US4579747A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dipeptide crystals, and process for their production
Assignee: Ajinomoto Co Inc
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Filing: 1984-03-13
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Granted: 1986-04-01
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Expires: 2004-03-13
Abstract
Abstract α-L-aspartyl-L-phenylalanine methyl ester II type crystals consisting of two types of crystals, II A and II B type, which interconvert from one to the other depending upon the equilibrium moisture content of the crystals, wherein one type of crystal, II a , exhibits X-ray diffraction peaks at angles of diffraction of at least 20.6°, 21.2°, 5.0° and 11.1°, and the other type of crystal, II B , exhibits X-ray diffraction peaks at angles of diffraction of at least 15.2°, 11.1°, 19.6° and 4.5°, as measured by X-ray diffractometer using CuK.sub.α radiation and wherein the equilibrium moisture content of either of the crystals at a relative humidity of 78% is not higher than about 3%.
Inventors
- 👤 Katsumi Sugiyama
- 👤 Toshiyuki Ozawa
- 👤 Nobuya Nagashima
- 👤 Yoshinobu Uchida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:21
CPC Classifications
C; C07; C07K; C07K5/00; C07K5/04; C07K5/06; C07K5/06104; C07K5/06113; C07K5/06121; C07K5/0613; A; A23; A23L; A23L27/00; A23L27/30; A23L27/31; A23L27/32
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
159 words
α-L-aspartyl-L-phenylalanine methyl ester II crystals consisting of two kinds of crystals, II A and II B , which interconvert from one to the other depending upon the equilibrium moisture content of the crystals, wherein one type of crystal, II A , exhibits X-ray diffraction peaks at angles of diffraction of at least 20.6°, 21.2°, 5.0° and 11.1°, and the other type of crystal, II B type, exhibits X-ray diffraction peaks at angles of diffraction of at least 15.2°, 11.1°, 19.6°, 4.5°, as measured by X-ray diffractometer using CuK.sub.α radiation and wherein the equilibrium moisture content of either of the crystals at a relative humidity of 78% is not higher than about 3% wherein said α-L-aspartyl-L-phenylalanine methyl ester II crystals are prepared by drying α-L-aspartyl-L-phenylalanine methyl ester I crystals at a temperature in the range of about 80° C. to less than 150° C. for a time sufficient to convert substantially all of the I crystals into the II crystals.
Claim 2
Dependent Claim
159 words
α-L-aspartyl-L-phenylalanine methyl ester II crystals consisting of two kinds of crystals, II A and II B , which interconvert from one to the other depending upon the equilibrium moisture content of the crystals, wherein one type of crystal, II A , exhibits X-ray diffraction peaks at angles of diffraction of at least 20.6°, 21.2°, 5.0° and 11.1°, and the other type of crystal, II B type, exhibits X-ray diffraction peaks at angles of diffraction of at least 15.2°, 11.1°, 19.6°, 4.5°, as measured by X-ray diffractometer using CuK.sub.α radiation and wherein the equilibrium moisture content of either of the crystals at a relative humidity of 78% is not higher than about 3% wherein said α-L-aspartyl-L-phenylalanine methyl ester II crystals are prepared by drying α-L-aspartyl-L-phenylalanine methyl ester I crystals at a temperature in the range of about 80° C. to less than 150° C. for a time sufficient to convert substantially all of the I crystals into the II crystals.
Claim 3
Dependent Claim
41 words
The II A and II B crystals according to claim 1, wherein said II A crystals have an equilibrium moisture content of about 0.9 to 3.0% and said II B crystals have an equilibrium moisture content of about 0.9% or less.
Claim 4
Dependent Claim
50 words
A process for the production of α-L-aspartyl-L-phenylalanine methyl ester II crystals, which comprises drying α-L-aspartyl-L-phenylalanine methyl ester I crystals at a temperature in the range of about 80° C. to less than 150° C. for a time sufficient to convert substantially all of the I crystals into the II crystals.
Claim 5
Dependent Claim
50 words
A process for the production of α-L-aspartyl-L-phenylalanine methyl ester II crystals, which comprises drying α-L-aspartyl-L-phenylalanine methyl ester I crystals at a temperature in the range of about 80° C. to less than 150° C. for a time sufficient to convert substantially all of the I crystals into the II crystals.
Claim 6
Dependent Claim
15 words
The process according to claim 3, wherein the crystals are dry crystals or wet crystals.
Claim 7
Dependent Claim
20 words
The process according to claim 3, wherein the crystals are dried with a tray dryer, air dryer or fluidized dryer.
Claim 8
Dependent Claim
38 words
The process according to claim 3, wherein the I crystals are dried with a gas stream dryer and the dried crystals are maintained at about 80° C. or higher so as to be converted into the II crystals.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-03-31 | 1989-09-30 | 1990-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-31 | 1993-09-30 | 1994-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-31 | 1997-09-30 | 1998-04-01 | $7700.00 | Window Closed / Lapsed |