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US4420628A
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Process for preparing threo-2-hydroxy-3-(4-methoxyphenyl)-3-(2-nitrophenylthio)-propionic ester
Assignee: Tanabe Pharma Corp
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Filing: 1982-02-08
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Granted: 1983-12-13
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Expires: 2002-02-08
Abstract
Abstract A threo-2-hydroxy-3-(4-methoxyphenyl)-3-(2-nitrophenylthio)propionic ester of the formula: <IMAGE> wherein R is an ester residue, is prepared by condensing a trans-3-(4-methoxyphenyl)glycidic ester of the formula: <IMAGE> wherein R is the same as defined above, with 2-nitrothiophenol in the presence of a Lewis acid.
Inventors
- 👤 Hirozumi Inoue
- 👤 Tomiki Hashiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:13
CPC Classifications
C; C07; C07C; C07C67/00; C07C323/00; C07F; C07F7/00; C07F7/22; C07F7/226
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
100 words
A method for preparing a threo-2-hydroxy-3-(4-methoxyphenyl)-3-(2-nitrophenylthio)propionic ester of the formula: ##STR10## wherein R is an ester residue, which comprises condensing a trans-3-(4-methoxyphenyl)glycidic ester of the formula: ##STR11## wherein R is the same as defined above, with 2-nitrothiophenol in the presence of a Lewis acid selected from the group consisting of boron trifluoride, stannous halide, stannic halide, zinc halide, ferrous halide, ferric halide, cuprous halide, cupric halide, antimony trihalide, antimony pentahalide, cadmium halide, nickel halide, stannous alkanoate, stannic alkanoate, zinc alkanoate, zinc salicylate, zinc oxalate, sulfuric acid, perhalogenic acid, alkanoic acid, aromatic carboxylic acid, sulfonic acid, phosphoric acid and polyphosphoric acid.
Claim 2
Independent Claim
100 words
A method for preparing a threo-2-hydroxy-3-(4-methoxyphenyl)-3-(2-nitrophenylthio)propionic ester of the formula: ##STR10## wherein R is an ester residue, which comprises condensing a trans-3-(4-methoxyphenyl)glycidic ester of the formula: ##STR11## wherein R is the same as defined above, with 2-nitrothiophenol in the presence of a Lewis acid selected from the group consisting of boron trifluoride, stannous halide, stannic halide, zinc halide, ferrous halide, ferric halide, cuprous halide, cupric halide, antimony trihalide, antimony pentahalide, cadmium halide, nickel halide, stannous alkanoate, stannic alkanoate, zinc alkanoate, zinc salicylate, zinc oxalate, sulfuric acid, perhalogenic acid, alkanoic acid, aromatic carboxylic acid, sulfonic acid, phosphoric acid and polyphosphoric acid.
Claim 3
Dependent Claim
40 words
The method according to claim 1, wherein the Lewis acid is selected from the group consisting of boron trifluoride, stannous halide, stannic halide, zinc halide, stannous alkanoate, stannic alkanoate, zinc alkanoate, zinc salicylate, zinc oxalate, perhalogenic acid and sulfuric acid.
Claim 4
Dependent Claim
48 words
The method according to claim 1, wherein the Lewis acid is selected from the group consisting of boron trifluoride, stannous chloride, stannous fluoride, stannous bromide, stannous iodide, stannic chloride, stannic bromide, stannic iodide, zinc chloride, stannous octylate, stannous stearate, stannic octylate, zinc acetate, perchloric acid and sulfuric acid.
Claim 5
Dependent Claim
22 words
The method according to claim 1, 2, or 3, wherein the ester residue (R) is alkyl of one to 4 carbon atoms.
Claim 6
Dependent Claim
27 words
The method according to claim 4, wherein the condensation is carried out in a solvent at a temperature in the range of from 0° to 80° C.
Claim 7
Dependent Claim
27 words
The method according to claim 4, wherein the condensation is carried out in a solvent at a temperature in the range of from 10° to 50° C.
References Cited (Backward Citations)
JPS4948305A
Cited
JPS4936221A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-12 | 1987-06-13 | 1987-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-12 | 1991-06-13 | 1991-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-12 | 1995-06-13 | 1995-12-13 | $7700.00 | Window Closed / Lapsed |