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5-Fluorocytosine synthesis
- Product Name:5-Fluorocytosine
- CAS Number:2022-85-7
- Molecular formula:C4H4FN3O
- Molecular Weight:129.09
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An alternative way of synthesis consists of making flucytosine from a precursor of fluorouracil—5-fluoro-2-methylthiouracil (30.1.3.2) using a somewhat analogous scheme. Treating 5-fluoro-2-methylthiouracil (30.1.3.2) with phosphorous pentachloride gives 4-chloro-5-fluoro-2-methylthiopyrimidine (35.4.5), which upon being reacted with ammonium is transformed into 4-amino-5-fluoro-2-methylthiopyrimidine (35.4.6). Hydrolysis of the methylthiovinyl fragment using concentrated hydrobromic acid gives the desired flucytosine.
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99429-06-8
2 suppliers
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2022-85-7
752 suppliers
$5.00/5g
Yield:2022-85-7 98.1%
Reaction Conditions:
with ammonia in hydrogenchloride;ethanol;water;
Steps:
4 Preparation of 5-fluorocytosine from 2,5-difluoro-4-chloropyrimidine
EXAMPLE 4 Preparation of 5-fluorocytosine from 2,5-difluoro-4-chloropyrimidine 15.05 g (0.1 mole) of 2,5-difluoro-4-chloropyrimidine were stirred in 30 ml of 37% strength aqueous hydrochloric acid at 50° C. for 2 hours. After the mixture had cooled, it was neutralized with 33% strength aqueous ammonia solution. The mixture was then diluted with 100 ml of ethanol and a further 20 ml of aqueous 33% strength ammonia solution were added. The mixture was subsequently stirred at room temperature for 2 hours. Thereafter, it was concentrated in vacuo, the residue was taken up in 60 ml of water and the solid obtained was filtered off with suction, washed with water and dried. 11.5 g of product with a melting point of 294° to 296° C. were obtained, corresponding to a yield of 98.1% of theory.
References:
US4703121,1987,A
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71-30-7
736 suppliers
$5.00/10g
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2022-85-7
752 suppliers
$5.00/5g
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1993-63-1
101 suppliers
$14.00/5g
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2022-85-7
752 suppliers
$5.00/5g
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1312324-60-9
8 suppliers
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2022-85-7
752 suppliers
$5.00/5g
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1310078-72-8
4 suppliers
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2022-85-7
752 suppliers
$5.00/5g