Class 987 provides an ANCILLARY and totally OPTIONAL search
for subject matter relating to certain types of ORGANIC COMPOUNDS
found under official Class 532. This class has been developed and
relates to the subject matter in Class C07F, subgroups 9/00-19/00
of the International Patent Classification System (IPC).
The subject matter of this class encompasses acyclic, carbocyclic,
or heterocyclic compounds containing elements other than carbon,
hydrogen, nitrogen, sulfur, selenium, tellurium, halogen, and elements
of Groups I-IV of the Periodic System.
This Class Does NOT Provide for Organic Compounds Relating
to:
(1) Peptides, proteins, or enzymes ; (2) Sugars or derivatives
thereof, nucleosides, nucleotides, nucleic acids, saccharides, or
polysaccharides or derivatives thereof; (3) Steroids; (4) Macromolecular
compounds; (5) Dyes.
The Technical Subject Matter of This Class Relates to:
(1) Organic compounds containing a heavy metal of the 6th
to 8th Group of the Periodic System
(2) Organic compounds containing Bismuth, Antimony, or Arsenic
(3) Organic compounds containing Phosphorus
See Subclass References to the Current Class, below, for a
map to these subclasses.
SECTION II - LINES WITH OTHER CLASSES AND WITHIN THIS CLASS
The general hierarchy of the Class 532 series has not been
followed and the above compounds include heterocyclic rings when
present together with the required elements of this class. As can
readily be seen, this class provides an opportunity for searching
certain types of heterocyclic compounds as well as certain phosphorus organic
compounds in an alternative manner from that of Class 532.
Class 987 is a prototypical searching area developed under
the auspices of the Office of International Patent Classification.
In the past, search areas in the U.S. classification system (Classes
976, 968, 984, and 930) have been created utilizing the European
Patent Office"s (EPO) classification of U.S. patents into
their search and retrieval system. Class 987 is significantly different from
those other classification areas in that a substantial number of
patents have been reviewed, a large number of subclasses have been
rearranged or merged, and definitions have been written to describe
the contents of each and every subclass. In addition, the entire
schedule has been presented in a format which utilizes the first place
rule of classification which is the standard practice within the
U.S. Patent Classification System (USPCS).
The European Patent Classification System (EPCS) utilizes,
for the most part, the skeletal outline of the International Patent
Classification System (IPCS). To the broad IPCS, the EPO has added
additional classification areas and thereby has created the EPCS.
These are equatable to alpha subclasses in the USPC. Both the IPCS
and the EPCS utilize a last place classification rule in C07F, which
is the area of classification equatable to new Class 987. The last
place rule requires locating the last subgroup in the classification
schedule which provides for the subject matter to be classified.
The U.S. classification system requires placement in the first subclass
for the subject matter to be classified. As can readily be seen,
these are substantially different philosophies in the placement
of documents. The Class 987 schedule has been presented in a format
which negates this difference and therefor does not place any undue burden
upon the user to learn a new and different philosophy of search.
Class 987 was created with the intention that Group 1200 of
the United States Patent and Office (USPTO) would soon have the
capability of searching patents utilizing all of the enhanced aspects
of the Automated Patent System; in particular, the aspect relating
to image searching. It is the belief of Classification that the
addition of Class 987 to the searchable database can be of assistance
at various times in the examination process.
Although we believe that Class 987 will be of use to the examination
process, we are fully aware that the addition of new search areas
can create problems. One of the most obvious questions that we have
is the question of how examiners in the EPO place documents. In
the USPTO, we know that certain rules exist between classes, that
rules of superiority apply between diverse types of subject matter
(compound, method of making, and method of using), that rules of
comprehensiveness apply between classes, and that all claims are
classified, and unclaimed subject matter is cross-referenced to
subclasses when it is determined to be useful.
In Class 987, we are relying on the placement techniques of
examiners in the EPO to locate U.S. patents. Although we believe
that EPO examiners follow our general rules in the compound classes,
we will not be completely certain until Class 987 is tested and
evaluated by the Corps. We hope to conduct tests in concert with
the Corps and will evaluate fully the effectiveness of Class 987.
If, at the end of the evaluation period, we find that Class 987
does not meet the requirements of the Corps, we will rethink whether
we want to retain the class.
