Cornutus

Fridericus Osannus (ed.), Lueius Annaeus Cornutus. De Xatura Decrrum (Gottingen, 1844), 159. 

The aggregation pheromone of the broad-horned flour beetle (Gnatocerus cornutus) was reported to be (lJR,4i, 5S)-(+)-acoradiene (33) by Tebayashi et al. [72]. Scheme 47 shows Mori s synthesis of (lRy4Ry5S)-33 [73]. The key-step was the ring-closing olefin metathesis of A to give B. An X-ray analysis of C confirmed the structure shown. The product (lJR,4JR,5S)-33, however, was different... 

Notropis cornutus 180 25% growth reduction after exposure for 7 days 51... 

While the pheromones of Tenebrio and Tribolium originate from a mixed biosynthesis, those produced by males of the broad horned flour beetle, Gnatho-cerus cornutus, represent true terpenes. Initially, the configuration of this new pheromone had been erroneously proposed to be (IR,4R,5S) a-acoradiene [325] however, independent syntheses of pure stereoisomers [326,327] proved the correct structure to show (lS,4A,5A)-configuration 165. The scope of the synthesis is shown by Mori (see chapter by Mori in volume 1 and [15]). A minor component of the G. cornutus was reported to be a-cedren-14-al 166 [328]. 

Ishikawa, M., Ishida, M., Shimakura, K., Nagashima, Y., and Shiomi, K. (1998c). Purification and IgE-binding properties of a major allergen in the gastropod Turbo cornutus. Biosci. Biotechnol. Biochem. 62,1337-1343. 

Juji, E., Takashima, H., Suko, M., Doi, M., Takaishi, T., Okudaira, H., Ito, K., and Miyamoto, T. (1990). A case of food-dependent exercise induced anaphylaxis possibly induced by shellfish Sulculus supertexta and Turbo cornutus). Arerugi 39,1515-1522. 

From the muscle of T. cornutus were isolated two phosphonoglycosphin-golipids, the major of which has the same structure as that of that isolated from visceral tissue the minor differs from it by the phosphate component, and has the structure of l-0- 6-0-[(2-aminoethyl)phosphono]-D-galacto-... 

From T. cornutus have also been isolated 2-(methylamino)ethylphos-phoric acid derivatives of di- and tri-galactosylceramides, wherein the substituted phosphoric acid group is located143,143a at 0-6 of the D-galactosyl terminal residue. 

Base treatment of helical biliverdins with 2-chloroethyl side chains leads to intramolecular rearrangement to yield derivatives with extended conformations <89JAI525>. This work has been extended to include inter alia the syntheses of Neobiliverdin Ixd (26), a natural product from the ovaries of the sea snake Turbo cornutus, by reaction of (25) with base <95T2243,2255>. 

There are other examples of volatile hydrocarbon pheromones in beetles that have been researched less extensively. One of these is from the broad-homed flour beetle, Gnatocerus cornutus (F.) (Coleoptera Tenebrionidae), a common stored-product pest. Tebayashi et al. (1998) found that males produce at least one compound that was attractive to both sexes in laboratory bioassays and at sub-nanogram levels. The compound was identified as the sesquiterpene (+)-acoradiene. The beetle-derived enantiomer was subsequently synthesized... 

The most widespread native species is the common or silver shiner Notropis cornutus), which is virtually ubiquitous in many surface waters east of the Mississippi in the United States and is also widespread in eastern Canada. This species is important as a forage fish, and as a baitfish. 

Among species which do have commercial value, the abalone, Haliotis gigantea, contains 23% protein, the wreath-shell. Turbo cornutus, 19% (Simidu et al., 1953). Both these species were from Japanese waters. 

In this case, the misassigned stereochemistry of the pheromone of G. cornutus caused a considerable problem for us, and the correct structure could be assigned finally by synthesis. 

Alginate lyase from Turbo cornutus acted on sodium alginate and resulted in a rapid decrease in viscosity and a gradual increase in reducing power of the substrate solution. The result of gel filtration of the reaction products indicated that uronic acid oligosaccharides were liberated as the final product. The fact that the enzyme attacked preferentially the D-mannuronate-rich moieties of the alginate molecule was demonstrated by an analysis with paper electrophoresis of the reaction products after acid treatment, which separated the uronic acid oligosaccharides from the uronic acid polysaccharides. 

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