A novel Approach for the Synthesis of Spiroacenaphthelyne Pyrano- Pyrazole Derivatives

Multicomponent reactions (MCRs) have recently emerged as valuable tools in the preparation of structurally diverse chemical libraries of spiro heterocyclic compounds. Spiro compounds are an important class of naturally occurring material characterized by highly significant biological properties.[1] 4H-pyrans derivatives have been considered because of their pharmacological activity like include spasmolytic, diuretic, anticoagulant, anticancer, and antianaphylactil anticancer, cytotoxic, anti-HIV, anti-inflammatory, antimalarial, antimicrobial, antihyperglycemic and anti-neurodegenerative disorders like Alzheimer‘s, Parkinson‘s, and Huntington‘s disease.[2,3] We have developed the synthesis of spiroacenaphthylene in the reaction between acenaphthoquinone, pyrazolones and activated methylene compounds (like malononitrile derivatives) without using of catalyst in ethanol or water under mild reaction conditions. The structures of products were deduced from their IR, 1H NMR, and 13C NMR spectra. The mass spectra of these products displayed molecular ion peaks at the appropriate m/z values. The present procedure has the advantage that not only the reaction is performed under neutral conditions but also the reactants can be mixed without any activation or modification. The simplicity of the present procedure makes it an interesting alternative to complex multistep approaches.