The IPC and the EPC do not contain the types of definitions
associated with U.S. classes. This, in itself, does not in any manner
flaw their system. The titles and attendant notes in the IPC are
the full extent of the content of any subgroup. When those tools
are used together with the Guide to the IPC (Volume 9), all of the tools
to access and retrieval are available. In the creation of this class,
definitions and notes have been written. Many of the definitions
are no more than the repeating of a subclass title, while in other
areas the definitions are much more meaningful. The advantage, of
course, to any definition is that it hopefully conveys information that
the creator of the subclass thought might be useful to a user of
the system and that information is available even if the creator
is no longer available. We believe that the use of definitions leads
to consistency of patent placement.
Class 987 is available on the Automated Patent System (APS).
It is to be treated as any other class, with the proviso that it
cannot accept any original classifications and that any search in
the class is OPTIONAL. Patents can be added through the use of the
blue slip on allowance or by miscellaneous transfer. Patents can
be deleted from the files in the manner currently in use.
Subject Matter Relating to Subclasses 300-304
The subject matter in subclasses 300-304 relates to EPCS 9/02A-9/02E.
This is an ancillary search to subclasses 30-234 which include the
subject matter of this search area, but where no specific subclass
has been identified in that array.
Subject Matter Relating to Subclasses 350-368
The subject matter in subclasses 350-368 which encompasses
phosphorus containing a hetero ring containing at least one nitrogen
atom and no other hetero atom is equivalent in scope to EPCS 9/65-9/65D3B.
The aforementioned area in the EPCS does not accept new patents and
will be abolished in the future. It has been replaced by subgroups
9/547 and 9/553-9/6533 which equate to new
subclass 49 and subclasses 67-108. Although the scope of subject
matter is the same, it has been presented in a different classification
scheme and therefore movement of patents from one area to the other
is not easily done without reading the documents. The EPO is in
the process of reclassifying those patents into their new reclassification
scheme.
It is apparently the policy of the EPO to maintain two searching
areas as patents are being reclassified from an abolished to a newly
created subgroup. Since the abolished area is not equivalent to
the newly established areas, it has been determined by the U.S.
IPC group to concurrently present the two classification systems. When
the EPO has reclassified all of the patents in the abolished area,
the U.S. IPC group will obtain that information and add those patents
to subclasses 49 and 67-108. At the same time, subclasses 350-368
will be abolished.
SECTION III - SUBCLASS REFERENCES TO THE CURRENT CLASS
The following terms are used throughout the schedule.
ARYL
Denotes an independent benzene ring or a benzene ring which
is part of a fused or bridged ring system.
CHALCOGEN
Limited to oxygen (O), sulfur (S), selenium (Se), or
tellurium (Te).
CYANO
Denotes a triple bond between an adjacent carbon and nitrogen
atom. As used in this class, cyano is always bonded directly to
a phosphorus atom through the carbon atom.
CYCLOALIPHATIC
Denotes a ring composed solely of a carbon atom and includes
aryl.
ETHYLENIC
Denotes a double bond or triple between adjacent acyclic
carbon atoms.
HALOGEN
Limited to fluorine (F), chlorine (Cl), bromine (Br), iodine
(I), and astatine (At).
COMPOUND CONTAINS TWO OR MORE HEAVY METAL ATOMS WHICH ARE
IN DIFFERENT GROUPS OF THE PERIODIC SYSTEM (19/00; 19/00B):
This subclass is indented under the class definition. Subject matter wherein the compound contains at least two
different heavy metal atoms which are in different groups of the
Periodic System.
(1)
Note. For purposes of this subclass, the lanthanides (atomic
numbers 57-71) are to be considered as a whole to be in one group
and the actinides (atomic numbers 89 and above) are to be considered
as a whole to be in a separate group. Examples of appropriate placement
in this subclass would be a compound that contained both Fe (Group
8) and As (Group 5) or a compound containing both Fe (Group 7) and
any actinide or lantinide atom.
(2)
Note. A heavy metal is defined as a metal having a specific
gravity greater than four.
(3)
Note. Excluded as heavy metals are the Group 1A and Group
2A metals, with the exception of Ra. Also, excluded are Al and Sc.
