Furanones halogenated

Fig. 11.1 Characteristic acyl homoserine lactones (AHLs) (a-c) are structurally similar to representative halogenated furanones (d-f) reported from Delisea pulchra (de Nys et al. 1993 Gould et al. 2006)...

Considering that the halogenated furanone type QS inhibitors (e.g. 28, see below) isolated from the red marine alga Delisea pulchra [68, 69] have substituents in the 3- and 4-positions, Olsen et al. [70] reported on the parallel synthesis of new AHL analogues in which the substituents were introduced into the 3- and 4-position of the lactone ring. 

The D. pulchra furanone compounds generally consist of a furan ring structure with a substituted alkyl chain at the C-3 position and a bromine substitution at the C-4 position (Fig. 5). The substituent at the C-5 position may vary in terms of side chain structure. The natural furanones are halogenated at various positions by bromine, iodine, or chlorine [128]. D. pulchra produces at least 30 different halogenated furanones which are stored in specialized vesicles and are released at the surface of the thallus at concentrations ranging from 1 to 100 ng/cm2 [132]. Field experiments have demonstrated that the surface concentration of furanones is inversely correlated with the degree of colonization by marine bacteria [133]. 

It is also interesting to note that the halogenated furanones were often stable in the distribution system and in simulated distribution system tests. Previous controlled laboratory studies had suggested that halogenated furanones, particularly MX, may not be stable in distribution systems. In at least five instances, MX levels actually increased in concentration from the plant effluent to the distribution system point sampled [11, 12]. Occasionally, MX levels decreased in the distribution system, but in these instances, it was still generally present at detectable levels. 

Konig GM, Wright AD, Bemardinelli G (1995) Determination of the Absolute Configuration of a Series of Halogenated Furanones from the Marine Alga Delisea pulchra. Helv Chim Acta 78 758... 

Manefield M, Welch M, Givskov M, Salmond GPC, Kjelleberg S (2001) Halogenated Furanones from the Red Alga, Delisea pulchra, Inhibit Carbapenem Antibiotic Synthesis and Exoenzyme Virulence Factor Production in the Phytopathogen Erivinia carotovora. FEMS Microbiol Lett 205 131... 

Pearce AN, Chia EW, Berridge, MV, Maas EW, Page MJ, Webb VL, Harper JL, Copp BR (2007) E/Z-Rubrolide O, an Anti-inflammatory Halogenated Furanone from the New Zealand Ascidian Synoicum n. sp. J Nat Prod 70 111... 

Hentzer M, Riedel K, Rasmussen TB, Heydom A, Andersen JB, Parsek MR, Rice SA, Eberl L, MoUn S, Hoiby N, et al. Inhibition of quorum sensing in Pseudomonas aeruginosa biotilm bacteria by a halogenated furanone compound. Microbiology 2002 148 87-102. 

Delisea pulchra (red algae) Halogenated furanones Antifouling... 

In vivo studies of QS disrupting compounds have included the use of halogenated furanones in black tiger prawns (P. monodon) (Manefield et al, 2000), Artemia (Defoirdt et al, 2006) and rotifers (Tinh et al, 2007) and the use of cinnamaldehyde and cinnamaldehyde analogues in Artemia... 

---