EP Patent

EP0812845A1 — Process for preparing sildenafil

Assigned to Pfizer Ireland Pharmaceuticals · Expires 1997-12-17 · 28y expired

What this patent protects

A process for the preparation of a compound of formula (I): also knows as sildenafil which comprises cyclisation of a compound of formula (II):

USPTO Abstract

A process for the preparation of a compound of formula (I): also knows as sildenafil which comprises cyclisation of a compound of formula (II):

Drugs covered by this patent

vardenafil-hydrochloride (VARDENAFIL HYDROCHLORIDE)

Patent Metadata

Patent number: EP0812845A1
Jurisdiction: EP
Classification: —
Expires: 1997-12-17
Drug substance claim: No
Drug product claim: No
Assignee: Pfizer Ireland Pharmaceuticals
Source: FDA Orange Book + USPTO grounding via Google Patents

Bibliographic data sourced from FDA Orange Book + USPTO public records. Plain-English summary generated by AI grounded in source text. Patent term extensions (PTR, SPC, pediatric) may shift the effective expiry. Not legal advice.

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