- Preparation method for etonogestrel and desogestrel important intermediate
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The invention discloses a preparation method for an etonogestrel and desogestrel important intermediate. The preparation method is characterized in that the intermediate is prepared from a compound shown as a formula (2) which is taken as an initial raw material. The preparation method obtains the object product in high yield through five steps, and the whole process is mild in reaction condition,low in danger and simple in operation. The preparation method is much better than known literature processes no matter from respects of atomic economy, safety and price cost or the respect of storageand transportation, and the problems of high toxicity and non-stabilization of used reagents and intermediate products and severe pollution on environment of by-products can be avoided. The prepareddesogestrel and etonogestrel important intermediate (1) is mild in reaction condition, relatively complete in reaction, high in chemical selectivity and high in reaction yield, and solvents can be recycled, so that convenient industrial implementation can be realized. Reaction general formulas are shown as follows.
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- TOTAL SYNTHESIS OF ENANTIOPURE DESOGESTREL
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The present invention relates to a total synthesis of desogestrel and derivatives thereof, and to intermediate compounds of this synthesis.
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Page/Page column 34-35
(2009/04/25)
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- Enantioselective total synthesis of the oral contraceptive desogestrel by a double heck reaction
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A novel enantioselective total synthesis of the oral contraceptive desogestrel (2) is described, in which the tetracyclic steroid core is formed by a sequence of two consecutive Heck reactions. Conversion of the known enantiopure diketone 7 led to the chiral bicycle 6 which was used for a diastereoselective intermolecular Heck reaction with vinyliodide 5 to give 15. In the following intramolecular Heck reaction, the tetracyclic ring system was formed to give 4, from which the synthesis of desogestrel (2) was furnished.
- Tietze, Lutz F.,Krimmelbein, Ilga K.
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experimental part
p. 1541 - 1551
(2009/04/04)
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- A short enantioselective total synthesis of the third-generation oral contraceptive desogestrel
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Desogestrel (1) has been synthesized enantioselectively by a 14-step process from the known and readily available precursor 3, as outlined in Chart 2. At the heart of this process is the short, convergent, and stereocontrolled method for forming the tetracyclic ring system and the critical 11-exomethylene function, that is, the sequence of steps 6 → 8 → → 12. All steps of the synthesis proceed in good yield.
- Corey,Huang, Alan X.
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p. 710 - 714
(2007/10/03)
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