US4374060A
Expired / Lapsed
US
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Process for the preparation of cyclic hexapeptide
Assignee: Merck and Co Inc
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Filing: 1981-07-15
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Granted: 1983-02-15
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Expires: 2001-07-15
Abstract
Abstract There is disclosed a process for preparing a cyclic hexapeptide somatostatin analog, specifically cyclo (D-Trp-Lys-Val-Phe-N-Me-Ala-Tyr). The cyclic hexapeptide is synthesized in large quantities in a solution synthesis procedure. However, because of the unexpectedly rapid cyclization rate of this compound, conditions have been developed such that a much more concentrated solution, and thus smaller volumes of the reaction medium, may be employed than would be expected.
Inventors
- 👤 Ruth F. Nutt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 20:02
CPC Classifications
C; C07; C07K; C07K14/00; C07K14/435; C07K14/575; C07K14/655; C07K14/6555; Y; Y10; Y10S; Y10S930/00; Y10S930/01; Y10S930/16
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
83 words
A process for the preparation of Cyclo(D-Trp-Lys-Val-Phe-N-Me-Ala-Tyr) which comprises cyclizing at a molar concentration of from 0.5 to 0.001, in a solvent system consisting of N,N-dimethylformamide, dimethylsulfoxide, or mixtures thereof, the following linear peptide which may optionally be protected by one or more blocking groups: H-D-Trp-Lys-Val-Phe-N-Me-Ala-Tyr-OH wherein the reaction is carried out in the presence of a tertiary amine or sodium bicarbonate and diphenylphosphorylazide as a cyclizing agent at from -30° to +5° C. over a period of from 1 to 50 hours.
Claim 2
Dependent Claim
83 words
A process for the preparation of Cyclo(D-Trp-Lys-Val-Phe-N-Me-Ala-Tyr) which comprises cyclizing at a molar concentration of from 0.5 to 0.001, in a solvent system consisting of N,N-dimethylformamide, dimethylsulfoxide, or mixtures thereof, the following linear peptide which may optionally be protected by one or more blocking groups: H-D-Trp-Lys-Val-Phe-N-Me-Ala-Tyr-OH wherein the reaction is carried out in the presence of a tertiary amine or sodium bicarbonate and diphenylphosphorylazide as a cyclizing agent at from -30° to +5° C. over a period of from 1 to 50 hours.
Claim 3
Dependent Claim
18 words
The process of claim 1 wherein the reaction is carried out at a molar concentration of about 0.008.
Claim 4
Dependent Claim
11 words
The process of claim 1 wherein the tertiary amine is triethylamine.
Claim 5
Dependent Claim
12 words
The process of claim 1 wherein the inorganic base is sodium bicarbonate.
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) | 1986-02-14 | 1986-08-16 | 1987-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-14 | 1990-08-16 | 1991-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-14 | 1994-08-16 | 1995-02-15 | $7700.00 | Window Closed / Lapsed |