Arsenic is considered to be a heavy metal atom in Group 5.
(4)
Note. See the Class 502 schedule (Catalyst, Solid Sorbent,
or Support Therefor: Product or Process of Making) for a grouping
of metal atoms into the appropriate groups of the Periodic System.
HEAVY METAL COMPOUNDS WHEREIN THE METAL IS BONDED DIRECTLY
TO AT LEAST TWO RING SYSTEMS (METALLOCENES) (17/00):
This subclass is indented under the class definition. Subject matter drawn to organic compounds wherein at least
one heavy metal atom is bonded directly to at least two carbocyclic ring
systems or at least two ring systems containing carbon and at least
one atom of nitrogen, oxygen, sulfur, selenium, or tellurium as the
only atoms in the ring or a combination of the above ring systems.
(1)
Note. A heavy metal atom is defined as a metal having a specific
gravity greater then four.
This subclass is indented under subclass 2. Subject matter wherein the heavy metal is a Group 8 metal
atom of the Periodic System (Fe, Co, Ni, Pt, Rh, Pd, Ru, Ir, or
Os).
This subclass is indented under the class definition. Subject matter drawn to carbon compounds wherein cobalt
is bonded directly to a carbon atom or is indirectly bonded to a
carbon atom only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to carbon compounds wherein nickel
is bonded directly to a carbon atom or is indirectly bonded to a
carbon atom only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to carbon compounds wherein iron is
bonded directly to a carbon atom or is indirectly bonded to a carbon atom
only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to carbon compounds wherein platinum
is bonded directly to a carbon atom or is indirectly bonded to a
carbon atom only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to carbon compounds wherein rhodium
is bonded directly to a carbon atom or is indirectly bonded to a
carbon atom only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to carbon compounds wherein palladium
is bonded directly to a carbon atom or is indirectly bonded to a
carbon atom only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to carbon compounds wherein ruthenium
is bonded directly to a carbon atom or is indirectly bonded to a carbon
atom only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to carbon compounds wherein iridium
is bonded directly to a carbon atom or is indirectly bonded to a
carbon atom only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to carbon compounds wherein osmium
is bonded directly to a carbon atom or is indirectly bonded to a
carbon atom only through non-ionic bonding.
COMPOUNDS CONTAINING ELEMENTS OF THE 7TH GROUP OF THE PERIODIC
SYSTEM (Mn, Tc, Re) (13/00):
This subclass is indented under the class definition. Subject matter drawn to organic compounds wherein a Group
7 metal of the Periodic System (Mn, Tc, or Re) is bonded directly to
a carbon atom or is indirectly bonded to a carbon atom only through
non-ionic bonding.
This subclass is indented under subclass 19. Subject matter wherein the compound is devoid of any carbon
atom directly bonded to the group 7 metal atom.
COMPOUNDS CONTAINING ELEMENTS OF THE 6TH GROUP OF THE PERIODIC
SYSTEM (Cr, Mo, W, Po) (11/00):
This subclass is indented under the class definition. Subject matter drawn to organic compounds wherein a Group
6 metal of the Periodic System (Cr, Mo, W, or Po) is bonded either
directly to a carbon atom or is indirectly bonded to a carbon atom
only through non-ionic bonding.
This subclass is indented under subclass 21. Subject matter wherein the compound is devoid of any carbon
atom directly bonded to the group 6 metal atom.
This subclass is indented under the class definition. Subject matter drawn to organic compounds wherein bismuth
is bonded either directly to a carbon atom or is indirectly bonded
to a carbon atom only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to organic compounds wherein antimony
is bonded either directly to a carbon atom or is indirectly bonded
to a carbon atom only through non-ionic bonding.
This subclass is indented under the class definition. Subject matter drawn to organic compounds wherein arsenic
is bonded either directly to a carbon atom or is indirectly bonded
to a carbon atom only through non-ionic bonding.
This subclass is indented under subclass 26. Subject matter wherein a compound contains at least one
atom of arsenic and wherein the arsenic present is not part of a
ring system.
This subclass is indented under subclass 27. Subject matter wherein the arsenic compound contains a ring
system having at least one atom other than metal or carbon as ring
atoms.
