5-substituted pyrazolo[4,3-D]pyrimidin-7-ones
October 21, 2018. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesPyrazolo[4,3-d]pyrimidine-5,7-(4H,6H)dione or -5-thione-7-one analogs 5-Substituted pyrazolo[4,3-d]pyrimidine-7-ones and methods of use Pyrazolopyrimidinone antianginal agents Pyrazolopyrimidinone antianginal agents Pyrazolopyrimidinone antianginal agents Pyrazolopyrimidinone antianginal agents Intermediates useful in the synthesis of pyrazolopyrimidinone antianginal agents 5734053 Process for preparing sildenafil Patent #: 5955611 InventorsApplicationNo. 176166 filed on 10/21/1998US Classes:514/249, 1,4-diazine as one of the cyclos514/228.5, Three or more ring hetero atoms in the polycyclo ring system514/234.5, Plural ring nitrogens in the bicyclo ring system514/250, At least three rings in the polycyclo ring system514/252.02, The additional hetero ring is a diazine514/252.16, Polycyclo ring system having the additional 1,3-diazine ring as one of the cyclos514/262.1, Exactly four ring nitrogens in the bicyclo ring system544/262The other cyclo in the bicyclo ring system is five-memberedExaminersPrimary: Raymond, Richard L.Assistant: Balasubramanian, Venkataraman Attorney, Agent or FirmForeign Patent References
International ClassesA61K 031/519A61P 009/10 A61P 009/12 C07D 487/04 Foreign Application Priority Data1997-10-24 GBAbstractCompounds are disclosed which are useful as PDE1 inhibitors. The compounds have the formula: ##STR1##Other References
Field of SearchThe other cyclo in the bicyclo ring system is five-membered |
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