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Synthesis 2007(19): 3051-3055  
DOI: 10.1055/s-2007-990774
PAPER
© Georg Thieme Verlag Stuttgart · New York

Synthesis of 1-Oxo-1-(3-pyridazinyl) Derivatives - Potent Inhibitors of Fatty Acid Amide Hydrolase (FAAH): An Improved and Optimized Procedure

Goffredo Rosini*a, Daniele G. Andreottib, Primiano D’Ambrosioa, Emanuela Marottaa, Alessandro Tinarellia, Paolo Righia
a Dipartimento di Chimica Organica ‘A. Mangini’ - Alma Mater Studiorum, Università di Bologna, Viale del Risorgimento 4, 40136 Bologna, Italy
Fax: +39(051)2093654; e-Mail: goffredo.rosini@unibo.it;
b GlaxoSmithKline, Medicine Research Centre, Via A. Fleming 4, 37135 Verona, Italy
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Publication History

Received 18 May 2007
Publication Date:
11 September 2007 (online)

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Abstract

A greatly improved procedure for the preparation of long-chain α-ketopyridazines, a class of potent inhibitors of fatty acid amide hydrolase (FAAH), is described. This optimization study shows a great dependence of the yields of desired products on the pyrididazinyl lithium/Weinreb amide ratio and offers a general approach to this kind of compound.

Key words

3-acylpyridazines - regioselective acylations - FAAH inhibitors - Weinreb amides - lithiation - drugs

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