Sex hormones testosterone

The male sex hormone testosterone contains C, H, and O and has a mass of 288.2089 amu as determined by high-resolution mass spectrometry. What is the likely molecular formula of testosterone ... 

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. 

The chemical formula of a compound represents its composition in terms of chemical symbols. Subscripts show the numbers of atoms of each element present in the smallest unit that is representative of the compound. For molecular compounds, it is common to give the molecular formula, a chemical formula that shows how many atoms of each type of element are present in a single molecule of the compound. For instance, the molecular formula for water is H20 each molecule contains one O atom and two H atoms. The molecular formula for estrone, a female sex hormone, is Clgl-I2202, showing that a single molecule of estrone consists of 18 C atoms, 22 FI atoms, and 2 O atoms. A molecule of a male sex hormone, testosterone, differs by only a few atoms its molecular formula is (lyH2802. Think of the consequences of that tiny difference ... 

DHEA is an adrenal hormone that is a precursor to the sex hormones testosterone and estrogen, as well as other hormones. DHEA is reported to increase testosterone and decrease total body fat, and also to have anabolic and anti-aging effects. The... 

Androgens are male sex hormones testosterone and dihydrotestosterone are good examples ... 

This annulation process was of considerable value in early approaches to steroid synthesis. The structural relationship of the bicyclic product obtained here to the male sex hormone testosterone is immediately apparent. Further, the non-conjugated carbonyl is now activating the adjacent carbon that subsequently features in building up the third ring system. 

Testosterone (5.45) is the prototypic androgen sex hormone. Testosterone is synthesized by the testes, and must be reduced to dihydrotestosterone (5.46, DHT) before it will bind to the receptor. Among highly active synthetic testosterone analogs, 7a-methyl-19-nortestosterone (5.47) and oxandrolone (5.48) have about 100 times greater activity than testosterone as androgens. 17a-Methyltestosterone (5.49) is orally active. 

Steroids like cholesterol 335, cholic acid 336, or the sex hormone testosterone 337 play an important role in almost all living organisms. Therefore they are the... 

Two female sex hormones, estradiol-17 and progesterone, and one male sex hormone, testosterone, are used as growth promoters on beef cattle (Fig. 7.1). By nature, they are all endogenous products playing an important role in controlling reproductive functions in humans and animals. When applied exogenously they will enter the same metabolic pathways as the endogenously produced molecules. 

FIGURE 29-1 Pathways of adrenal steroid biosynthesis. Cholesterol is the precursor for the three steroid hormone pathways. Note the similarity between the structures of the primary mineralocorticoid (aldosterone), the primary glucocorticoid (cortisol), and the sex hormones (testosterone, estradiol). See text for further discussion. 

Other steroids include the sex hormones testosterone, progesterone, and the estrogen family (estrone, estradiol, estratriol, etc. Figure 12.30). 

A young adult male produces about 2.4 x 10-5 mol per day of the steroid sex hormone testosterone. The molecular mass of testosterone is 288. How many grams of testosterone per day does a young adult male produce ... 

If as above we simply represent alicyclic rings sharing two Gs by a vertical line, then we can represent the basic tetracyclic structure of lanosterol as G61G61 G6 C5 (noting that there are two double bonds and various alkyl substituents and also a 3-hydroxyl on the first of the alicyclic rings). Many subsequent reactions yield cholesterol, a major triterpene membrane component that modifies the fluidity of animal cell membranes and is a precursor for synthesis of animal bile acids (fat solubilizing amphipathic detergents) plant triterpenes and steroid hormones such as the corticosteroids cortisol and cortisone, the mineralocorticoid aldosterone and the sex hormones testosterone and 17-(3-oestradiol. The structure and bioactivity of the plant terpenes is sketched below. 

Though highly effective at reducing the risk of pregnancy, the birth control pill has been linked to such side effects as increased risk of heart attack and stroke. Anabolic steroids are generally synthetic versions of the male sex hormone testosterone and are used to promote the development of muscle mass and to enhance athletic performance. 

The first testicular hormone isolated was androsterone, a metabolite of testosterone. This also was achieved by Butenandt starting with an extract from 15,000 liters of urine supplied by Schering from which he obtained only 15 mg of pure crystals. Four years later, Laquer isolated 10 mg of the primary male sex hormone, testosterone, from 100 kg of steer testis. In all cases on this table the key to isolation was the quantitative bioassay as listed. 

Steroids are a naturally occurring family of organic molecules of biochemical and medical interest. A great deal of controversy has surrounded various steroids. We worry about the amount of cholesterol in the diet and the possible health effects. We are concerned about the use of anabolic steroids by athletes wishing to build muscle mass and improve their performance. However, members of this family of molecules derived from cholesterol have many important functions in the body. The bile salts that aid in the emulsification and digestion of lipids are steroid molecules, as are the sex hormones testosterone and estrone. 

Terpenoids are also used as chemical messengers. If the communication is between different parts of the same organism, the messenger is referred to as a hormone. Examples of hormones are shown in Figure 1.8. Giberellic acid is a hormone used by plants to control their rate of growth. Testosterone and oestrone are mammalian sex hormones. Testosterone is a male hormone and oestrone, a female. 

A sample of the male sex hormone testosterone, C19H28O2, contains 3.88 X 10 hydrogen atoms, (a) How many atoms of carbon does it contain (b) How many molecules of testosterone does it contain (c) How many moles of testosterone does it contain (d) What is the mass of this sample in grams ... 

Often, the enhancement is accomplished by the use of steroid compounds such as testosterone, the principal male sex hormone. Testosterone is responsible for the secondary sex changes that occur in males as they reach puberty. Testosterone is also produced by females, but only in amounts about 5% that of males. In both sexes, testosterone influences energy levels and protects the body from developing osteoporosis. 

Identify which sex hormones (testosterone, estrogens, or progesterone) are produced in ... 

Cholesterol is the biochemical precursor for both, the adrenocorticosteroid hormones cortexone and cortisol, and the sex hormones testosterone and oestradiol. Cholesterol is first hydroxylated at C-20 and C-22. The next tangible intermediate is pregnen-3)S-ol-20-one (Latin praegnatio pregnancy). After oxidation and a retro-acyloin reaction, the rest of the molecule is formally cleaved off as isocaproic aldehyde (4-methylpentanal). 

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