In the present work, catalytic activity of acidic as well as basic sites present over the microporous molecular sieves has been demonstrated. These acid-base sites display the combined catalytic reactivity in tap/deionized water for the efficient synthesis of poly functionalized pyridine derivatives. During this study, testing of various solvents revealed the suitability of tap water as a reaction medium, due to its highly polar nature, presence of alkali and alkaline earth metal ions in it and hydrophobic interactions between the surface of molecular sieves and organic molecules. Most importantly, unmodified microporous molecular sieves have been used for the first time in water for organic transformation. This synthetic strategy works under essentially neutral conditions by conventional as well as ultrasound method. (C) 2011 Elsevier B.V. All rights reserved.