Steroids nomenclature rules

Implicit ia the base names are the absolute configurations at carbons 8 and 12 and the iadicated numbering systems. Derivatives of these parent stmctures are named according to terpene and steroid nomenclature rules (see Steroids Terpenoids). The lengthy and awkward nature of the chemical abstract systematic nomenclature (12) for these compounds has resulted ia the development (13) and use of simplified nomenclature based on common names. 

In agreement with the lUPAC Corrected Tentative Rules 7) for Steroid Nomenclature the Verairum alkaloids are classified in the jervanine (1), veratranine (2), cevanine (3), and solanidanine (4) groups. 

Details of the very specific steroid nomenclature must be taken from the original rule codex (Pure Appl. Chem. 1989, 61, 1783 see also l.c. on page 5). Here only the fundamental compound types and the most elementary rules can be considered. 

Nomenclature. The Vitamin D compounds ate steroidal materials and thus ate named according to the lUPAC-IUB rules for nomenclature (1) (Table 1). Vitamin [520-91 -2] is a mixture of vitamin D2 and lumisterol. 

Nomenclature of steroids. Revised tentative rules Biochemistry (1969) 8, 2227-2242 Amendments (1971) and corrections Biochemistry (1971) 10, 4994-4995... 

The IUPAC Definitive Rules for Nomenclature of Steroids15 contain proposals for naming steroid alkaloids and steroids containing fused... 

IUPAC Nomenclature of Organic Chemistry and IUPAC-IUB Biochemical Nomenclature, Definitive Rules for Nomenclature of Steroids, J. PureAppl. Chem. 31, 283(1972). 

International Union of Pure and Applied Chemistry, /. Am. Chem. Soc. 82, 5575-84 (I960) Definitive rules for the nomenclature of amino acids, steroids, vitamins, and carotenoids (lUPAC). 

The naturally occurring cardenolides and the functions and chemistry of insect moulting hormones have been reviewed. The synthesis of steroid phosphates, sulphates, and glycosides has been summarised in a new book which draws attention to inadequacies in the current Rules of Carbohydrate Nomenclature when two types of glycosidic linkages are present, and in which is proposed a modification of these rules applicable to steroid glycosides. 

Rules of nomenclature appear early on in many beginning organic chemistry texts. In somewhat the same vein, the Introduction to this book starts with the conventions for naming steroids. This is followed by a concise account of the molecular mechanism of action by which many steroids exert their biological effects. More detailed descriptions of the activity of these compounds will be found in the opening paragraphs of the individual stmctural classes. 

The lUPAC rules of lipid nomenclature have been developed to convey the maximum level of structural information within the name of the lipid. From this information, the reader should be able to reconstruct the component structure in a systematic fashion. For this reason, in most circumstances, the established system of systematic nomenclature should be encouraged rather than the use of trivial or common names. However, exceptions to this generality can be justified in the cases of steroids and carotenoids. In these cases, systematic nomenclature is often unwieldy for everyday usage and common names are well established in the respective fields. 

Reference lUPAC and lUB, Definitive Rules for Nomenclature of Steroids 7... 

International Union of Pure and Applied Chemistry, and International Union of Biochemistry. Definitive Rules for Nomenclature of Steroids . Pure Appl. Chem. 1972, 32, 285-322. Also published in Biochemistry 1969, 8, 2227-2242. 

Although many conventional names (e.g., cholesterol, cortisol, testosterone, etc.) are used in steroid molecules, the use of systematic names (based on lUPAC rules) is recommended. According to the nomenclature, a complete description of a steroid molecule should include the name of their parent compound (e.g., pregnane-21C, androstane-19C, or estrane-18C series) and the name, number, position, and orientation (a or jS) of all functional groups. 

The lUPAC-IUB revised tentative rules for nomenclature of steroids vere published. 77 17o... 

Butterworths, 1958) gives the full text of the lUPAC recommendations, containing definitive rules for hydrocarbons, fundamental heterocyclic systems and steroids, with tentative rules for nomenclature in the vitamin B12 field, and a corresponding volume Nomenclature of Inorganic Chemistry has been issued by the same publishers (1959). Nomenclature of biochemistry, inorganic and organic chemistry is also discussed in J. Amer. chem. Soc. 82, 5523-84 (1960). 

Two other nomenclature terms that have been used to store stereochemical information in connection tables are the labels aor b indicating whether a substituent points below or above a parent (ring) system, respectively. This method is frequently used for steroids. The actual structure can differ from the parent not only by additional substitution but also by, for example, ring contraction, which is coded as modifier to the parent. Stereoparent descriptors lack the generality of the CIP rules as a separate reference model has to be defined for each ring system. The prime benefit of this system is the ease with which the descriptor can be assigned by humans given a known reference template. 

The nomenclature used in this text is in agreement with the I UP AC commission on the Nomenclature of Organic Chemistiw and the lUPAC/IUB commission on Biochemical Nomenclature—Revistid tentative rules for nomenclature of steroids [Biochim. Biapkys. Acta 164, 453 (1968) Steroid Biockem. 1, 143 (1970)]. 

These symbols also correspond to the absolute configuration of the substituents. However, this nomenclature in its original form is not capable of describing the synthetic steroid compounds with which we must deal in performing a total synthesis. In actual fact, the existing rules of nomenclature are suitable for denoting only one optically active form, and for antipodes or racemates it is necessary to have recourse to excessively complex names. This can be explained by the following examples. 

Natural progesterone, A -pregnene-3,20-dione, has the structure expressed by formula (296). Its antipode (297, 298) must be named by the existing rules of nomenclature as "8a, 9)8,10j3,13a, 14jS,17Q -A -pregnene-3,20-dione. This name is not only difficult to understand but it is completely unsuitable for use since no name is left for the racemic compound it can be described only by a combination of the names of the two enantiomers. Consequently, it is natural that with the development of work on the total synthesis of steroids much attention has been devoted to the question of nomenclature. 

Steroids covered by definitive rules issued jointly by the Commissions on the Nomenclature of Organic and Biological Chemistry with the lUPAC 1957 rulesThey revise the earlier tentative version and differ chiefly in reducing the principal nomenclature to four parents to be used always with 5a- or 5p-. They cover also specialized uses of nor and seco which are useful also in other fields. A further revision and expansion has been released for publication.4(W... 

Heterocyclic steroid analogues are treated according to the rules of replacement nomenclature (see p. 51). 

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