Available online www.jocpr.com Journal of Chemical and Pharmaceutical Research, 2012, 4(1):326-332 Research Article ISSN : 0975-7384 CODEN(USA) : JCPRC5 326 Synthesis and insecticidal activity of some nicotinic acid derivatives Madhukar B. Deshmukh, Sangram H. Patil and Chetan S. Shripanavar* Department of Agrochemicals and Pest Management, Shivaji University, Kolhapur, Maharashtra, India _____________________________________________________________________________________________ ABSTRACT Nicotinic acid containing pyridine nucleus having side chain at third position gives the significant effect on toxicity to the insects. Therefore, we have reported the synthesis of some nicotinic acid derivatives and their insecticidal activities. The strategy employed for the synthesis of desired nicotinic acid derivatives involved esterification of nicotinic acid. The methyl nicotinate get derivatise by 2-Fluorophenyl urea, 3-trifluoro methylphenyl urea, DL-nor- leucine, 2, 4-dichlorophenoxy acetic acid hydrazone and diethyl malonate which are further reacted with thiourea to get corresponding condensed product (1a-e). Further methyl nicotinate react with hydrazine hydrate to form nicotinoyl hydrazine (2). This when condensed with substituted aryl aldehydes gave the corresponding arylidene derivatives (3a -e). The structures of these synthesized compounds are confirmed on the basis of IR, PMR and Mass spectral analysis. Most of them showed the promising activity against Green peach aphid, Myzus persicae (Sulzer), American bollworm, Helicoverpa armigera (Hubner) and stored grain pest, Maize weevil, Sitophiles zeamais (Motschulsky). Keywords: Nicotinic acid, Esterification, Insecticidal activity. _____________________________________________________________________________________________ INTRODUCTION Nicotine is one of the oldest known plant origin insecticides, which possesses the remarkable insecticidal activity. Nicotine kills the insects rapidly within an hour causing the intensive tremors, convulsions and then paralysis. As early as 1746, the insecticidal activity of crude extract of tobacco leaves was used to control the insects. Metcalf has reported that 1.2 million pound of free nicotine was used in Agriculture in USA during 1944. Nicotine represents the class of “nicotinoids” with a unique mechanism of action. Nicotine mimics nAch and some of the nAchR types, has a direct interaction with the nAchR has been demonstrated and reported earlier. [1] Merger work has been done to co-relate the chemical structure with biological activity of nicotine and related compounds in mammals. However, much less attention has been devoted by their effects on insects. Therefore, the mechanism of action of nicotine and its derivatives is not primarily connected with anti-acetylcholine esterase activity. Detailed requirements by Yamamoto, lead to understand the structure activity relationship. Altering the position of side chain at the pyridine ring and the chain length between the 3-pyridyl and basic nitrogen had significant effect on toxicity. The secondary and tertiary amines were found to have insecticidal potency. Due to the high basicity of the second nitrogen in compare with pyridine nitrogen, the pyrrolidine or related nitrogen becomes protonated in a physiological medium at pH 7, in insect body. In this way, the molecule acquires the active form, which is able to compete with Ach on the receptor protein. With this view, nicotine or structurally related compounds are pre- insecticides enable to penetrate easily in to the body and the nervous tissue to the site of action. The protonation converts this pre-insecticide to the active form with the quaternary nitrogen, which is essential for the binding of the molecule to the anion site of the receptor. [2] Yamamoto, have reported the detail investigations on the structure