Patent US3884945A successfully refreshed from Google Patents.
US3884945A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synthesis of steroids by cyclization in nitro solvents
Assignee: Leland Stanford Junior University
•
Filing: 1973-04-26
•
Granted: 1975-05-20
•
Expires: 1993-04-26
Abstract
Abstract Synthesis of steroids by cyclization of a dienyne cyclization substrate to a steroid or A-nor steroid employing a primary or secondary aliphatic nitro compound as solvent, thereby forming an oxime ether group at the C-17 position of the resulting steroid (or at the corresponding position of the resulting A-nor steroid where that is the product of cyclization). This oxime group can be converted to an hydroxy group by reductive cleavage. Conversion of the cyclization products to steroids such as 17hydroxypregnan-20-ones and testosterone is facilitated. The method is also applied to cyclization of suitable substrates to bicyclic products.
Inventors
- 👤 William S Johnson
- 👤 Douglas R Morton
- 👤 Michael B Gravestock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:08
CPC Classifications
C; C07; C07J; C07J1/00; C07J1/0003; C07J1/0011; C07J1/0018; C07J1/0022; C07J41/00; C07J41/0033; C07J41/005; C07J7/00; C07J7/0005; C07J7/001; C07J7/004; C07J7/0045; C07J75/00; C07J75/005
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
15 words
IN THE METHOD OF CYCLIZING A SUBSTRATE HAVING IN ITS MOLECULE THE SKELETAL STRUCTURE A
Claim 2
Dependent Claim
15 words
IN THE METHOD OF CYCLIZING A SUBSTRATE HAVING IN ITS MOLECULE THE SKELETAL STRUCTURE A
Claim 3
Dependent Claim
8 words
In the method of cyclizing a compound IA
Claim 4
Dependent Claim
8 words
In the method of cyclizing a compound IA
Claim 5
Dependent Claim
15 words
The method of claim 2 wherein IA is selected so that II is a steroid
Claim 6
Dependent Claim
23 words
The method of claim 2 followed by the step of reductive cleavage of acyl-oxime ether group of II to a glycol group IV
Claim 7
Dependent Claim
29 words
The method of claim 1 wherein the aliphatic nitro compound is a low molecular weight nitro alkane having a primary or secondary carbon atom bonded to the nitro group.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |