Synthesis androstane type

Androstane type of brassinosteroids, synthesis, 59-60 Antheridiol, synthesis, 37 Arthropods, effect of brassinosteroids, 268-275... 

Table 2 Nuclear receptors (NR) for enzyme inducers. Enzyme inducers are now known to act as ligands to nuclear receptors, leading to gene activation and increased synthesis of the enzyme. Affinity of inducers to die receptors is now known to be responsible for the differential induction potential and can explain die observed species-differences in induction. The receptors tabulated are aryl hydrocarbon receptors (AhR), constituitively androstane receptor (CAR), pregnane X receptor (PXR), and glucocorticoid receptor (GR). The isoforms in bold type are the major isoform regulated by the corresponding receptors.

FIGURE 11.54 Libraries of type 3 17 3-hydroxysteroid dehydrogenase inhibitors. (From Maltais, R., Luu-The, V., and Poirier, D., Parallel solid-phase synthesis of 3 3-peptido-3 -hydroxy-5 -androstan-17-one derivatives for inhibition of type 3 17P-hydroxysteroid dehydrogenase, Bioorg. Med. Chem., 9, 3101, 2001 Maltais, R., Luu-The, V., and Poirier, D., Synthesis and optimization of a new family of type 17P-hydroxysteroid dehydrogenase inhibitors by parallel liquid phase chemistry, J. Med. Chem., 45, 640, 2002.)... 

Maltais, R., Luu-The, V., and Poirier, D., Parallel solid-phase synthesis of 3 3-peptido-3a-hydroxy-5a-androstan-17-one derivatives for inhibition of type 3 17 3-hydroxysteroid dehydrogenase, Bioorg. Med. Chem., 9, 3101, 2001. 

A considerably greater number of new data has been obtained for syntheses by the CD — B - A route. Various modifications of the synthesis of des-A-estranes (27 R =H) and des-A-androstanes (27 R = Me) by the addition of ring B to CD fragments of type (26) have been described [1120, 1121]. The monocyclic triketone (28) has been reduced asymmetrically by the mold Rhizopus arrhizus to the 17iS-.hydroxy derivative (29) possessing the natural configuration. Acid cyclization of (29) yielded the ( -enantiomer (30), which was subsequently converted into ( -estradiol in accordance with Scheme 115 [1122]. 

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