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CPC Subgroup
A61K 31/4353

ortho- or peri-condensed with heterocyclic ring systems

Full Title

Medicinal preparations containing organic active ingredients > Heterocyclic compounds > having nitrogen as a ring hetero atom, e.g. guanethidine or rifamycins > having six-membered rings with one nitrogen as the only ring hetero atom > ortho- or peri-condensed with heterocyclic ring systems

5 direct subcodes

Child Classifications

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  • A61K 31/4355 the heterocyclic ring system containing a five-membered ring having oxygen as a ring hetero atom
  • A61K 31/436 the heterocyclic ring system containing a six-membered ring having oxygen as a ring hetero atom, e.g. rapamycin
  • A61K 31/4365 the heterocyclic ring system having sulfur as a ring hetero atom, e.g. ticlopidine
  • A61K 31/437 the heterocyclic ring system containing a five-membered ring having nitrogen as a ring hetero atom, e.g. indolizine, beta-carboline
  • A61K 31/4375 the heterocyclic ring system containing a six-membered ring having nitrogen as a ring heteroatom, e.g. quinolizines, naphthyridines, berberine, vincamine

Top Applicants

Top 10 applicants by patent filingsfor class A61, 2013–2023, worldwide · Source: EPO PATSTAT

  1. PHILIPS ELECTRONICS NL 20,621
  2. NOVARTIS CH 15,792
  3. ROCHE CH 14,303
  4. COVIDIEN US 13,862
  5. HARVARD UNIVERSITY US 13,454
  6. UNIVERSITY OF CALIFORNIA US 12,798
  7. P&G (PROCTER & GAMBLE COMPANY) US 12,140
  8. L'OREAL FR 11,800
  9. OLYMPUS CORPORATION JP 9,894
  10. BOSTON SCIENTIFIC SCIMED US 9,513