Synthesis, Characterization and Biological Evaluation of Some New Oxino bis-Pyrazole Derivatives

Pyrazoles are very important class of biologically active compounds and many of their derivatives are in clinical use. Pyrazole derivatives have been shown to exhibit antihyperglycemic [1], hypoglycemic [2] and fungicidal properties [3]. Some of them are also used as insecticides and herbicides [4,5]. Of the condensed pyrazoles, specially pyrano[2,3-c]pyrazole is a fused heterocycle comprising of pyrazole and pyran rings which are known as the sub-structural units of several biologically active compounds [6,7]. While structurally similar polyfunctionalized benzopyrans have been widely used as intermediates due to their biological and pharmacological properties such as antibacterial, molluscicidal, anthelminitic, hypnotic and insecticidal activity [8-14]. Some 2-amino-4Hpyrans are used as photoactive materials [15] where as the 4H-pyran ring is also a structural unit of a number of natural products [16-18].