Synthesis and biological evaluation of highly functionalized dispiro heterocycles

Abstract

A series of highly functionalized dispiro[3H-indole-3,2′-pyrrolidine-3′,3′′-piperidine]-2(1H),4′′-dione derivatives have been synthesized in good to excellent yields by one pot three-component 1,3-dipolar cycloaddition reaction of substituted isatin, sarcosine and 1-methyl-3,5-bis[(E)-arylidene]piperidin-4-one with high degree of chemo-, regio- and stereoselectivity. The structure and relative stereochemistry of cycloadducts were confirmed by single crystal X-ray diffraction as well as with the help of ¹H, and ¹³C NMR spectroscopic techniques. All the synthesized compounds were subjected to in vitro antimicrobial activity against various bacteria and fungi using broth microdilution method and antitubercular activity was carried out against Mycobacterium tuberculosis H₃₇Rv strain using Lowenstein–Jensen medium. Some of the compounds emerged as good antimicrobials and reasonable antituberculars compared to standard drugs.