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Synteza oraz aktywność antyfidantna laktonów

Mazur Marcelina

Wiadomości Chemiczne

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2023

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[Z] 77, 5-6

533--554

EN

Antifeedants, or food deterrents, are substances that, by acting on the sense of taste of insects, entirely or partially inhibit their feeding and can be used to reduce the population of harmful species. Antifeedants have the advantage of low toxicity and high selectivity towards selected groups of pests, providing an alternative to the classically used insecticides, which usually have a broad spectrum of action and greater toxicity, even towards vertebrates. Among their numerous activities, lactones can exhibit antifeedant properties. However, the use of natural lactones as antifeedants is limited due to their low isolation yields from natural sources and complex chemical synthesis. Therefore accesible synthetic compounds are of great interest. This work presents the synthesis pathways and the deterrent activities of the lactones obtained in convenient transformations, often from natural terpene precursors.

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Synteza i aktywność antyfidantna pochodnych farnezolu

Gliszczyńska A., Masłowiec D., Szczepanik M., Nawrot J., Wawrzeńczyk C.

Przemysł Chemiczny

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2011

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T. 90, nr 5

759-763

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Lactones 18. Synthesis of Bicyclic Lactones with Methyl-, Di- and Trimethyl Substituted Cyclohexane System

Grabarczyk M., Szumny A., Gładkowski W., Białoński A., Ciunik Z., Wawrzeńczyk C.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 11

1763-1771

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Naturalne i syntetyczne antyfidanty owadów : cz.2

Paruch E.

Wiadomości Chemiczne

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2001

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[Z] 55, 1-2

119-149

EN

Antifeedants, chemicals which prevent insects from feeding, have been at the centre of interest of researchers for the last forty years. Most of them are of natural origin., being a part of plant protective system. Antifeedants of followin groups: diterpenoids (including degraded limonoids), triterpenoids, alkaloids, lignanes, flavonoids, and coumarine derivatives are presented here. The most numerous group of diterpenoids are cleradanes, isolated mainly from plants of Teucrium genus. Clerodin, ajugarin and jodrellin are the best known members of this group. The second large group are limonoids, belonging to tetranortriterpenes, found mainly in plants of Meliaceae and Rutaceae family. The main compound of this group is azadirachtin, isolated from Azadirachta indica (Meliaceae). Not being harmful to mammals, it displays strong feedingdeterrent activity towards a great number of insect species. Huge amount of limonoids has beeb found in plants. Advanced studies on the synthesis and correlation between chemical structures and biological activity for clerodanes and limonoids have been carried out. Synthetic fragments of natural antifeedants, which exhibit activity comparable to the natural compounds, are also presented . Degraded limonoids are the natural and synthetic diterpenoid compounds, the structures of which are fragments of natural limonoids. Great interes has been taken in this group for the last 10 years. Some alkaloids are also presented here, as they are one of the first known insect antifeedants. They are active towards different insect species, including stored grain pests. The last presented group are coumarine derivatives, active against Spodoptera litura. In this case studies on structure-activity correlation were carried out as well . The perception of antifeedants at the sensory level may involve different mechanisms. Feeding deterrents may stimulate specialized receptors tuned to other compounds and thus alter the sensory code. There is also a hypothesis, based on electrophysiological data, that the impulses from different receptors are not received independently, but in a comlexed form. Modification of this neural code changes insect's behaviour. On the basis of biological data it has been postulated that polyphagous insets are less sensitive to antifeedants than more specialised species.

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Naturalne i syntetyczne antyfidanty owadów : cz.1.

Paruch E.

Wiadomości Chemiczne

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2001

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[Z] 55, 1-2

93-118

EN

Insect antifeedants are chemicals which inhibit feeding, but do not kill the insect directly, the insect often remaining near the antifeedant source and possibly dying through starvation. Many antifeedants have been found in plants, being a part of their protective system against its predators. Antifeedants, unlike pesticides, are often selectively toxic towards some insect species, whereas they are not harmful to the other ones and to mammals. As crop protection currently relies upon the use of broad spectrum of pesticides, friendlier to environment antifeedants are focus of recent research. Their current use is limited, as it is difficult to obtain them in useful quantities. Moreover, most of them are highly complexed molecules, which are not readily synthesised. The aim of researchers is to obtain a synthetic antifeedant of a simple structure, which retain the potency of natural products and fulfil synthetic requirements to be of practical use. The mono- and sesquiterpenoid natural and synthetic antifeedants are presented here. There are few natural monoterpenoid compounds of deterrent activity, whereas there are many numerous groups of sesquiterpene ones. The most known among sesquiterpenes are drimanes, isolated from bark of Drimys species, containing bicyclofarnesane skeleton - active antifeedants against aphids. The second large group are compounds isolated from mushrooms of Lactarius species, divided into marasmanes and lactaranes, active towards stored products pests. Many synthetic derivatives of natural antifeedants have been investigated so as to find correlation between structure and activity. Biological data showed that there is no single functional group responsible for deterrent activity. Even a small structure modification in different parts of a molecule may reduce the activity drastically. However, it is significant, that en-dialdehyde function, as well as g- or d-lactone ring are often present in active feeding deterrents. Sesquiterpene lactones, isolated from wide range of plants, are a very large group of insect antifeedants. Mono- and sesquiterpene lactones are the most promising compounds in search of new, synthetic insect antifeedants. Several synthetic terpenoid lactones of twelve carbon atoms, active deterrents against stored grain pests, are also presented.

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Lactones 5 : Synthesis of Some terpenoid Lactones from G,D-Epoxy Esters

Olejniczak T., Nawrot J., Ciunik Z., Wawrzeńczyk C.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 5

673-680

EN

D-Hydroxy-G-lactones and G-hydroxy-D-lactones were synthesized from acyclic isoprenoid G,D-epoxy esters in acid induced lactonization. The reaction course was depended on the acidic agent applied. The mechanism of lactonization is presented.