The Hetero Ring Contains Chalcogen Patents (Class 540/544)
- Tricyclo ring system which contains the hetero ring as one of the cyclos (Class 540/547)
- At least three ring hetero atoms in the tricyclo ring system (Class 540/548)
- Sulfur and nitrogen are bonded directly to each other in the hetero ring (Class 540/549)
- The nitrogen of the hetero ring is bonded directly to both remaining rings of the tricyclo ring system (e.g., dibenzo(b,e)(1,4)thiazepine, etc.) (Class 540/550)
- Nitrogen bonded directly to ring carbon of the hetero ring (Class 540/551)
- Bicyclo ring system which contains the hetero ring as one of the cyclos (Class 540/552)