Scent glands beaver

Benzoic acid in the free state, or in the form of simple derivatives such as salts, esters, and amides, is widely distributed in nature. Gum benzoin (from styrax ben in) may contain as much as 20% benzoic acid in the free state or in combinations easily broken up by heating. Acaroid resin (from anthorrhoca haslilis) contains from 4.5 to 7%. Smaller amounts of the free acid are found in natural products including the scent glands of the beaver, the bark of the black cherry tree, cranberries, pmnes, ripe cloves, and oil of anise seed. Pern and Tolu balsams contain benzyl benzoate the latter contains free benzoic acid as well. The urine of herbivorous animals contains a small proportion of the glycine derivative of benzoic acid, hippuric acid [495-69-2] (CgH CONHCH2COOH). So-called natural benzoic acid is not known to be available as an item of commerce. 

The scent glands of the North American beaver. Castor canadensis, contain the alkaloid castoramine which has been shown to be a hydroxy derivative of desoxynupharidine and is convertible into the latter (41). The hydroxyl is hydrogen-bonded to the nitrogen and this gave the first... 

Furyl)-8-methyloctahydroindolizine (12) has been isolated from the scent-gland of the Canadian beaver Castor fiber L.), together with (-)-castoramine and a series of related quinolizidines and other alkaloids. The alkaloid (12) is only a minor... 

The previous review on Nuphar (water-lily) alkaloids in this treatise appeared in Volume 35, and covered the period 1974-1987 (7). It overlapped in part with the treatment of simple bicyclic Nuphar metabolites in Volume 28 (7). Nuphar alkaloids include sesquiterpenoid monomeric (C15) piperidine and quinolizidine alkaloids as well as more complex dimeric (C30) sulfur-containing metabolites. Related metabolites isolated from the scent glands of the Canadian beaver, Castor fiber, also include a unique indolizidine alkaloid 944 606). Only the indolizidine and simple quinolizidine alkaloids are relevant to the present review. Compounds mentioned in the ensuing discussion are illustrated in Fig. 18. 

The chemistry shown in Eq. (21) uses a / -amino selenide as a radical precursor. /S-Amido radical cyclizations in which y -amido selenides served as the radical precursors have also been reported. One example has been described within the context of an approach to the ABC-ring system of manzamine A [47]. Another appears in an efficient synthesis of indolizidine 72, a component of castoreum derived from the Canadian beaver scent gland (Eq. 22) [48]. It is notable that allylic strain plays a role in the latter free-radical cyclization, as the furyl residue undoubtedly occupies an axial site on the incipient tetrahydropiperidone ring. 

Lederer, E. 1946. Chemistry and biochemistry of the scent glands of the beaver Castor fiber). Nature, 157, 231-232. 

The original structure of (— )-deoxynupharidine (15) was not correct and much of the earlier literature concerning these alkaloids contains erroneous structures. The compound has a l/ ,4/f,7/f,9a/ configuration, as indicated in Fig. 36.4 (Howard and Michael, 1986). Similar alkaloids have been isolated from the scent glands of the Canadian beaver. Castor fiber (Fig. 36.4). The oil of this gland or castoreum is used as a fixative in the perfumery industry. (— )-Deoxynu-pharidine (15) is one of the components of the complex mixture of compounds found in this oil. Although it is not clear. 

Beavers are large pale brown to chestnut-brown rodents. The Canadian beaver inhabits lakes and rivers of Canada and northern United States, while the Siberian beaver is found in Europe and Siberia. Castoreum is the secretion accumulated in glands located near the pubis (between anus and sex organs) of these animals. These scent glands with their secretion (castoreum) are collected and dried, from which extracts (absolute, tincture etc.) are prepared by solvent extraction. Canadian castoreum is considered superior in quality to the Siberian castoreum. ... 

Related C15 quinolizidines and one indolizidine alkaloid have also been found in the exudate from the scent glands of the Canadian beaver Castor fiber) (castoreum, previously used as a fixative in perfumery). For convenience, these animal alkaloids wiU be included in the present discussion. 

Recently, Rosell and Sundsdal [78] tentatively identified 21 of the 43 constituents present in 96 scent marks deposited directly on snow or ice mounds by the Eurasian beaver, C. fiber. In this study, a higher final oven temperature was employed and several steroids were eluted from the capillary column. Because the main focus of this study was to determine whether the beaver uses castoreum and/or anal gland secretion for scent marking and not the full chem-... 

The anal gland secretion of beaver, C. canadensis, differs between the sexes (Gr0nneberg, 1978-79). The male grey duiker, Sylvicapra grimmia, has more 2-heptanone and 2-nonadecanone in its preorbital secretion than the female. Two thiazoles (2-isobutyl-1,3-thiazole and 2-isobutyl-4,5-dihydro-l,3-thiazole) and an epoxy ketone (3,4-epoxy-2-dodecanone) are also more abundant in the male s secretion. Correlated with these chemical differences is the fact that only males scent mark with the preorbital gland (Burger etal., 1990). 

Mountain beaver, Aplodontia rufa, a primitive rodent from northwestern North America, fed less from food bowls if the rim was scented with mink anal gland secretion, or urine from mink, bobcat, coyote, or dog. The control odors butyric acid or guinea pig urine had no effect (Epple et fl/., 1993). Mountain beaver did not respond significantly to mustelid sulfur compounds though, yet these deter other small mammals (Epple etal, 1993). 

Castoreum or caster is a strongly scented creamy fluid derived from the genitals of male beavers. This name is also applied to similar materials taken from otters and muskrats. These fluids are used by the animals to mark their territories and to attract females. They are reputed to have the same effects on other species, notably humans, when incorporated into perfumes or creams. Castoreum perfume is produced by placing the entire gland into alcohol. 

Beavers live in family units that are usually composed of a mated pair, yearlings, and kits. They occupy and defend territories (Schulte, 1993). Beavers rely heavily on chemical signals for social interaction and recognition. They use anal gland secretion (AGS) and castoreum to communicate many types of information, including family membership, kinship, sex, individuality, and territoriality (Svendsen, 1980 Sun and Miiller-Schwarze, 1997 Schulte, 1998). To do these, they build scent mounds on the bank, within 2 meters from the water, in areas of high activity around their territory, and then apply castoreum and/or AGS to the top (Svendsen, 1978, 1980 Rosell and Nolet, 1997 Rosell and Sundsdal, 2001). 

The total number of observation nights was 162 (castoreum 78 anal gland secretion 84). Beavers responded (any kind of alteration to the experimental scent mounds) to male castoreum in 31 % of the cases, and to female castoreum in 26 %. The difference was not significant = 0.205, d.f. = 1, P > 0.50). Nor did we find that beavers showed any difference in response to male and female anal gland secretion samples (male 46% female 39%, = 0.347, d.f. = 1, P > 0.50). To examine any likely subtle differences in... 

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