C07D 221/18
Ring systems of four or more rings
C07D221/18 (Ring systems of four or more rings) appears on 459 US grants and 437 published applications in this corpus.
Search patents in C07D- Granted patents
- 459
- Published applications
- 437
- Assignees
- 303
- Inventors
- 1,273
- Latest grant
- 22 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 5 | 0 |
| 1977 | 8 | 0 |
| 1978 | 5 | 0 |
| 1979 | 6 | 0 |
| 1980 | 2 | 0 |
| 1981 | 7 | 0 |
| 1982 | 6 | 0 |
| 1983 | 1 | 0 |
| 1984 | 2 | 0 |
| 1985 | 2 | 0 |
| 1986 | 3 | 0 |
| 1987 | 1 | 0 |
| 1988 | 2 | 0 |
| 1989 | 3 | 0 |
| 1990 | 5 | 0 |
| 1991 | 4 | 0 |
| 1992 | 6 | 0 |
| 1993 | 6 | 0 |
| 1994 | 6 | 0 |
| 1995 | 5 | 0 |
| 1996 | 3 | 0 |
| 1997 | 19 | 0 |
| 1998 | 14 | 0 |
| 1999 | 11 | 0 |
| 2000 | 12 | 0 |
| 2001 | 4 | 0 |
| 2002 | 7 | 5 |
| 2003 | 12 | 12 |
| 2004 | 10 | 27 |
| 2005 | 7 | 12 |
| 2006 | 13 | 22 |
| 2007 | 11 | 12 |
| 2008 | 7 | 18 |
| 2009 | 9 | 20 |
| 2010 | 19 | 26 |
| 2011 | 17 | 27 |
| 2012 | 10 | 15 |
| 2013 | 18 | 20 |
| 2014 | 12 | 28 |
| 2015 | 25 | 22 |
| 2016 | 18 | 23 |
| 2017 | 16 | 27 |
| 2018 | 11 | 21 |
| 2019 | 17 | 13 |
| 2020 | 14 | 12 |
| 2021 | 15 | 17 |
| 2022 | 12 | 15 |
| 2023 | 9 | 18 |
| 2024 | 5 | 7 |
| 2025 | 9 | 12 |
| 2026 | 8 | 6 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Dopamine receptor d1 agonists and methods of use22 Sep 2026US 12,741,940 B2Mayo Foundation for Medical Education and Research
- Calixarene compounds and uses thereof25 Aug 2026US 12,714,682 B2Universität Wien
- Oxynitidine derivatives useful as inhibitors of topoisomerase IB (TOP1) and tyrosyl-DNA phosphodiesterase 1 (TDP1)16 Jun 2026US 12,655,107 B2Shenzhen Xuhua Biotech Co. Ltd.
- Rylene dicarboximides2 Jun 2026US 12,643,862 B2BASF SE
- Light emitting element and amine compound for the same2 Jun 2026US 12,648,351 B2Samsung Display Co., Ltd.
- Light emitting element and amine compound for the same3 Sep 2026US 2026/0262446 A1Samsung Display Co., Ltd.
- Regio-controllable [2+2] benzannulation with two adjacent c(sp3)-h bonds20 Aug 2026US 2026/0242341 A1The Scripps Research Institute
- Aromatic compounds for organic electroluminescent devices16 Jul 2026US 2026/0200952 A1UDC Ireland Limited
- Compound, composition, cured product, method for producing cured product, and method for producing electronic component28 May 2026US 2026/0146026 A1Adeka Corporation
- Bicyclic pyridine derivative5 Feb 2026US 2026/0035379 A1Sumitomo Pharma Co., Ltd.
Most cited
By later US patents
- Substituted heterocycle fused gamma-carbolines138US 6,552,017 B1Bristol-Myers Squibb Pharma Company · 2003
- Substituted heterocycle fused gamma-carbolines131US 6,548,493 B1Bristol-Myers Squibb Pharma Company · 2003
- Steroid receptor modulator compounds and methods128US 5,696,127 ALigand Pharmaceuticals Incorporated · 1997
- Substituted heterocycle fused gamma-carbolines122US 6,713,471 B1Bristol-Myers Squibb Pharma Company · 2004
- Steroid receptor modulator compounds and methods120US 5,688,810 ALigand Pharmaceuticals Incorporated · 1997