EP0137445A2
Expired / Lapsed
EP
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Process for c-methylation of 2-methylbutyrates
Assignee: Merck and Co Inc
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Filing: 1984-10-02
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Granted: —
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Expires: 2004-10-02
Abstract
Abstract Mevinolin, compactin and dihydro- and tetrahydro derivatives thereof are converted to more active HMG-CoA reductase inhibitors by C-methylation of the natural 2(S)-methylbutyryloxy side chain to form a 2,2-dimethyl- butyryloxy side chain.
Inventors
- 👤 Meyer Sletzinger
- 👤 Thomas R. Verhoeven
- 👤 Ralph P. Volante
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 06:39
CPC Classifications
C; C07; C07D; C07D309/00; C07D309/16; C07D309/28; C07D309/30; A; A61; A61P; A61P3/00; A61P3/06
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
75 words
A process for the preparation of a compound of structural formula II: which comprises treatment of a compound of structural formula I as its alkali metal salt with a methyl halide and a strong base followed by acidification and lactonization wherein the dotted lines represent possible double bonds there being 0, 1 or 2 double bonds; n represents 1, 2, 3 or 4; and R is 1) methyl, 2) hydroxy, or 3) C 1-4 alkoxy.
Claim 2
Dependent Claim
75 words
A process for the preparation of a compound of structural formula II: which comprises treatment of a compound of structural formula I as its alkali metal salt with a methyl halide and a strong base followed by acidification and lactonization wherein the dotted lines represent possible double bonds there being 0, 1 or 2 double bonds; n represents 1, 2, 3 or 4; and R is 1) methyl, 2) hydroxy, or 3) C 1-4 alkoxy.
Claim 3
Dependent Claim
86 words
The process of Claim 1 which comprises treatment of Compound I with methyl iodide or methyl bromide in an ethereal solvent at -60° to -25°C in the presence of an alkali metal amide of formula +- MNR 1 R 2 where M is a cation derived from sodium, potassium or lithium and R 1 and R 2 are C l-3 alkyl or R 1 and R 2 are joined together to form a 5 or 6-membered heterocyclic ring with the nitrogen to which they are attached.
Claim 4
Dependent Claim
28 words
The process of Claim 2 wherein the ethereal solvent is tetrahydrofuran, the temperature is -35 to -30°C and the alkali metal amide is lithium diethylamide or lithium pyrrolidide.
Claim 5
Dependent Claim
52 words
The process of Claim 1 wherein in Compounds I and II there is no double bond, one double bond in the 3,4-position, or two bonds in the 3,4 and 4a,5-positions; n is 1 or 2; and R is methyl in the 2-position if n=l and in the 2 and 6-positions if n=2.
Claim 6
Dependent Claim
52 words
The process of Claim 2 wherein in Compounds I and II there is no double bond, one double bond in the 3,4-position, or two bonds in the 3,4 and 4a,5-positions; n is 1 or 2; and R is methyl in the 2-position if n=l and in the 2 and 6-positions if n=2.
Claim 7
Dependent Claim
53 words
The process of Claim 3 wherein in Compounds I and II there is no double bond, one double bond in the 3,4-position, or two double bonds in the 3,4 and 4a,5-positions; n is 1 or 2; and R is methyl in the 2-position if n=1 and in the 2 and 6-positions if n=2.
Claim 8
Dependent Claim
13 words
The process of Claim 1 for the preparation of the compound of formula:,
Claim 9
Dependent Claim
13 words
The process of Claim 2 for the preparation of the compound of formula:
Claim 10
Dependent Claim
13 words
The process of Claim 3 for the preparation of the compound of formula:
References Cited (Backward Citations)
No citation records indexed.
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