Hydrogen Estrone

The most recent, and probably most elegant, process for the asymmetric synthesis of (+)-estrone appHes a tandem Claisen rearrangement and intramolecular ene-reaction (Eig. 23). StereochemicaHy pure (185) is synthesized from (2R)-l,2-0-isopropyhdene-3-butanone in an overall yield of 86% in four chemical steps. Heating a toluene solution of (185), enol ether (187), and 2,6-dimethylphenol to 180°C in a sealed tube for 60 h produces (190) in 76% yield after purification. Ozonolysis of (190) followed by base-catalyzed epimerization of the C8a-hydrogen to a C8P-hydrogen (again similar to conversion of (175) to (176)) produces (184) in 46% yield from (190). Aldehyde (184) was converted to 9,11-dehydroestrone methyl ether (177) as discussed above. The overall yield of 9,11-dehydroestrone methyl ether (177) was 17% in five steps from 6-methoxy-l-tetralone (186) and (185) (201). 

The hydrogenation of ring A aromatic steroids over ruthenium occurs, almost invariably, from the a side and all substituents on the original aromatic ring are cis in the resulting cyclohexane. Estrone (62) is hydrogenated over ruthenium to 5a,10a-estrane-3/3,17j6-diol (63) in 85-90% yield. 

Under certain conditions surface catalytic deuterations can lead to the exchange of benzylic hydrogens. An example in the steroid field is the exchange of the benzylic hydrogens in estrone methyl ether (42) with deuterium in the presence of palladized charcoal." " According to mass spectrometric analysis, the product (43) contains three deuteriums (83 %), which have been assigned to the 6- and 9a-positions on the basis of NMR evidence." " ... 

A highly efficient construction of the steroidal skeleton 166 is reported by Kametani and coworkers111 in the intramolecular Diels-Alder reaction of the a, jS-unsaturated sulfone moiety of 165 (equation 117). Thus, when the sulfone 165 is heated in 1,2-dichlorobenzene for 6h, the steroidal compound 166 can be obtained in 62% yield. The compound 166 produces estrone (167) by elimination of benzenesulfinic acid and subsequent hydrogenation of the formed double bond. The stereoselectivity of the addition reflects a transition state in which the p-tosyl group occupies the exo position to minimize the steric repulsion between methyl and t-butoxy groups and the o-quinodimethane group as shown in equation 117. 

Reduction of dienes incorporated into steroid structures may lead to different configurations in the products. For example, treatment of 8(9),14(15)-bisdehydroestrone 42 (R = H) for four hours at room temperature with twenty equivalents of trifluoroacetic acid and two equivalents of triethylsilane leads to an ionic hydrogenation product mixture containing the natural 8/1,9a,14a-estrone 43 as a minor component (11%) and the 8a,9/i, l 4/i-isomcr 44 as the major component (83%) (Eq. 92).241 The related methyl ether (42, R = Me) behaves in a similar fashion.241 The yield of natural isomer 46 formed from the methyl ether of A8(9),i4(i5)-bigdehydroestradiol analog 45 increases from 22 to 34%, and that of... 

An analogous way of making estrone is demonstrated by starting from 1,4,6-androstatrien-3,17-dione (28.1.15), which when heated to 600 °C is also aromatized and releases methane molecule, forming 8,9-dihydroequilenin. The double bond in this molecule at Cg - Cy is reduced by hydrogen over a palladium catalyst, giving the desired estrone (28.1.9). 

Androst-4-ene-3,ll,17-trione, 88, 377, 409 di-Androst-5-en-3/3-oI, 199 Androst-5-en-17-ol-3-one, 32 Androst-l-en-3-one, 152 Androst-4-en-3 -one, 152 5a-Androst-8-en-l 1-one, 189 5 -Androst-8(14)-en-15-0ne, 155 Anhydrous hydrogen fluoride, 425 Aqueous hydrogen fluoride, 435 Argentic picolinate, 241 17a-aza-D-homo-estrone methyl ether, 163... 

Hydrogenation of d,l-9(ll)-dehydroestrone in tetrahydrofuran in the presence of Pd/CaC03 yields the estrone, melting point 251°-252°C (from acetone). 

What is the DU of estrone, a female sex hormone Use the number of carbons and oxygens in estrone to calculate the number of hydrogens it has. 

In complete contrast to the above results is the oxidation of the estrone (20) by hydrogen peroxide in hydrogen fluoride/antimony tetrafluoride. When subjected to hydroxylating conditions using this reagent, the estrone (20) gave a poor-yielding mixture of the oxidized products (21-23 Scheme 8). 

Figure 25 (a) The aromatase activity of P450 enzymes in which androstenedione is converted to estrone via oxidative deformylation (b) The concerted and radical mechanism of deformylation via breakdown of a peroxohemiacetal intermediate formed by nucleophilic attack of the ferric-hydroperoxo intermediate on the aldehyde (c) Abstraction of a alcohol hydrogen leads to the formation of a ketone rather than a ring... 

SYNS CONESTORAL ESTRA-1,3,5(10)-TRIEN-17-ONE, 3-(SULFOXYl-, SODIUM SALT (9CI) ESTRONE, HYDROGEN SULFATE, SODIUM SALT ESTRONE SULFATE SODIUM ESTRONE SULFATE SODIUM SALT ESTRONE-3-SULFATE SODIUM SALT EVEX MORESTIN OESTRONE-3-SULPHATE SODIUM SALT SODIUM ESTRONE SULFATE SODIUM ESTRONE-3-SULFATE... 

Conjugated Estrogens Esterified Estrogens Estrone, Equilin and 17a-dihyroeuilin (free steroids) 15M X 0.25mm I.D. fused Silica capillary bonded with G19 (0.25 pm) Hydrogen 220 FID 3-O-Methylestrone USP (24, pp. 681 and 683)... 

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