Sterols relationships

Adolf Windaus Germany sterols relationship with vitamins... 

The path from squalene (114) to the corresponding oxide and thence to lanosterol [79-63-0] (126), C qH qO, cholesterol [57-88-5] (127), and cycloartenol [469-38-5] (128) (Fig. 6) has been demonstrated in nonphotosynthetic organisms. It has not yet been demonstrated that there is an obligatory path paralleling the one known for generation of plant sterols despite the obvious stmctural relationships of, for example, cycloartenol (128), C qH qO, to cyclobuxine-D (129), C25H42N2O. The latter, obtained from the leaves of Buxus sempervirens E., has apparentiy found use medicinally for many disorders, from skin and venereal diseases to treatment of malaria and tuberculosis. In addition to cyclobuxine-D [2241-90-9] (129) from the Buxaceae, steroidal alkaloids are also found in the Solanaceae, Apocynaceae, and LiUaceae. 

In an inciteful discussion of insect-microbe relationships, Jones (10) postulated that insect-microbial associations, known to involve catabolic (e.g. cellulose-degrading) and anabolic (e.g. biosynthesis of vitamins, sterols, and amino acids) processes necessary to the survival of the host, could also include detoxification abilities. Most investigations in this area have been limited (11). Nevertheless, some studies indicate detoxification of terpenoids (12,... 

According to the type of block Y, the correlation can be used for different problems. The correlation between different chemical variables is used to investigate whether some quantities can be evaluated from others, so that the measurement of the first quantities can be avoided (major and minor chemical components, traces), or whether the relationships between the groups of chemical variables can be reduced (e.g., acid and sterolic fraction). 

Moebius, F. F., Reiter, R. J., Hanner, M., Glossmann, H. High affinity of sigma rbinding sites for sterol isomerization inhibitors evidence for a pharmacological relationship with the yeast sterol C8-C7 isomerase, Brit. J. Pharmacol. 1997, 121, 1-6. 

Stage (4) Conversion of Squalene to the Four-Ring Steroid Nucleus When the squalene molecule is represented as in Figure 21-37, the relationship of its linear structure to the cyclic structure of the sterols becomes apparent. All... 

Methylation at C-4 of sterol nucleus was one of the other factors affecting activity enhancement. Thus, in general, 4-methylsterols (14,15) and 4,4-dimethylsterols (8,13) exhibited higher activity than 4-desmethylsterols. A similar structure-activity relationship was observed also in the HHPA-induced inflammation on mouse ear [35]. Whereas cholesterol (7) did not show inhibitory activity, several 4,4-dimethylcholestane derivatives, 0-12, exhibited activity. 4,4-Dimethylcholestane-3a,5a-diol (12) was the most potent inhibitor its activity was comparable to that of ursolic acid (210) [35]. Compound 12 reduced also the inflammation induced by teleocidin B (3), one of the indole alkaloid-type of tumor promoters [53]. 

Mauricio, J.C., Guijo, S., Ortega, J.M. (1991). Relationship between phospholipid and sterol contents in Saccharomyces cerevisiae and Torulaspora delbrueckii and their fermentation activity in grape musts. Am. J. Enol. Vitic., 42, 301-308. 

Food and Drug Administration (FDA) health claims" show that a relationship between a nutrient(s) or other substances and a disease or health-related condition, i.e., foods with soy protein, soluble fiber, and plant sterols, helps lower the risk of coronary heart disease (Table 8.5). These claims help individuals to select foods as either part of following recommended dietary guidelines, such as the TLC and Heart Healthy diets, or part of a self-treatment in response to You need to eat less fat and cholesterol and more fiber. ... 

The use of phytosterols as part of diet therapy to lower LDL-C and risk for CAD is supported by both the NCEP guidelines and the FDA s health claim about the relationship between the consumption of plant sterol and stand esters and reduced risk of coronary heart disease. This section briefly discusses the efficacy of the phytosterols as arguably the most effective dietary approach to lower plasma LDL-C in most types of subjects with the least impact on habitual diets. 

Initial steroid research involved isolation of sterols and bile acids from natural sources. DeFourcroy is generally credited with the discovery of cholesterol [57-88-5] (2) in 1789 (3). In 1848, cholic acid [81-25-4] (3) was isolated from the saponification of ox bile and its elementary composition determined as C24H4QO5 40 years later, Reintzer established the molecular formula of cholesterol as Degradative studies revealed the relationship of cholesterol... 

Phytosterols The relationship between total dietary phytosterol content and the fatty acid composition of the diet decreases with increasing saturated fatty acids, whereas the total dietary phytosterol content increases with increasing PUFA (86). Phytosterols consist of a mixture of cell membrane constituents that include free sterols, esterified steryls (e.g., esterified to phenolics), steryl glycosides, and acylated steryl glycosides (Table 2). 

Available literature solubility data of pure lipids belonging to major (fatty acids, mono-, di- and triacylglycerols, and fatty acid esters) and minor lipid classes (pigments, sterols, vitamins, and hydrocarbons) in SCCO2 were compiled (26, 27). These references (26, 27) contain exhaustive bibliography on lipid + SCCO2 binary systems. Literature data were correlated using Chrastil s equation, which is an empirical model used quite commonly to correlate the solubility of lipid components (30). This model is based on the formation of a solute-solvent complex on association of the solute and solvent molecules and establishes a linear relationship between In(solubility) and In(density) as follows ... 

Acuna-Cueva, R. Hueso-Urena, F. Caheza, N.A.J. Jimenez-Pulido, S.B. Moreno-Carretero, M.N. Martos, J.M.M. Quantitative stmcture-capillary column gas chromatographic retention time relationships for natural sterols (trime-thylsilyl esters) from olive oil. J. Am. Chem. Soc. 2000, 77, 627-630. 

Exploration of the area of imidazole-l-carboxamides has led to the discovery of prochloraz, a broad-spectrum fungicide for use on a variety of crops. Prochloraz and its analogues are inhibitors of ergosterol biosynthesis and structure-activity relationships in the area are discussed. In particular, the usefulness of an in vitro assay for sterol biosynthesis as a guide to the chemical effort is considered. Finally, the biological activity of prochloraz is briefly described. 

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