30-Androsterone

Whatever the physiology of odor perception may be, the sense of smell is keener than that of taste (22). If flavors are classed into odors and tastes as is common practice in science, it can be calculated that there are probably more than 10 possible sensations of odor and only a few, perhaps five, sensations of taste (13,21,35—37). Just as a hereditary or genetic factor may cause taste variations between individuals toward phenylthiourea, a similar factor may be in operation with odor. The odor of the steroid androsterone, found in many foods and human sweat, may eflcit different responses from different individuals. Some are very sensitive to it and find it unpleasant. To others, who are less sensitive to it, it has a musk or sandalwood-like smell. Approximately 50% of the adults tested cannot detect any odor even at extremely high concentrations. It is befleved that this abiUty is genetically determined (38). 

A direct, one-step aromatization of 19-substituted steroids has appeared in the Hterature, ie, cholesterol (3), dehydroisoandrosterone, androsterone, progesterone (1), and testosterone react with an electrophilic mthenium complex, C Ru , where Cp represents Tj -cyclopentadienyl, obtained through protonation of [Cp Ru(OCH2)]2 using triflic acid, to provide estrone (20) directly (46). 

Sex Hormones Testosterone and androsterone are the two most important male sex hormones, or androgens. Androgens are responsible for the development of male secondary sex characteristics during puberty and for promoting tissue and muscle growth. Both are synthesized in the testes from cholesterol. Androstenedione is another minor hormone that has received particular attention because of its use by prominent athletes. 

Steroids, e.g. cholesterol, triolein, androsterone sugars, e.g. fructose, glucose, ribose amino acids, pyrimidines, purines, alkaloids 110-150°C, 2-12 h Conversion to fluorescent derivatives by heating. [5]... 

Oxosteroids (17-ketosteroids) [1, 2] e.g. dihydroxyandrosterone, androsterone, aetiocholanolone, 11-oxoandrosterone... 

One of the very few examples of a practical application of a transition-metal catalyst in total synthesis is shown in Scheme 20.22 [107]. The chloroiridic acid catalyst (HjIrCfs) (6) reduces 71 to androsterone (72) by selective attack of the sterically less hindered ketone in the 3-position of 71. 

A series of conjugated polyenes capped with chromophores and containing an androstane spacer were synthesized by Wittig or Wittig-type olefinations from epi-androsterone 5150. For example, vinyl carboxaldehyde 52, prepared from 51 in 60% yield as shown in equation 32, was treated with 9-anthrylmethylphosphonium bromide and n-butyllithium to give diene 53. Exocyclic diene 53 was subsequently oxidized to vinyl carboxaldehyde 54. The androsterone vinyl aldehyde intermediate could either be treated with a tetraphenylporphyrinpolyenyl phosphonium ylide, or, as shown below, the phosphonium salt of the androsterone (55) could be reacted with TPP polyeneal 56. The desired all-(E) isomer, 57, was obtained from the ( )/(Z)-isomeric mixture by chromatographic purification. 

Recent results indicate that the air-borne steroids 5a-androst-2-en-17p-ol and 5a-androst-2-en-17-one, which are present in the urine of female E. maximus during the luteal phase at levels that are increased 10- to 20-fold, could be responsible for the synchronization of estrus in females living in close social relationships [117]. The ketone has previously been identified as a product of the incubation of androsterone sulfate with human axillary bacterial isolates [118]. 

In a study in which individual urinary components were determined and repeated samples from the same individuals analyzed, Dobriner and co-workers23 found that the androsterone excretion in twenty normal males 21 to 76 years of age varied from 0.2 to 7.0 mg. per day, a 35-fold range. Age was a factor in contributing to the wideness of this range, since older individuals tended to excrete less, but each individual s androsterone excretion was distinctive, and large differences which were truly inter-individual were observed. One man of 72 excreted, for example, more than twice as much as one who was 21 years old. This study will be referred to further in a later discussion (p. 101). 

Steckelbroeck S, Watzka M, Lutjohann D, Makiola P, Nassen A, et al. 2002. Characterization of the dehydroepi-androsterone (DHEA) metabolism via oxysterol 7alpha-hydroxylase and 17-ketosteroid reductase activity in the human brain. J Neurochem 83 713-726. 

The first androgen to be isolated in pure form was androsterone, in 1931, by the chemist Adolph Butenandt, the same guy who isolated the first pheromone (that for the female silkworm moth, bombykol), which we met back in chapter 6. Butenandt managed to isolate 50 mg (less than 0.002 ounces) of androsterone from 25,000 liters of men s urine Some efforts are more heroic than others. 

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