Cinnathambi Subramani Maheswari, V. Tamilselvi, R. Ramesh
Jan 2, 2020
Citations
0
Influential Citations
9
Citations
Journal
Organic Preparations and Procedures International
Abstract
We now demonstrate a one-pot syntheses of the title compounds using 2-aminopyridine (2-AP) as a reusable organocatalyst. Generally, nitrogen and oxygen containing heterocyclic compounds perform crucial roles in the pharmaceutical and agricultural industries. Phthalazine bearing compounds with bridgehead nitrogen have significant pharmacological applications. In addition, their luminescence and fluorescence properties have been productively investigated. The synthesis of 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives via the three component cyclocondensation reaction of aromatic aldehydes, phthalhydrazide, malononitrile/ethyl cyanoacetate has been achieved by using various catalysts such as [Bmim]OH, PTSA/BmimBr, Et3N/EtOH, 11 NaHCO3, 12 nano-ZnO, NaBr, saccharin, Fe3O4, 16 CAN and PEG-SAC. The literature reports show their intrinsic advantages and disadvantages. Most of the reported protocols employed active cyanomethylene reagents, such as malononitrile and ethyl cyanoacetate, for the synthesis of 1H-pyrazolo[1,2-b]phthalazine-5,10-dione derivatives. Cyanoacetamide is one of the active methylene compounds which has been extensively used in heterocyclic synthesis. This motivated us to use it as the active methylene reagent for the preparation of 3-amino-1H-pyrazolo[1,2-b]phthalazine-2carboxamide derivatives. Similarly, the pyrazole templates have a broad range of medicinal applications. Indeed, some pyrazole-containing molecules, such as celecoxib, viagra and pyrazofurine, are blockbuster drugs of the pharmaceutical industries. The pyranopyrazole motifs are highly desirable heterocyclic compounds which exhibit significant biological activities such as antimicrobial, anti-inflammatory, anticancer, insecticidal and molluscicidal properties. In recent decades, the four component reaction of hydrazine hydrate, ethyl acetoacetate, malononitrile and aldehyde has been successful for the synthesis of pyranopyrazoles using different catalysts. 2-Amino-4H-benzo[g]chromene derivatives also show excellent biological activities. Hydroxy substituted naphthalene-1,4-dione derivatives are used as fluorescent