Phenolic steroids, acidity

Kober reaction of phenolic steroids with strong acids leading to polymethyne ( [18, 19],... 

The ECD has seen its greatest utilization in the field of pesticide analysis. Chemicals such as dieldrin, aldrin and DDT are amenable to the ECD. In addition, the environmental hazards of polychlorinated biphenyls (PCBs) have been raised as a result of analyses by the ECD. Organometallics are also good electron absorbers. With the aid of halogen derivatization, many classes of organic compounds such as steroids, acids, amines, phenols, and alkenes have been assayed. 

A substantial improvement in the synthesis of steroid /3-D-glucosid-uronic acid derivatives was achieved by Conrow and Bernstein,125 who introduced cadmium carbonate as a new and effective catalyst in the Koenigs-Knorr reaction procedure its use proved to be particularly convenient in the synthesis of such derivatives of phenolic steroids, where the yields obtained by using silver carbonate had not usually exceeded 10%. Thus, by employing cadmium carbonate, several succesful syntheses in the series of phenolic steroids have been claimed (see, for example, Ref. 126). 

Methylation is a common feature of the metabolism of phenols and A-heterocyclic compounds. Thus, phenolic steroids, adrenaline, and some other catecholamines undergo O-methylation, while pyridine, nicotinic acid, and normorphine undergo N-methylation. The reaction occurs under the influence of 5-adenosylmethionine and a non-specific methyl transf erase. 

SBSE can be successfully used in the analysis of environmental samples [93-97] and for food analysis [98, 99]. PDMS is the most commonly used polymer, primarily because of its thermal stability and durability. SBSE has been modified by application of derivatization with different reagents (acetic anhydride, BSTFA, etc) [100-104]. This approach is suitable for the extraction of compounds requiring derivatization. The use of multistep derivatization with several extraction elements (each reaction is performed on a different stir bar) allows efficient extraction, desorption, and chromatographic analysis of compounds with different functional groups (e.g., phenols, steroids, amines, thiazoles, ketones). Acetic anhydride (ester formation), ethyl chloroformate (reaction of acids and amines), tetraethyloborane, and sodium bis-trimethylotrifluoroacetamide have been used for extraction and simultaneous derivatization [105]. 

Conrow and Bernstein63 recommended the use of cadmium carbonate instead of silver salts to prepare glucosiduronic acids of phenolic steroids. The yields are usually better than those obtained by use of silver salts. Rohle and Breuer64 also used cadmium carbonate in the synthesis of a glucosiduronic acid of estra-l,3,5(10)-trien-2,3,17/3-triol 17-monoacetate, which is oxidizable with silver salts. Thus, methyl tri-O-acetyl-a-D-glucopyranosyluronate bromide (27), on reaction with estrone (28) afforded 3-0-(methyl 2,3,4-tri-O-acety 1 -/3-D-glucopy-ranosyluronate)estrone (29). 

A few analytical methods have been selected as being of particular interest to organic chemists. The spectrophotometric determination of oxo-steroids as their glyoxalyl derivatives is mentioned on p. 331. The Kober reaction and its modifications,in which a phenolic steroid is heated with moderately concentrated sulphuric acid to generate chromogenic materials, is still not fully understood. Oestradiol 3-methyl ether, with 78 % sulphuric acid, gives a mixture including isomers of the 17-methyl-18-nor structure (776), and the derivative (777) with an... 

Over 300 pages of constants, conditions and data More than 1.000 refartncas Applicationt include alcohols and phenols, carboxylic acids, amines and hydroxyammas. ammo acids and danv-ativas. amides and ureas, carbohydrates, steroids and miscellaneous compounds... 

The formation of 2-methoxyestrogens from the estrogens requires also 2-hydroxylation of the phenolic steroids. It has recently been shown by Fishman et al. (1960a) that this reaction does in fact occur in human tissues. Following the injection of estradiol-l7 9-i5-C into a 22-year-old man, 2-hydroxyestrone was isolated from the urine. The extent of 2-hydroxylation appears to be considerable about 12% of the administered radioactivity was recovered from the urine as radioactive 2-hydroxyestrone. An extensive study on 2-hydroxylation of estriol by rat liver in vitro was carried out by King (1961 a,b). It was found that the 2-hydroxylase activity is limited to the microsomal fraction and requires either NADHj or NADPHz, and possibly a folic acid derivative ATP appears to stimulate the 2-hydroxylase. 

According to present knowledge, excretion of the biologically active phenolic steroids is made possible by conjugation, that is, by chemical combination with glucuronic acid or sulfuric acid. Steroids combined with these acids are more soluble in water and can be eliminated through the kidney. 

Digital glycosides, nucleosides, pesticides, pharmaceuticals, phospholipids, steroids DNA adducts, DNA and RNA fragments, dyes for food, inorganic ions, steroids Amines, amino acids, inorganic ions, peptides, purine and pyrimidine derivatives Amines, amino acids, indole derivatives, ohgopeptides, polyamines, sulfonamides Barbiturates, carboxylic acid esters, fatty acid derivatives, nitrophenols, polychlorobiphenyls (PCBs), peptides, pesticides, phenols, steroids, surfactants, triazines... 

Yanillin-siilphiirie acid for higher alcohols, phenols, steroids and essential oils. 

In this section the thin-layer chromatographic properties of phenolic compounds as revealed by their / /Values are given. The first part covers essentially the substituted derivatives of monocyclic phenols, the second part is concerned with phenolic acids (with their derivatives), and the final one with more complex phenolic compounds such as phenolic glycosides, flavonoids, anthocyanins, lignan derivatives, phenolic steroids, cannabinoids, and other types. Some overlap between subsections is inevitable, but this feature serves incidentally to interrelate the thin-layer chromatographic properties of phenolic compounds as a whole. The material in the last section has been dealt with in other monographs (1), and more emphasis has been placed in this review on substituted phenols and phenolic acids and their simple derivatives. 

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