Prostaglandin pheromones

In fish reproduction, the best-investigated pheromone system is that of the goldfish [Carassius auratus). Here, sex steroids and prostaglandins play important roles. The female produces two pheromones sequentially a preovulatory primer pheromone and a postovulatory prostaglandin pheromone that act on the male. 

The special potential for constructing double bonds stereoselectively, often necessary in natural material syntheses, makes the Wittig reaction a valuable alternative compared to partial hydrogenation of acetylenes. It is used in the synthesis of carotenoids, fragrance and aroma compounds, terpenes, steroides, hormones, prostaglandins, pheromones, fatty acid derivatives, plant substances, and a variety of other olefinic naturally occurring compounds. Because of the considerable volume of this topic we would like to consider only selected paths of the synthesis of natural compounds in the following sections and to restrict it to reactions of phosphoranes (ylides) only. 

Sorensen P.W., Hara T.J., Stacey N.E. and Goetz F. (1988). F-prostaglandins function as potent olfactory stimulants that comprise the post-ovulatory female sex pheromone in goldfish. Biol Reprod 39, 1039-1050. 

The optically active propargylic and allylic alcohols thus obtained are important synthetic intermediates in the enantioselective synthesis of insect pheromones, prostaglandins, prostacyclins, and many other bioactive compounds (Scheme 6-26).53... 

Other examples include the synthesis of California Red Scale Pheromone [80], prostaglandin PGF2a [81], House Mouse Pheromone [63], and Jasmon-ates [82]. 

FIGURE 7.1 Female goldfish pheromones, (a) The preovulatory pheromone 17a, 20/3-dihydroxypregn-4-en-3 one (b) the postovulatory pheromone 15-keto-prostaglandin 2 -... 

Other examples of messengers of biodiversity are shown in Table 12.4. However, observations as to the defensive role of metabolites are often circumstantial. Thus, tetrodotoxin, long thought to be a defensive compound in a tropical fish, Fugu niphobles, has recently been found to play a pheromonal role in the fish (Table 12.4). Similar conclusions have been drawn for prostaglandins in fish (Matsumura 1995). 

ORGANOBORANE. A compound composed of an unsaturated organic group and a borane obtained by the hydroboration reaction. Such compounds are useful catalytic reagents in organic syntheses of some complexity, e,g, cis- or (/awf-olefins, optically pure alcohols, alkanes, and ketones. Prostaglandins and insect pheromones have been synthesized by tlus means. A particularly versatile example is triphenylboron B(CgHsty. See also Borane Carborane and Hydroboration. 

Lactones and the macrocyclic lactones, like the y- and 5-lactones, are of importance since these ring systems are found widespread in nature. The simpler substituted lactones are important building blocks in the synthesis of many natural products, e.g. in the fields of antibiotics, anticancer pharmaceuticals, pheromones and prostaglandins to name but a few. 

Sorensen, P. W. and Goetz, F. W., Pheromonal function of prostaglandin metabolites in teleost fish, J. Lipid Mediators, 6, 386, 1993. 

L-Kynurenine (6) is a known oxidative metabolite of L-tryptophan. This study for the first time appears to represent this amino acid metabolite that has been identified as a pheromone in a vertebrate. Although additional minor constituents present in the active fraction were identified (.V-formylkynurenine, tyrosine, cystathionine, and prostaglandin F2a), none was observed to synergize the sex pheromonal activity of L-kynurenine (6). 

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