyclic compounds such as pyrazoles, pyrimidines, pyridopyrimidine and diazepine through its reaction with a diversity of bifunctional nucleophiles such as hydrazines, guanidines, 6-aminouracil and ethylenediamine. The biological activity of the synthesized compounds was investigated. Structures of the newly synthesized products were deduced on the basis of their analytical and spectral data.
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