General Papers ARKIVOC 2008 (xii) 188-194 Synthesis and structure elucidation of hydrazones derived from N-(2,4-dimethylphenyl)-3-oxobutanamide Murat Çağlar Hamzaçebi, Sevim Rollas,* Ş. Güniz Küçükgüzel, and Bedia Koçyiğit Kaymakçıoğlu Marmara University, Faculty of Pharmacy, Department of Pharmaceutical Chemistry, Tibbiye cad. No: 49, 34668 Haydarpasa, Istanbul, Turkey. E-mail: sevim@sevimrollas.com Abstract Diazonium salts derived from amines 1 (sulfanilic acid, 4-nitroaniline, 4-aminosalicylic acid, sulfanilamide, sulfamethoxazole, sulfathiazole, sulfapyridine, sulfamerazine) were coupled with N-(2,4-dimethylphenyl)-3-oxobutanamide (2) resulting in the formation of hydrazones 3a–h. Keywords: Azo coupling, hydrazones Introduction Coupling products of diazonium salts with aliphatic active hydrogen compounds are widely used as intermediates for the synthesis of a large number of heterocyclic compounds. Pyrazoles, 1,2 isoxazolone, 3 2-pyrazoline-5-one 4,5 can be obtained by cyclization of coupling products with substituted hydrazine or hydroxylamine, respectively (Scheme 1). Both hydrazones 5,6-9 and their cyclization compounds 2–4 possess important biological and pharmacological properties. ArNH 2 NaNO 2, HCl 0–5 °C ArN≡N Cl – + H 2 C O R' O X N ArN O R' O X O N N R' O ArN H H N N N R' O ArN H R" N N N R' R N R" Ar H 2 NOH•HCl, NaOAc X = OR R"NHNH 2 X = OR R"NHNH 2 X = R Scheme 1. General synthetic routes for the formation of azo compounds and hydrazones. ISSN 1551-7012 Page 188 © ARKAT USA, Inc.