The objective of this work is the synthesis of new quinoline molecules which could have some biological activities. This chapter reported a new approach to the synthesis of some quinoline derivatives. The Baylis-Hillman reaction on 2-methoxy-3-formyl quinoléines derivatives have applied in order to obtain Baylis-Hillman adducts. The products are characterized by FTIR, NMR and X-ray single crystal diffraction .Also, a study of the antibacterial activity of the 3-(2-chloro quinoline)-3-hydroxy-2 methylene propanonitrile products synthesized have been explored. This assessment is made by using the disk diffusion method. The results showed that the 3-(2'-chloroquinoline)-3-hydroxy-2-methylenepropanonitril derivatives present a good antibacterial effectiveness against the strains tested Gram-positive and no antibacterial potency was observed against the stains Gram-negative used in the test.
TopIntroduction
Nature is the source of a large number of molecules with major interest for humans. This reservoir is extremely rich in new organic compounds, with a high level of structural diversity, but also; a significant therapeutic potential, motivates the search for efficient routes for their synthesis and that of the like.
The quinoline ring system is a common structural component of a wide variety of natural or synthetically prepared products with highly desirable biological activity (Michael, 1997). It is a heterocyclic scaffold of paramount importance to human race. Indeed, quinoline derivatives are some of the oldest compounds which have been utilized for the treatment of a variety of diseases.
The bark of Cinchona plant (also known as Jesuit’s or Cardinal’s bark) containing quinine was utilized to treat palpitations (Levy & Azoulay, 1994) fevers and tertians since more than 200 years ago. Quinoline, a diastereoisomer of quinine was in the early 20th century acknowledged as the most potent of the antiarrhythmic compounds isolated from the Cinchona plant (Wenckebach, K.F., 1923).
Compounds containing quinoline motif are most widely used as antimalarials (Lutz, 1946; Surrey, 1950; Bilker, 1989; Roma, 2000), antibacterials (Desai, 1996; Fang, 2000; Phan,, 2004), antifungals (Vargas et al., 2003), anti VIH (Wilson, 1992; Strekowski, 1991) and antitumor agents (Dassonneville, 2000; Bailly, 2000). They have antiseptic, antipyretic and antiperiodic properties (Khan, 2007). Substituted quinolines play also an important role as receptor antagonists of endothelin (Cheng, 1996), 5HT3 (Anzini et al., 1995), NK-3 (Giardina et al., 1997) and leucotriens (Gauthier et al., 1990). Those compounds are used as inhibitors of tyrosine kinase PDGFRTK (Maguire et al., 1994), (H+/K+)-ATPase (Ife et al., 1992), dihydrorotate deshydrogenase (Chen, 1990; Zeevi, 1993) and 5- lipoxygenase (Musser et al., 1987).
Additionally, quinoline derivatives find use in the synthesis of fungicides, virucides, biocides, alkaloids, rubber chemicals and flavoring agents (Holla et al., 2006). They are also used as polymers, catalysts, corrosion inhibitors, preservatives, and as solvent for resins and terpenes (Fishbein, 1979). Furthermore, these compounds find applications in chemistry of transition-metal catalyst for uniform polymerization and luminescence chemistry (Calus, 2007). Quinoline derivatives also act as antifoaming agent in refineries (Caeiro, 2007). Owing to such as significance, the synthesis of substituted quinolines has been a subject of great focus in organic chemistry.
One of the developed research lines in recent years is devoted to the synthesis of new quinoline derivatives from the 2-chloro-3-formyl quinoline derivatives. These are of great interest synthetic in the organic chemistry field.
We focus on 3-formyl quinoline derivatives substituted in position two; either chlorine or a methoxy as starting precursors. The work performed is divided into two stages: first, we describe the preparation of 3-formyl-substituted quinolines derivatives by two chlorine position. The second step, involves the substitution of chlorine by methoxyl. The aldehyde function in position 3 will allow us, for further processing selected, access to structurally diverse derivatives.
The study that we are undertaking, purpose the preparation and structural identification of original quinoline compounds that will be subsequently submitted to an assessment of antibacterial activity.
Our strategy is to apply the Baylis-Hillman reaction of some derivatives of 2-chloro-3-formyl quinoline to prepare a new series of Baylis-Hillman adducts derived. This reaction is a catalytic coupling of activated olefins and carbon electrophiles leading to classes of highly functionalized molecules. Among some Baylis-Hillman adducts, have interesting biological activities and are also an important reservoir of intermediate reaction precursors countless classes of compounds as useful as each other.
Given the phenomenon spread of the resistance and limited antibiotics in development number the discovery of new antibacterial agents, has become more indispensable. Joined in the general context, we will evaluate the antibacterial activated of some derivatives prepared.