This subclass is indented under the class definition. Subject matter drawn to organic compounds wherein phosphorus
is bonded either directly to a carbon or is indirectly bonded to carbon
only through non-ionic bonding.
(1)
Note. In those subclasses which do not recite a valence requirement,
the P atom can be in any valence state.
(2)
Note. Many of the subclasses are presented in a structural
formula recited format. The requirement for this and the indented
subclasses and in the absence to the contrary is that a single moiety
must exist in the compound having the required structure. It is
permissible that the compound contain multiple moieties of the structure,
although in most instances this does not occur or special provision
has been made for those concepts by the creation of subclasses requiring
that feature.
(3)
Note. The following rules apply to the use of structural formulas
or symbols in the schedule or definitions. A structure such as:
(a)
Hal-P-N or (Hal)-P-(N) indicates a direct bond between the
Hal and the P atom and a direct bond between the N atom and the
P atom. Other atoms may be bonded to the P and N atoms. Atoms represented
as being adjacent atoms to each other by a hyphen indicates a direct bond
between those atoms. A hyphen may represent a single, double, or
triple bond.
(b)
P=N or P(=N) indicates a direct double bond
between the P atom and the N atom. Other atoms may be bonded to
the P and N atoms.
(c)
C=X or (C=X) represents a double bond between
a carbon atom and a chalcogen atom and where presented in a structure
indicates a direct bond between the C and the P atom, i.e., P-(C=X)
indicates that a direct bond exists between the C atom of the (C=X)
group and the P atom.
(d)
A single atom between parentheses (any atom) indicates a direct,
e.g., single, double, etc., bond between that atom and a phosphorus
atom, e.g., P-(O) indicates that the bond between the P and the
oxygen atom is direct and not through another atom, and can be a
single or double bond, and P-(C) indicates a direct bond between
P and C and the C can be of any valence, etc.
(e)
A single atom between parentheses (=any atom) indicates
a direct double bond between that atom and a phosphorus atom, i.e.,
P-(=O) indicates that the bond between the P atom and the
oxygen atom is direct and must be a double bond.
(f)
A moiety between parentheses indicates a direct bond between
the moiety and the P. If the moiety is (X-and any other atom) where
S is chalcogen, the direct bond is always between the chalcogen
and the P atom, unless there exists a double bond between the X
atom and the other required atom, i.e., C=X in which case
the direct bond is between the C and the P atom.
(g)
Chemical moieties shown without parenthesis with the exception
of moieties shown between quotation marks "--" (see
(h) below) cannot be bonded directly to the required P atom. Furthermore,
they may or may not be directly bonded to the adjacent indicated
atom.
(h)
Chemical moieties shown between quotation marks "--" indicates
that an atom of the group, e.g., "ethylenic group," indicates
that a carbon of the ethylenic group can be directly or indirectly
bonded to a P atom and "carbocyclic ring" indicates
that a carbon atom of the carbocyclic ring can be directly or indirectly
bonded to the P atom, etc.
(i)
The term "Q" indicates a moiety containing
an atom other than C or H. The particular atom that is other than
C or H may or may not be bonded directly to the adjacent atom shown.
The bonding to the adjacent atom shown cannot be through a phosphorus
atom and requires a bond other than ionic.
(j)
X used throughout the schedule and definitions is limited
to chalcogen, i.e., Oxygen (O), Sulfur (S), Selenium (Se), and Tellurium
(Te). For ease of readability, in many instances, the chemical symbols
for these elements have been used.
(k)
Phosphorus and its chemical symbol (P), carbon and its chemical
symbol (C), nitrogen and its chemical symbol (N), and hydrogen and
its chemical symbol (H) have been used interchangeably throughout
the schedule and definitions.
(l)
Halogen or its abbreviated form (Hal) has been used throughout
the schedule or definitions to indicate the presence of fluorine,
chlorine, bromine, iodine, or astatine atoms.
(m)
The term "Z" indicates an atom other than
C or H and requires a direct non-ionic bond between the particular
atom that qualifies as Z and the adjacent atom indicated. The term
is meant to exclude classification on the inorganic portion of an
organic phosphorus containing compound. See (q) below.
