Synthetic methods of 1H-pyrazolo[1,2-b]phthalazine Derivatives

Abstract:

This review deals with the synthetic methods of pyrazolo[1,2-b]phthalazine derivatives using one-pot multi-component reactions via modern and traditional methods. The synthetic methods are subdivided into groups according to the type of reactants e.g (1) one-pot three-component reaction of 2,3-dihydrophthalazine-1,4-dione, aldehydes and acetonitriles; (2) one-pot three-component reaction of 2,3-dihydrophthalazine-1,4-dione, aldehydes and aroyl acetonitriles; (3) one-pot three-component reaction of 2,3-dihydrophthalazine-1,4-dione, aldehydes and acetylacetone or 4-hydroxy-2H-chromen-2-one or acetylene derivatives; (4) one-pot four-component condensation reaction of phthalimide, hydrazine hydrate, aldehydes and acetonitriles; (5) one-pot four-component reaction of phthalic acid, hydrazine hydrate, indole-3- carbaldehyde and acetonitriles; and (6) one-pot three-component condensation reaction of 2,3- dihydrophthalazine-1,4-dione, aldehyde, and dimedone derivatives. Moreover, the various methods were reported.

Recent Trend in the Chemistry of Triazolopyrimidines and their Applications

:

This review deals with the synthetic methods, chemical reactions, and applications of triazolopyrimidine derivatives. The synthetic methods and chemical reactions are subdivided into groups according to the junction between triazole and pyrimidine moieties for instance [1,2,4]triazolo[1,5-a]pyrimidine, [1,2,4]triazolo[1,5-c]pyrimidine, [1,2,3]triazolo[1,5-a]pyrimidine, [1,2,3]triazolo[1,5-c]pyrimidine, [1,2,4]triazolo[4,3-c]pyrimidine, and [1,2,4]triazolo[4,3-a]pyrimidine. Pharmacological activity of triazolopyrimidins is also reported.

A convenient synthesis of novel amino acid derivatives with potential antibacterial activity using sustainable materials

Following the principles of green chemistry, cardanol derivatives have been used as renewable, low-cost and easily available natural starting materials to construct a variety of protected and unprotected amino acid derivatives. The reaction of cardanol derivatives with different phthalylamino acids including glycine, alanine, phenylalanine and valine in the presence of N,N′-dicyclohexylcarbodiimide (DCC) as coupling reagent yielded the target compounds in high yields. Deprotection of phthalylamino acid derivatives was achieved by heating with hydrazine hydrate. The chemical structures of all products were confirmed by spectral (FTIR, MS, 1H NMR, 13C NMR) and elemental analyses. The synthesised products were evaluated for their antibacterial activity, and the compounds exhibited potent to weak activity in comparison with a standard drug.

An efficient one-pot catalyzed synthesis of 2,5-disubstituted-1,3,4-oxadiazoles and evaluation of their antimicrobial activities

A facile and convenient one-pot catalyzed synthesis of 2,5-disubstituted-1,3,4-oxadiazole derivatives as efficient antimicrobial agents was described.

Synthesis of New Peptidyl- and Glycosylpyrimidine Derivatives

A new series of 2- N-(phthalyl- or tosylamino acid)pyrimidines have been synthesised from the coupling of pyrimidine derivatives with phthalyl- or tosylamino acids. Hydrazinolysis of 2- N-phthalyl derivatives afforded unprotected amino acid derivatives. New derivatives of peptidylpyrimidines have been synthesised from the reaction of pyrimidine derivatives with α-amino acids methyl ester hydrochloride viz different routes. Also, new glycosides have been prepared from the reaction of pyrimidine derivatives with α-D-glucopyranosyl bromide. Most of the synthesised compounds showed a significant antimicrobial activity.

Efficient Synthesis of Thieno[2,3-d]Pyrimidines and Related Fused Systems

The synthetic potency of readily accessible, ethyl 2-amino-4-methyl-5-(4-nitrophenoxy)thiophene-3-carboxylate (1) as a versatile precursor for the synthesis of novel polyfunctionally substituted thienopyrimidines is reported. The latter derivatives undergo further heterocyclisation to the related polycyclic fused systems via reactions with different reagents.

Facile three-component synthesis of dithiocarbamate derivatives with potent antimicrobial activity

A one-pot three-component synthesis of 3-oxo-3-(phenoxathiin-2-yl)-1-phenyl/(4-chlorophenyl)propyl alkyl/aryl-dithiocarbamate was achieved from the reaction of 3-phenyl/(4-chlorophenyl)-1-(phenoxathiin-2-yl)propenones, amine and carbon disulfide. The antimicrobial activities of some compounds were also screened against some selected bacteria and fungi.

An efficient one-pot, three-component synthesis of 5-hydrazinoalkylidene rhodanines from 1,2-diaza-1,3-dienes

A novel three-component synthesis of 5-hydrazinoalkylidene rhodanine derivatives starting from aliphatic primary amines, carbon disulfide, and 1,2-diaza-1,3-dienes is described. The reaction proceeds successfully under both solution and solid-phase conditions.