Steroid analogs, synthetic

CoCp(CO)2 also is a versatile synthetic precursor, which reacts with a wide variety of organic compounds. It serves as a source of the reactive CoCp unit, and this species catalyzes cyclization of alkynes as well. This reaction has been applied to the one step synthesis of steroid analogs [22]. 

Limitations of space preclude an exhaustive treatment of synthetic methods, and we therefore summarize only the most useful methods for directly introducing stable diazo and azido groups. Many of the reactions by which diazo groups are introduced have been described in detail for steroid analogs. ... 

In the early 1930 s, when the prime research aim was the commercial synthesis of the sex hormones (whose structures had just been elucidated), the principal raw material available was cholesterol extracted from the spinal cord or brain of cattle or from sheep wool grease. This sterol (as its 3-acetate 5,6-dibromide) was subjected to a rather drastic chromic acid oxidation, which produced a variety of acidic, ketonic and hydroxylated products derived mainly by attack on the alkyl side-chain. The principal ketonic material, 3j -hydroxyandrost-5-en-17-one, was obtained in yields of only about 7% another useful ketone, 3 -hydroxypregn-5-en-20-one (pregnenolone) was obtained in much lower yield. The chief acidic product was 3j -hydroxy-androst-5-ene-17j -carboxylic acid. All three of these materials were then further converted by various chemical transformations into steroid hormones and synthetic analogs ... 

Schimmer, B.P. and Parker, K.L., Adrenocorticotropic hormone adrenocortical steroids and their synthetic analogs inhibitors of the synthesis and actions of adrenocortical hormones, in Goodman and Gilman s The Pharmacological Basis of Therapeutics, 9th ed., Hardman, J.G. and Limbird, L.E., Eds., McGraw-Hill, New York, 1996, chap. 59. 

It seems worthy to comment on the name second generation lazaroid. Fooking at the structure of U-83836E, one may wonder why this compound is associated with 12-amino steroids at all, whereas it is just another model of a-tocopherol and should be compared not with first generation lazaroids but with the synthetic analogs of vitamin E (see above). 

Retinoids are a family of naturally occurring and synthetic analogues of vitamin A. The skin of subjects deficient in vitamin A becomes hyperplastic and keratotic (phrynoderma, or toad skin). While natural vitamin A is occasionally employed therapeutically, synthetic retinoids are more effective and represent a major advance in dermatological pharmacotherapy. Retinoids have myriad effects on cellular differentiation and proliferation it is likely that nuclear retinoic acid receptors mediate these effects by activating gene expression in a manner analogous to receptors for steroid hormones and thyroid hormones. Despite a common mechanism of action, however, retinoids vary widely in their physiological effects. 

Schimmer BP, Parker KL. Adrenocorticotropic hormone adrenocortical steroids and their synthetic analogs inhibitors of the synthesis and actions of adrenocortical hormones. In Brunton LL, et al, eds. 

Athletes engaging in androgen abuse usually obtain these drugs from various illicit but readily available sources.155 Some examples of anabolic steroids that are used by athletes are listed in Table 30-2. These agents include testosterone, synthetic analogs of testosterone, and precursors that are converted to ana-... 

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