US4614616A
Expired / Lapsed
US
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Process for preparing 3β7β-dihydroxy-Δ5 -steroids
Assignee: Bayer Pharma AG
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Filing: 1983-09-26
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Granted: 1986-09-30
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Expires: 2003-09-26
Abstract
Abstract A process for preparing a 3β,7β-dihydroxy-Δ 5 -steroid of the formula ##STR1## wherein Q is ##STR2## and R 1 is hydrogen, trimethylacetyl, tert-butyldimethylsilyl, dimethyl-2-(3-methylbutyl)silyl or tribenzylsilyl, comprises fermenting a 3β-hydroxy-Δ 5 -steroid of the formula ##STR3## wherein Q is as defined above, and R 2 is hydrogen or alkanoyl of 2-6 carbon atoms, with a culture of Botryodiplodia malorum to obtain the corresponding 3β,7β-dihydroxy-Δ 5 -steroid; and, optionally, reacting the resultant product with trimethylacetic anhydride, tert-butyldimethylsilyl chloride, dimethyl-2-(3-methylbutyl)silyl chloride, or tribenzylsilyl chloride.
Inventors
- 👤 Karl Petzoldt
- 👤 Rudolf Wiechert
- 👤 Henry Laurent
- 👤 Klaus Nickisch
- 👤 Dieter Bittler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:56
CPC Classifications
C; C12; C12P; C12P33/00; C12P33/06; C07; C07J; C07J53/00; C07J53/002; C07J53/004; C07J53/008; C07J71/00; C07J71/0005; C07J71/001
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
40 words
A process for selectively blocking the 3β OH of a 3β,7β-dihydroxy-Δ 5 -steroid of the formula ##STR7## wherein Q is ##STR8## comprising reacting the steroid with tert-butyldimethylsilyl chloride, dimethyl-2-(3-methylbutyl)silyl chloride, or tribenzylsilyl chloride, thereby obtaining the corresponding 3β-blocked-7β-free(OH)-Δ 5 -steroid.
Claim 2
Dependent Claim
40 words
A process for selectively blocking the 3β OH of a 3β,7β-dihydroxy-Δ 5 -steroid of the formula ##STR7## wherein Q is ##STR8## comprising reacting the steroid with tert-butyldimethylsilyl chloride, dimethyl-2-(3-methylbutyl)silyl chloride, or tribenzylsilyl chloride, thereby obtaining the corresponding 3β-blocked-7β-free(OH)-Δ 5 -steroid.
Claim 3
Dependent Claim
25 words
A process of claim 1 wherein the blocking agent is tert-butyldimethylsilyl chloride and the reaction is carried out in the presence of an organic base.
Claim 4
Dependent Claim
25 words
A process of claim 1 wherein the blocking agent is dimethyl-2-(3-methylbutyl)silyl chloride and the reaction is carried out in the presence of an organic base.
Claim 5
Dependent Claim
25 words
A process of claim 1 wherein the blocking agent is tribenzylsilyl chloride and the reaction is carried out in the presence of an organic base.
Claim 6
Dependent Claim
17 words
A process of claim 2 wherein the organic base is pyridine, imidazole, triethylamine, 4-dimethylaminopyridine, lutidine, or collidine.
Claim 7
Dependent Claim
17 words
A process of claim 3 wherein the organic base is pyridine, imidazole, triethylamine, 4-dimethylaminopyridine, lutidine, or collidine.
Claim 8
Dependent Claim
17 words
A process of claim 4 wherein the organic base is pyridine, imidazole, triethylamine, 4-dimethylaminopyridine, lutidine, or collidine.
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) | 1989-09-29 | 1990-03-31 | 1990-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-29 | 1994-03-31 | 1994-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-29 | 1998-03-31 | 1998-09-30 | $7700.00 | Window Closed / Lapsed |