Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | Acetylethanolamine | HCID 8880 | — |
| Reactant | Isobutyl chloroformate | HCID 62365 | — |
| Reactant | (4S)-5-(Methoxycarbonyl)-2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid | HCID 748474 | — |
| Solvent | Tetrahydrofuran | HCID 8028 | — |
| Solvent | Ethyl Acetate | HCID 8857 | — |
| Product | HCID 59880457 | HCID 59880457 | — |
Reaction Steps
The authentic (R)-form of the title compound was prepared as follows. That is, 5 mg of (S)-(+)-1,4-dihydro-2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-3-pyridinecarboxylic acid prepared according to the method described by Shibanuma et al. (Chem. Pharm. Bull., 28(9), 2809-2812 (1980)) was dissolved in 0.5 ml of tetrahydrofuran. Then 2 μl of isobutyl chloroformate was added to the solution. After stirring for 10 minutes, 6 μl of triethylamine and 30 μl of N-acetyl-ethanolamine were added to the mixture followed by stirring for further 2 hours. After 5 ml of ethyl acetate was added to the reaction mixture, the mixture was washed with water and the resulting organic layer was dried over anhydrous sodium sulfate. The solvent was then distilled off. The residue thus obtained was purified on a preparative silica gel TLC (developing system, toluene-acetone; 1:1) to obtain 3 mg of the authentic (R)-form. The thus obtained authentic (R)-form compound showed the same residence time (14.0 minutes; moving phase 2.5% isopropanol/0.01M phosphate buffer (pH 7.1), flow rate: 0.8 ml/min) as that of the title compound obtained above on the column for optical resolution described above. With respect to the (S)-form, the residence time was 8.4 minutes under the same conditions.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US05635395 |
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| Source dataset | uspto-grants-1997_06 |
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| ORD ID | ord-ff68ed82d10d4f99af62c0ee3d3ed828 |
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| Source note | uspto-grants-1997_06 |
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