Oxosteroids, synthesis

In 3-oxosteroid A4-steroid 5)3-reductase deficiency, key intermediates for cholic and chenodeoxycholic synthesis, 7a-hydroxy-4-cholesten-3-one and 7a,12a-dihy-droxy-4-cholesten-3-one undergo side-chain oxidation and conjugation to produce... 

Free sulfilimines are known to undergo conjugate-type addition to electrophilic alkenes to afford aziridines and enamines "1 -1,3. A useful method for the preparation of 16,17starting materials for the synthesis of various compounds with a wide spectrum of physiological activity114, involves the addition of free sulfilimines to ,fi-unsatu-rated oxosteroids. Thus, S,S-diphenylsulfilimine 35 reacts with steroidal cnones (e.g., 34 and... 

Defective Bile Acid Synthesis. Specific defects in bile acid synthesis have long been postulated. Two inborn errors of bile acid synthesis, both associated with idiopathic neonatal hepatitis, A -3-oxosteroid 5-P-reductase deficiency and 3-p-hydroxy-dehydrogenase isomerase deficiency, have been described. A third disorder associated with defective bile... 

Setchell, K.D., Suchy, F.J., Welsh, M.B., Zimmer-Nechemias, L., Heubi, J., Balistreri, W.F. 1988. D -3-oxosteroid 5(5-reductase deficiency described in identical twins with neonatal hepatitis. A new inborn error in bile acid synthesis. J. Clin. Invest. 82 2148-2157. 

Other Reactions. A synthesis of 3-deoxy-A-homovitamin D3 has been reported which involved treatment of 5a-cholest-6-en-3-one with diazomethane to give a mixture of the A-homoketones. In contrast to the behaviour of diazomethane, diazocyclopropane reacts with A -3-oxosteroids to give ring-expanded products in the absence of Lewis acid catalysts. ... 

Fig. 32.1. The classical ( neutral ) pathway for the synthesis of bile acids from cholesterol, where the modification of the steroid nucleus occurs prior to side-chain modification. Also illustrated are the inborn errors of bile acid synthesis and the resulting abnormal metabolites. 32.1, 3) -hydroxy-A -C27-steroid dehydrogenase (3) -HSDH) deficiency 32.2, A -3-oxosteroid 5 -reductase deficiency 32.3, sterol 27-hydroxylase deficiency (cerebrotendinous xanthomatosis, CTX) PD, peroxisomal disorders (defects of peroxisome biogenesis and peroxisomal j -oxidation). The abnormal metabolites that are readily detected by analysis of urine by LSI-MS are shown in boxes. Cholic acid can also be synthesised from 5 -cholestane-3a,7a,12a,25-tetrol this is the so-called microsomal or 25-hydroxylase pathway of cholic acid synthesis, which provides an alternative route for side-chain modification other than peroxisomal j -oxidation...

An androgenic steroid synthesized in the ovaries, testes and adrenals. It is an intermediate in the synthesis oif testosterone. Together with androstenedione, it constitutes one of the main androgens secreted by the adrenal cortex. It is one of the 17-oxosteroids which can be measured by the Zimmermann reaction. 

An ingenious route for the synthesis of 11-oxosteroids was proposed by Friedmann and Robinson (Scheme 13) [251, 252]. On condensation with ethyl Q -acetyladipate, compound (141) obtained from the diketone (140) ... 

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