Musks, polycyclic chemical structures

Table 18. Chemical name, trade name, CAS number, chemical structure, molecular formula, molecular mass, n-octanol/water partition coefficient (log measured and/or predicted bioconcentration factors on a wet weight basis (BCFw) and on a lipid basis (BCFl) in mussel or fish, and occurrence of Polycyclic Musk Fragrances (PMFs) in aquatic environment and/or human milk and adipose tissue...

So far, the occurrence of seven polycyclic musks has been reported. Their chemical names, chemical structures and molecular formulae are described elsewhere (Rimkus, 1999). The structural feature of all polycyclic musks is an indane or tetraline skeleton, which is highly substituted mainly by methyl groups (Fig. 1). 7-Acetyl-l,l,3,4,4,6-hexamethyl-l,2,3,4-tetrahydronaphthalene (AHTN, trade name Tonalide) and 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzo-pyrane (HHCB, trade name Galaxolide) are the most abundant ones. In this study, also 4-acetyl-1,1 -dimethyl-6-fert-butylindane (ADBI, trade name Celestolide) and 6-acetyl-l,l,2,3,3,5-hexamethylindane (AHMI, AHDI, trade name Phantolide) are investigated (Fig. 1). Important physicochemical properties of these compounds, which determine their environmental distribution and transport (e.g. solubility), are presented in chapter 4.1.1, in Ricking et al. (2003) as well as in Simonich et al. (2000). 

Fig. 1 Chemical structures of the investigated polycyclic musks HHCB (C18H260), AHTN (C18H260), ADBI (C17H240) and AHMI (C17H240).

On the other hand, the term musk also refers to other compounds, with totally different chemical structure but possessing musk-Uke odor properties. These are commonly named synthetic musks and appeared as a response to ecrniomical and ethical motives. Artificial musks have been generally divided in three subgroups nitro musks, polycyclic musks, and macrocycUc musks. 

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