An Indian Journal Trade Science Inc. Volume 3 Issue 3 OCAIJ, 3(3), 2007 [104-106] September 2007 Solvent-free One-pot Synthesis Of Polyhydropyridopyrimidine Derivatives Via Hantzsch Condensation Using Sulphamic Acid Catalyst KEYWORDS Hantzsch condensation; Sulfamic acid; Polyhydropyridopyrimidine; Solvent-free. ABSTRACT An efficient Hantzsch condensation of polyhydropyridopyrimidine deriva- tives was reported via a four-component coupling reaction of aldehydes, bar- bituric acid, ethyl acetoacetate and ammonium acetate in the presence of H 2 NSO 3 H under solvent-free conditions. Operational simplicity, use of a re- usable, economically convenient catalyst under solvent-free condition is de- scribed in this paper.  2007 Trade Science Inc. -INDIA INTRODUCTION 4-Aryl 1,4-dihydropyridines(1,4-DHP s) are well known as calcium channel blockers and emerged as one of the most important classes of drugs for the treatment of cardiovascular classes, including hyper- tension [1] . 1,4-dihydropyridines possess a variety of biological activities, such as vasodilator, bronchodi- lator, anti-atherosclerotic, antitumor, geroprotective, hepatoprotective and antidiabetic agent [2a-d] . Recent studies have revealed that 1,4-DHP s exhibits sev- eral medicinal applications like neuroprotectant [3a] and platelet anti-aggregatory activity [3b] , in addition cerebral antischemic activity in the treatment of Alzheimer s disease [3c] and as chemo sensitizer in tu- mor therapy [3d] . These existing examples clearly dem- onstrate the remarkable potential of novel DHP de- rivatives as a source of valuable drug candidates. A Organic CHEMISTRY Organic CHEMISTRY recent computational analysis of the comprehensive medicinal chemistry database showed the DHP framework to among the most prolific chemo-type found. Development of drug resistance (intrinsic acquired), remains a clinical obstacle in the chemo- therapy in many cancers [4-5] . Among the possible re- sistance modifiers, the dihydropyridines, calcium antagonists, have been studied extensively as the analog of verapamil [6] . Literature reveals that 1,4- DHP derivatives combined with a single ring have been mostly reported. Thus the synthesis of the het- erocyclic nucleus is of continuing interest. In view of the importance of polyhydroquinolin derivatives, many classical methods for their synthe- sis were reported [7-12] using conventional heating and refluxing approaches in the presence of an organic solvent. These methods, however, involves long re- action times, harsh reaction conditions, the use of a Gopal Kakade, Balaji Madje, Madhav Ware, Ravi Balaskar, M.S.Shingare* Department of Chemistry, Dr.Babasaheb Ambedkar Marathwada University, Aurangabad-431004, (INDIA) Tell : +0091-240-2400431-37(Ext. 467) ; Fax : +91-240-2400291/490 E-mail : msshingare@yahoo.com Received: 25 th June, 2007 ; Accepted: 30 th June, 2007 Short Communication