Sperm attractant

Sirenin is the sperm attractant produced by the female gametes of the water mold, Allomyces. Its synthesis has been accomplished by the use of an internal [2 + 1] cycloaddition step. 

Machlis L, Hill GGC, Steinback KE, Reed W (1974) Some characteristics of the sperm attractant from Oedogonium cardiacum. J Phycol 10 199-204 Maier I (1982) New aspects of pheromone-triggered spermatozoid release in Laminaria digitata (Phaeophyta). Protoplasma 113 137-142... 

Sirenin, a sperm attractant produced by female gametes of the phycomycete Allomyces... 

Muller, D.G., Gassmann, G., Boland, W., Mamer, F., and Jaenicke, L., Dictyota dichotoma (Phaeo-phyceae) identihcation of the sperm attractant, Science, 212, 1040, 1981. 

The intramolecular version of this reaction is more reliable, and has often been used to make compounds containing multiply substituted cyclopropanes. Corey made use of it in a synthesis of sirenin, the sperm-attractant of a female water mould. 

Sperm are attracted by chemical substances, which are released by eggs. This process is called chemotaxis and is a well-known phenomenon in most animals and lower plants.4 The attraction of sperm to eggs should counteract the effects of dilution and increase the probability of fertilization in free-swimming invertebrates. Since the fertilization rate may be low under natural conditions, the presence of such chemoattractants is believed to be important. Sperm-attractant substances have been identified in several marine invertebrates, including hydrozoans, mollusks, ascidians, starfish, sea urchins, and urochordates. 

A comparison of the structure of synthetic and natural compounds confirmed that the stereochemistry of SAAF was (3R, 4R, 7R, 25S)-3,4,7,26-tetrahydroxycholestane-3,26-di sulfate. The synthetic pure sample was also used to confirm that a single compound possesses both sperm-activation and sperm-attraction properties. Synthetic SAAF (30) activated C. intestinalis sperm at 3.7 nmol I 1 and concurrently exhibited attracting activity at a concentration less than 10 nmol l-1. 

More recently, an abalone sperm attractant has been identified. Sperm of the red abalone Haliotis rufescens responds to soluble factors released into the seawater by conspecific eggs. Bioassay-guided purification revealed... 

Corey et al. treated an allylic bromide with the THP-protected lithium propynol in their synthesis of ( )-sirenin, a sperm attractant of the water mold Allomyces, and the same reaction was also used in a synthesis of ( )-sesquicarene (Scheme 41). In addition, Meyers and Bienz used an alkyne alkylation (22) (23) to prepare the final intermediate for radical cyclization in their synthesis of the unnatural (-I-) isomer of the sesquiterpene, A 02). apnellene (24 Scheme 42). 

Miller, R.D. and Vogt, R. (1996). An N-terminal partial sequence of the 13kDa Pycnopodia helianthoides sperm chemoattractant startrak possesses sperm-attracting activity. y. Exp. Biol. 199, 311-318. 

Serrano, H., Canchola, E. and Garcia-Suarez, M.D. (2001). Sperm-attracting activity in follicular fluid associated to an 8.6 kDa protein. Biochem. Biophys. Res. Commun. 283, 782-784. 

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