Cantharidine

Cannabinol, A -3,4-trans-tetrahydro-biological activity, 3, 877 Cannabinol, (—)-A -3,4- ran5-tetrahydro-as pharmaceutical, 1, 151 Cannabinolic acid synthesis, 3, 721 Cannabinolic acid, tetrahydro-photochemistry, 3, 721 Cannabis, citrylidene-, 3, 675 Cantharidin synthesis, 1, 440 Capillarin occurrence, 3, 677 ozonolysis, 3, 681... 

Canadian Plastics Industry Association (CPIA), 259 Canadian Pollution Prevention Information Clearinghouse (CPPIC), 281, 301 CANOPY , metribuzin, 34 Cantharidin, 34 Caprolactam, 34 Captafol, 34 Captan, 35... 

Singlet oxygen adds to cyclic 1,3-dienes to afford 1,4-endoperoxides 609). This type of reaction has first been applied successfully to the synthesis of ascaridole from a-terpinene 610) (6.4) and of the vesicatory compound cantharidine 6U) (6.5) some 25 years ago. 

Specimens of the pollen-feeding staphylinid beetle Eusphalerum minutum were found in cantharidin traps, which indicates that they are canthariphilous [121]. In addition, they contain small amounts of cantharidin 48, which is accompanied by palasonin 49. Palasonin has been previously only known from seeds and fruits of the Indian shrub Butea frondosa (Leguminaceae [122]). 

Defensive Compounds. Clerid beetles such as Trichodes apiarius were found to contain considerable amounts of cantharidin 48, accompanied by small to minute amounts of palasonin 49 [ 122,265]. Previously, the latter has been known only from seeds and fruits of the Indian shrub, Butea frondosa (Leguminaceae). It is suggested that these predatory beetles feed on cantharidin producing oede-merid and meloid beetles, see below. Several clerid species are canthariphilous [266,267],... 

Defensive Compounds. All developmental stages of oedemerid beetles contain and produce cantharidin as a defensive substance. The total amount of the terpenoid anhydride increases in successive instars [306]. Moreover, by using deuterium-labelled cantharidin it was found that males of Oedemerafemorata transfer no or only very small amounts of cantharidin 48 to females during copulation. False blister beetles cause a severe dermatitis, i.e. blisters with burning and itching sensation a few hours after contact with oedemerid haemo-lymph [307]. 

Defensive Compounds. Apart from cantharidin 48 and palasonin 49 the corresponding non-toxic imides cantharidinimide 159 and palasoninimide 160 could be identified in various bodyparts of the meloid beetle, Hycleus lunata [310,311]. 

While the Indian shrub Butea frondosa, contains (S)-(-)-palasonin of high enantiomeric purity, palasonin from Hycleus lunata shows a low ee with the (J )-(+)-enantiomer (20-50 ee) prevailing. Despite this difference between the insect-derived and the plant-produced product, an uptake of palasonin from hitherto unknown plant sources in the environment of Hycleus appears to be highly unlikely, however, palasonin may be produced by oxidative demethyla-tion of cantharidin [122]. 

The cantharidin titres of male and female specimens of Epicauta occidental, dead and live beetles as well as specimens stored under different conditions, were measured in detail [312]. 

Several predation tests especially with spiders and blister beetles [121,313, 314], show that spiders exhibit a wide range of sensitivities to meloid beetles as prey. In the racoon Procyon lotor it was shown that they quickly form an aversion to blister beetle prey, which is induced by cantharidin [314]. 

Many anthicid species are known to be canthariphilous [121]. After take up, males store the toxin in the accessory glands and transfer it as a kind of nuptial gift to the females. Many male anthicid species are characterized by ely tral exocrine glands which serve for excretion of cantharidin depending on the cantharidin titre. Similar to Pyrochroidae (see there) females test the cantharidin load of males before copulation and select those males which previously were able to incorporate this precious defensive compound from exogenous sources. 

Dettner K (1997) Inter- and intraspecific transfer of toxic insect compound cantharidin. Ecol Stud 130 115, Springer, Berlin Heidelberg New York... 

Palasonin (97), a cantharidin-related toxin, has recently been detected in the hemolymph and tissues of several families of beetles (Meloidae, Cleridae, Staphylinidae) that produce cantharidin or feed on cantharidin containing an-... 

Although many insect defensive compounds are endowed with diverse biological activities, few of them have been studied in depth to evaluate their potential pharmacological activities. Cantharidin (98) (Fig. 16),pederin (104) (Fig. 18), and some of the alkaloids isolated from ants (e.g., the solenopsins 109 and 110, Fig. 19) have been the subject of most of the investigations. These topics have been reviewed several times [111, 214,215], and we will only summarize here the most recent data. 

Endothall is a structural analogue of cantharidin (Fig. 20). Its mode of action is apparently inhibition of protein phosphatase(s). A struc-ture/activity relationship study demonstrated that the presence of the oxygen bridge and the location of the two carboxylic groups play important roles in the activity of the molecules. The unusual 7-oxabicyclo[2.2.1]heptane ring of endothal is similar to that of cinmethylin, another natural product-like herbicide for which the mode of action has also eluded scientists for many years. 

Matsuzawa M, Graziano MJ, Casida JE, Endothal and cantharidin analogues Relation of structure to herbicidal activity and mammalian tawsity, J Agric Food Chem 35 823-829, 1987. 

Cantharidin is a toxin isolated from fish. Among its numerous biological activities, cantharidin exhibits insecticide and herbicide properties. Cantharidin and norcanthar-idin are inhibitors of serine and threonine phosphatases, which are important enzymes for the regulation of cell processes and cell proliferation. Mono- and difluoronor-... 

Salicylic acid, propylene glycol, podophyllum resin podofilox, urea, cantharidin, fluorouracil, benzoic acid... 

Cantharidin is the active irritant isolated from cantharides. It is mainly used in the treatment of molluscum contagiosum and verruca vulgaris, particularly periungual warts. 

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