The present invention provides use of the compounds represented by formula (1): wherein, R1, R2, R3 and R4 are as defined in the specification, in all their stereo isomeric and tautomeric forms and mixtures thereof in all ratios, and their pharmaceutically acceptable salts, pharmaceutically acceptable solvates, pharmaceutically acceptable polymorphs and prodrugs and pharmaceutical compositions containing them for treatment of inflammatory disorders mediated by one or more cytokines selected from Tumor Necrosis Factor-alpha (TNF-α), interferon-γ (IFN-γ) and interleukins such as IL-1β, IL-2, IL-6, and IL-8. The present invention also relates to a pharmaceutical composition adapted for use in the treatment of inflammatory disorders. The present invention further provides a method of treatment of inflammatory disorders by administering a therapeutically effective amount of the said compound of formula (1) or its pharmaceutical composition, to a mammal in need thereof.