US PATENT SUBCLASS 548 / 420
.~.~.~.~ Tetracyclo ring system having the five-membered hetero ring as one of the cyclos


Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use



548 /   HD   ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES

*  DD  ORGANIC COMPOUNDS (Class 532, Subclass 1) {1}
*  DD  .~ HETEROCYCLIC CARBON COMPOUNDS CONTAINING A HETERO RING HAVING CHALCOGEN (I.E., OXYGEN, SULFUR, SELENIUM, OR TELLURIUM) OR NITROGEN AS THE ONLY RING HETERO ATOMS (Class 540, subclass 1) {4}
400  DF  .~.~ Hetero ring is five-membered consisting of one nitrogen and four carbons (e.g., halopyrrolidines, etc.) {20}
416  DF  .~.~.~ Polycyclo ring system having the five-membered hetero ring as one of the cyclos {5}
420.~.~.~.~ Tetracyclo ring system having the five-membered hetero ring as one of the cyclos {3}
421  DF  .~.~.~.~.~> Plural ring hetero atoms in the tetracyclo ring system {2}
424  DF  .~.~.~.~.~> Two of the cyclos share at least three ring members, or a ring carbon is shared by three of the cyclos (e.g., bridged, peri-fused, etc.) {1}
426  DF  .~.~.~.~.~> The five-membered hetero ring shares ring members with one other cyclo only


DEFINITION

Classification: 548/420

(under subclass 416) Compounds wherein the polycyclo ring system consists of exactly four cyclos.