Substituted benzopyrano[3,4-c]pyridines and process for their preparation
Abstract
Abstract Substituted benzopyrano[3,4-c]pyridines having the following structural formula are disclosed: ##STR1## In the above formula, R 1 R 2 are hydrogen, a hydroxyl group or a lower alkoxyl group of from 1 to 6 carbon atoms; R 3 is hydrogen or a lower alkyl group of from 1 to 6 carbon atoms and X is an oxygen atom, a sulfur atom, a methylene group or a nitrogen atom substituted by hydrogen, a lower alkyl group of from 1 to 6 carbon atoms or a lower alkanoyl group of from 1 to 6 carbon atoms. The compounds of this invention are prepared by reacting an R 1 , R 2 -substituted phenol with a 3-carbethoxy-4-piperidone in the presence of an acid catalyst to give an intermediate R 1 , R 2 -substituted benzopyrano[3,4-c] pyridine. N-aminoalkylbenzopyrano[3,4-c]pyridines are obtained by treating the benzopyrano[3,4-c]pyridine with an appropriately substituted alkyl halide. The compounds of this invention are useful as bronchodilators for the treatment of bronchial asthma.
Inventors
- 👤 Richard E. Brown
- 👤 John Shavel, Jr.
Bibliographic Details
Claims Analysis
Total Claims: 6References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-03-21 | 1980-09-20 | 1981-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-03-21 | 1984-09-20 | 1985-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-03-21 | 1988-09-20 | 1989-03-22 | $7700.00 | Window Closed / Lapsed |