Substituted benzopyrano (3,4-b) pyridines and process for their preparation
Abstract
Abstract In the above formula, R1 and R2 are hydrogen, hydroxy, lower alkoxy or lower alkyl or R1, R2 taken together with the carbon atoms to which they are attached form a methylenedioxy group. In addition, R1 can also be an oxyacetic acid or a derivative thereof, such as an ester, amide or a substituted amide. R3 is hydrogen or hydroxy, R4 is hydrogen or an omega-amino alkyl in which the omega-amino group can be further substituted with one or two alkyl groups or may be a part of a heterocyclic system such as morpholine or imidazoline. In addition, R4 may be an acetic acid or a derivative thereof such as an ester, amide or substituted amide. These compounds are prepared by known reactions. They are useful as bronchodilators. Substituted benzopyrano pyridines having the following structural formula are disclosed:
Inventors
- 👤 Richard E Brown
- 👤 John Shavel Jr
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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