Trail marking pheromone

The carbometallation of alkynes is also unique in its stereochemical pattern, since it is executed as an exclusive cis addition. For example, the stereoisomeric purity of pheromone 104, prepared as shown, is higher than 99.9% This feature is of special importance in the synthesis of natural pheromones, as the biological activity of these compounds is dramatically affected by the presence of an even negligible amount (less than 0.5% ) of the undesirable stereoisomer. Not surprisingly, this reaction has found numerous areas of application, especially in the stereospecific synthesis of the tri- and tetrasubstituted alkenes, a goal difficult to achieve by other methods. To illustrate the effectiveness of this approach, the synthesis of faranal 105, the trail-marking pheromone of the ant species Monomoriumpharaonis, is shown in Scheme 2.33. 

Aggregation Pheromones Trail-Marking Pheromones Alarm Pheromones Synomones Allelopathy... 

Antifeedant Compounds Insecticidal and Nematicidal Activity Diterpenes with Juvenile Hormone Activity Diterpenes That Prevent Reproduction in Insects Trail-Marking Pheromones Diterpenes from Marine Plants Sweeteners Medicinal Properties Antitumor Compounds Sesterterpenes Biosynthesis Biological Activity References... 

Cembrene derivatives also are found in some termites of the genus Nasutitermes, where they may play a role as trail-marking pheromones (Nahrstedt, 1982). 

Many different functions of pheromones have been found since Butenandt. Aggregation pheromones attract both sexes to a special location, while sex pheromones are offered by one sex only to attract or arouse the other one. Trail pheromones used by ants mark food trails and alarm pheromones change the state of alertness of conspecifics. These are only some of the functions pheromones can have, and similar different functions can be found in allelochemicals as well. 

Several long-range attractant sex pheromones have been identified (Table 3) or evidence for such a pheromone has been obtained in the past 13 years. The parasitoid Ascogaster reticulatus produces (9Z)-hexadec-9-enal 9 in a tibial gland [47]. The pheromone is spread by the females much like a trail on the substrate, and the males follow the mark to the source by close antennal contact with the substrate [48]. EAG studies have revealed that the males respond much more strongly to (9Z)-hexadec-9-enal than the females and that the response to the... 

Trail markers are used almost exclusively by social insects, such as bees, ants, and termites. An insect that has located a new source of food returns to the nest, marking his trail by releasing these substmices. At the nest, recraitment is initiated by perception of these trail pheromones. Some representative trail pheromones are presented in Fig. 17c. 

Wilson (3) and Wilson and Bossert (4) divided pheromones into release pheromones (if the stimulus triggers an immediate behavioral response in the receiving organism) and primer pheromones (if the response is a long lasting one). Substances involved in alarm, territorial marking, trail, social status, sexual attraction and reproductive isolation are release pheromones while the odors involved in puberty acceleration, pregnancy block, estrus synchronization or suppression are primer pheromones. 

Z J )-3,6,8-dodecatrien-l-ol (Z -DTE) has been shown to be the trailfollowing pheromone used by many termite species (8,9.10) including C. formosanus (11,12). This pheromone is produced in the sternal gland, which is located on the 5" abdominal stemite. Workers lay a trail of this chemical from a food source back to the rest of the colony to recruit workers and mark the path to the food source. 

Many insects emit minute quantities of chemicals called pheromones to send messages to other individuals of the same species. Some pheromones warn of danger, while others call for defense, mark a trail, or attract the opposite sex. During the past 40 years, the structures of many pheromones have been chemically determined. One of... 

Methylpyrrole-2-carboxylic acid (compound B) is the trail pheromone of the ant species Atta texana. A third of a milligram has been estimated to be sufficient to mark a path around Earth, and each ant carries only 3.3 ng (10 g). Propose a s3mthesis starting from 3-methylcyclobutene-1-carboxyUc acid (conqtound A). (Hint What dione is the retros3mthetic precursor to compound B, and how can you make it from compound A )... 

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