Synthesis, Crystal Structure, and Biological Activity of Diethyl-2-[5-(4-Fluorophenyl)-7-(Trifluoromethyl)Pyrazolo[1,5-a] Pyrimidine-3-Carboxamido]Pentanedioate

Trifluoromethyl-β-dicarbonyls as Versatile Synthons in Synthesis of Heterocycles

Trifluoromethyl group relishes a privileged position in the realm of medicinal chemistry because its incorporation into organic molecules often enhances the bioactivity by altering pharmacological profile of molecule. Trifluoromethyl-β-dicarbonyls have emerged as pivotal building blocks in synthetic organic chemistry due to their facile accessibility, stability and remarkable versatility. Owing to presence of nucleophilic and electrophilic sites, they offer multifunctional sites for the reaction. This review covers a meticulous exploration of their multifaceted role, encompassing an in-depth analysis of mechanism, extensive scope, limitations and wide-ranging applications in diverse organic synthesis, covering the literature from the 21st century. This comprehensive review encapsulates the applications of trifluoromethyl-β-dicarbonyls and their synthetic equivalents as precursors of complex and diverse heterocyclic scaffolds, fused heterocycles and spirocyclic compounds having medicinal and material importance. Their potent synthetic utility in cyclocondensation reactions with binucleophiles, cycloaddition reactions, C-C bond formations, asymmetric multicomponent reactions using classical/solvent-free/catalytic synthesis have been presented. Influence of unsymmetrical trifluoromethyl-β-diketones on regioselectivity of transformation is also reviewed. This review will benefit the synthetic and pharmaceutical communities to explore trifluoromethyl-β-dicarbonyls as trifluoromethyl building blocks for fabrication of heterocyclic scaffolds having implementation into drug discovery programs in the imminent future.

Synthesis, Crystal Structure and Antitumour Activity of Ethyl 2-[(2-Amino-3-Cyano-4-Phenethyl-4H-Naphtho[1,2-b]Pyran-8-yl)Oxy]acetate

Ethyl 2-[(2-amino-3-cyano-4-phenethyl-4 H-naphtho[1,2- b]pyran-8-yl)oxy]acetate has been synthesised by condensation of ethyl 2-chloroacetate with the hydroxy group of 2-amino-8-hydroxy-4-phenethyl-4 H-naphtho[1,2- b]pyran-3-carbonitrile. The latter was prepared from cinnamaldehyde, malononitrile and naphthalene-1,6-diol through Knoevenagel condensation and cyclisation reaction and then reduction with hydrogen in the presence of Pd/C at room temperature. The crystal structure of the title compound was determined. In addition, the compound showed distinct inhibition of the proliferation of some cancer cell lines.

Synthesis, Crystal Structure and Antitumour Activity of 3-Amino-N-(5-Fluoro-2-Methylphenyl)-4-Morpholino-1H-Indazole-1-Carboxamide

Compound 3-amino- N-(5-fluoro-2-methylphenyl)-4-morpholino-1 H-indazole-1-carboxamide has been synthesised by condensation of 4-fluoro-2-isocyanato-1-methylbenzene with 4-morpholino-1 H-indazol-3-amine, which was prepared from 2,6-difluorobenzonitrile by amination with morpholine and then cyclisation with hydrazine hydrate. The crystal structure of the title compound was determined. In addition, the compound inhibits proliferation of some cancer cell lines.

Synthesis, Crystal Structure, and Biological Activity of 3-Amino-4-Morpholino-N-[2-(Trifluoromethoxy)Phenyl]-1H-Indazole-1-Carboxamide

The title compound, 3-amino-4-morpholino- N-[2-(trifuoromethoxy)phenyl]-1 H-indazole-1-carboxamide has been synthesised by condensation of 1-isocyanato-2-(trifluoromethoxy)benzene with 4-morpholino-1 H-indazol-3-amine, which was prepared from 2,6-difluorobenzonitrile by amination with morpholine and then cyclisation with hydrazine hydrate. The crystal of the title compound belongs to the monoclinic system, space group P21/n with a = 11.0292(7) Å, b = 11.4332(8) Å, c = 15.6690(8) Å, α = 90°, β = 102.481(6)°, γ = 90°. In addition, the compound possesses distinct effective inhibition on the proliferation of cancer cell lines.

Synthesis of New Substituted 5-amino-8H-phthalazino[1,2-b]quinazolin-8-one Derivatives

A series of novel substituted 5-amino-8 H-phthalazino[1,2- b]quinazolin-8-one derivatives synthesised by condensation of different amines with 5-chloro-8 H-phthalazino[1,2- b]quinazolin-8-one, which was prepared from methyl 2-aminobenzoate by condensation with hydrazine hydrate and then cyclisation with a phthalic anhydride in N,N-dimethylacetamide at refluxing condition. The intermediate and target compounds were obtained in good yields and were easily purified by filtration or recrystallisation.

Synthesis of Several New 1-arylpyrazolo[3,4-d]Pyrimidines Containing an Amide Moiety

A series of novel 1-arylpyrazolo[3,4-d]pyrimidine derivatives, containing an amide moiety, was synthesised by condensation of different acids with 1-(2,4-dichlorophenyl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine. This intermediate was prepared from 5-amino-1-(2,4-dichlorophenyl)-1H-pyrazole-4-carbonitrile by condensation with triethyl orthoformate and then cyclisation with ammonium hydroxide solution in tetrahydrofuran at room temperature. In addition, the molecular structure of a 1-arylpyrazolo[3,4-d]pyrimidine containing an amide moiety was determined by single crystal X-ray diffraction.

Synthesis, Crystal Structure and bIological Activity of 5-(4-fluorophenyl)-N,N-dimethyl-7-(trifluoromethyl)Pyrazolo[1,5-a]Pyrimidine-3-carboxamide

The title compound, 5-(4-fluorophenyl)-N,N-dimethyl-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine-3-carboxamide, has been synthesised by condensation of dimethylamine with 5-(4-fluorophenyl)-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine-3-carboxylic acid. This intermediate was prepared from ethyl 5-amino-1H-pyrazole-4-carboxylate by cyclisation with 4,4,4-trifluoro-1-(4-fluorophenyl)butane-1,3-dione and then saponification with sodium hydroxide. The crystal structure of the title compound was determined. The compound possesses distinct effective inhibition on the proliferation of some cancer cell lines.