- Method for continuously preparing rosuvastatin intermediate by micro-channel modular reaction device
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The invention discloses a method for continuously preparing a rosuvastatin intermediate by a micro-channel modular reaction device. The method includes the steps: performing reaction on isopropanol solution of fluorobenzaldehyde and isopropanol solution o
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- Efficient Construction of the Nucleus of Rosuvastatin Calcium
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A novel and efficient five-step synthetic route, including a Biginelli reaction, dehydrogenation, chlorination, sulfonamidation, and reduction, for the core of Rosuvastatin was established. All steps were systematically studied. Tert-butylhydroperoxide aqueous solution was applied in the dehydrogenation instead of nitric acid. N,N-dimethylaniline was employed as a catalyst to accelerate the chlorination proceeding smoothly, and its catalytic mechanism is discussed. In the sulfonamidation, the conversion of compound 5 was obviously improved by use of NaH and acetonitrile. In addition, two sulfonamidation side products 6 and 7 were detected and isolated. Thus, under the optimized reaction conditions, the target product was obtained in 60.4% total yield, much higher than the reported yield (36.4%).
- Zhou, Yingtao,Lin, Chenhui,Xing, Yuzhi,Chen, Ligong,Yan, Xilong
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p. 1898 - 1903
(2017/05/29)
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- METHOD FOR PRODUCING PYRIMIDINE COMPOUND
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Compound (II) and compound (III) are reacted to give compound (IVa) and/or compound (IVb); which are/is then reacted with compound (V) to give compound (I). wherein X is a methylthio group and the like, R1 and R2 are each a lower alkyl group optionally having substituent(s), an aryl group optionally having substituent(s) and the like, R3 is a lower alkyl group, R4 is a hydrogen atom, a lower alkyl group optionally having substituent(s) and the like, and Q is a carboxylate group and the like.
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Page/Page column 14
(2010/11/28)
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- Oxidative dehydrogenation of dihydropyrimidinones and dihydropyrimidines
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(Chemical Equation Presented) A mild, practical procedure for oxidative dehydrogenation with catalytic amounts of a Cu salt, K2CO 3, and tert-butylhydroperoxide (TBHP) as a terminal oxidant has been developed. This oxidation procedure is generally applicable to dihydropyrimidinones and most dihydropyrimidines.
- Yamamoto, Kana,Chen, Ye Grace,Buono, Frederic G.
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p. 4673 - 4676
(2007/10/03)
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- PROCESS FOR THE PREPARATION OF PYRIMIDINE DERIVATIVES
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There is described a process for the preparation of compounds of formula (1) starting from the reaction of the compounds of formulae (24), (25) and (26) to form the compound of formula (23), wherein in each case R1, R2 and R3 are each independently of the others an unsubstituted or substituted organic radical; R4 is hydrogen, unsubstituted or substituted C1-C8alkyl, C1-C8alkoxy, phenoxy or benzyloxy, or halogen; Y1 and Y2 are each independently of the other hydrogen or a protecting group, or Y1 and Y2 together are a protecting bridge; and X1 is hydrogen, an organic radical or a cation; and also novel intermediates.
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