Steroid nitrogen compounds

QF-1 Polytrifluoropropyl methyl siloxane 250 Alcohols, Amino Acids, Steroids, Nitrogen Compounds... 

The oxygen atoms portrayed above can, in principle, be replaced by nitrogen atoms, although this has been verified by experiment only with 20-amino steroids. In view of the difficult access to 8/5-hydroxy steroids, these compounds have not been used for substitution reactions, but they fulfill all requirements for suecessful functionalizations at both C-18 and C-19. 

Actinomycetes can metabolize a wide variety of organic substrates, including organic compounds that are generally not metabolized, such as phenols and steroids. They are also important in the metabolism of heterocyclic compounds such as complex nitrogen compounds and pyrimidines [42,49]. The breakdown products of their metabolites are frequently aromatic, and these metabolites are important in the formation of humic substances and soil humus [42,49]. 

This section includes oxidations of alkanes and cycloalkanes, alkenes and cycloalkenes, dienes, alkynes, aromatic fluorocarbons, alcohols, phenols, ethers, aldehydes, ketones and carbohydrates, carboxylic acids, nitrogen compounds, and organoelement compounds, such as boron, phosphorus, sulfur, selenium, and iodine compounds, and steroids. 

The solvent extracts can be cleaned up by traditional column chromatography or by solid-phase extraction cartridges. This is a common cleanup method that is widely used in biological, clinical, and environmental sample preparation. More details are presented in Chapter 2. Some examples include the cleanup of pesticide residues and chlorinated hydrocarbons, the separation of nitrogen compounds from hydrocarbons, the separation of aromatic compounds from an aliphatic-aromatic mixture, and similar applications for use with fats, oils, and waxes. This approach provides efficient cleanup of steroids, esters, ketones, glycerides, alkaloids, and carbohydrates as well. Cations, anions, metals, and inorganic compounds are also candidates for this method [7],... 

Hydrogen abstraction under conditions similar to those in Section 3.8.1 may occur also from nitrogen compounds, with formation of amidyl free radicals. The results vary, depending on the substrate for example, 6-amino derivatives of steroids were converted into TV-substituted pyrrolidines [127], Medium-sized lactams underwent transannular cyclization to bicyclic lactams [128], and bicyclic carbinolamides afforded mainly -fragmentation products (Table 3.7). 

The amino-ketone (292) dimerised when liberated from its salt, giving a dihydropyrazine air-oxidation gave the pyrazine (293), which exhibited characteristic u.v. and c.d. features n — k and tt —> 7t ). ° Some novel fused heterocycles have been obtained by suitable condensations of 3-oxo- and 7-oxo-steroids with nitrogenous compounds cyanoguanidine, for example, affords diamino-pyrimidines (294), and 2,4,5,6-tetra-aminopyrimidine reacts with a 2-bromo-3-oxo-steroid to give a diamino-pteridine. 

Molecular structure and thermochemistry are interrelated here for species chosen from contributions to the earlier Volume 3 of this book series. Discussion includes halogenated species gaseous nonmetal dioxides X-Y bond-containing species (X,Y = C, N, O) small carbon molecules arenols and substituted arenes steroids aromatic carbocycles difluoramines and nitro compounds selenium- and tellurium-nitrogen compounds. 

In summary, clavaric acid is a non-nitrogenous compound that inhibits FPTase by competing with Ras-peptide. This led to the identification, design and synthesis of very potent inhibitors that compete with either of the two enzyme substrates (ie., corticosteroids and des-A steroids). 

Oxygen levels in the VGO parallel the nitrogen content. Thus, the most identified oxygen compounds are phenols and carboxyUc acids, frequendy called naphthenic acids. These may account for from ppm to neady 3% of a VGO. The presence of numerous complex naphthenic and naphtheno aromatic acid stmctures in cmde oils, especially immature forms, has been shown (34). Among the different stmctures a number of specific steroid carboxyUc acids have been identified. 

As is the case with other classes of steroids, inclusion of nitrogen atoms into corticoids has met with only limited pharmacological success. Compounds... 

Another interesting alkaloid is tubocurarine chloride (14), with a bisbenzyliso-quinoline structure. It is the active principle of tubocurare, an arrow poison used by Indians in South America and medicinally used as a muscle relaxant. However, the source, the leaves of the tropical rainwood liane Chondodenron tomento-sum, is not easily accessible and the compound exhibits unwanted side-effects. Investigations showed that the basic structure can be replaced by an appropriate steroid skeleton with two nitrogen substituents at the right distance (see next section). 

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