(n)
Chemical moieties shown within parentheses and an asterisk
(*). (1) (Aryl*) indicates that a carbon of the aryl
ring is bonded to the adjacent indicated atom shown. (2) (Carbocyclic*) indicates
a ring atom of the carbocyclic is directly bonded to the adjacent
indicated atom shown. (3) (Ethylenic*) indicates a carbon
of the unsaturated group (double or triple bond) is directly bonded to
the adjacent atom shown. (4) (Cyano*) indicates a direct
bond between the carbon of the cyano group and the adjacent atom
shown. (5) (Acyl*) indicates a direct bond between the
carbon of the acyl group and the adjacent group shown.
(o)
A moiety interposed between quotation marks "--" indicates
that it is alternative as to whether the named group is directly
or indirectly bonded to the P atom.
(p)
Bonded directly or directly bonded indicates a non-ionic bond
between the two adjacent required atoms or moieties.
(q)
Indirectly bonded or bonded indirectly indicates a nondirect,
non-ionic, linkage between nonadjacent atoms or moieties. The terms
are used to exclude classification on the inorganic portion of a
salt. When a compound is composed of both an organic cation and
an organic anion, then classification on both of the organic moieties
is appropriate.
(4)
Note. Organic acid salts, alcoholates, phenates, chelates,
or mercaptides are classified on the basis of the organic portion
of the compound that contains the phosphorus atom. If both the anion
and cation are organic, the entire molecule is classified.
This subclass is indented under subclass 30. Subject matter wherein a ring contains at least one atom
other than C, N, O, S, P, Se, or Te as ring members.
This subclass is indented under subclass 30. Subject matter wherein a phosphorus atom is part of a ring.
(1)
Note. When phosphorus is a ring member, the traditional definition
of "heterocyclic" atom, as used throughout the Class
532 series, is not met. Furthermore, the definition of "heterocyclic," in the
532 series, requires the presence of a carbon atom as a ring member,
this is not the situation in the EPC.
(2)
Note. Whenever a ring atom is used throughout this and its
indented subclasses, it is meant to include only those additional
atoms that are in the same ring as is phosphorus. An example of
this is subclass 46, the oxygen ring atom must be in the same ring
with the P atom.
(3)
Note. Extracyclic, as used in this and its indented subclasses,
is meant to include atoms not in the same ring as phosphorus. A
non-ring atom would include a heterocyclic ring containing that
atom in a ring devoid of phosphorus and other ring atoms required
by the title of the subclass.
This subclass is indented under subclass 33. Subject matter wherein a ring contains (a) N and P atoms
only or (b) N and P and additional atoms only of C, S, or O.
(1)
Note. All of the additional possible atoms need not be present.
This subclass is indented under subclass 33. Subject matter wherein a ring contains (a) S and P atoms
or (b) S and P and additional atoms of C or O only.
(1)
Note. All of the additional possible atoms need not be present.
This subclass is indented under subclass 33. Subject matter wherein the ring contains only phosphorus
and oxygen atoms or phosphorus and oxygen and additional atoms only
of carbon.
This subclass is indented under subclass 37. Subject matter wherein a phosphorus atom is bonded directly
to at least two oxygen atoms and wherein the phosphorus atom is
shared by two separate rings and the two oxygen atoms are in different
ring systems or are shared by two ring systems.
(1)
Note. An example of a compound classified herein is:
This subclass is indented under subclass 37. Subject matter wherein the phosphorus in the ring is bonded
solely to oxygen atoms in the ring and solely to oxygen atoms extracyclic
to the ring.
This subclass is indented under subclass 39. Subject matter wherein (a) the compound contains at least
two phosphorus atoms in different rings and the two phosphorus atoms
are bonded solely to oxygen or (b) wherein a single ring contains
at least two phosphorus atoms and all bonds to at least two of the
phosphorus atoms are solely to oxygen.
This subclass is indented under subclass 39. Subject matter wherein the phosphorus containing ring shares
at least two carbon atoms of a carbocyclic ring or taken together
with two or more carbocyclic rings forms a ring therewith.
(1)
Note. An example of a compound appropriate for this subclass
is:
This subclass is indented under subclass 37. Subject matter wherein the ring phosphorus atom is bonded
directly to at least one oxygen atom in the ring and is also bonded
to at least one nitrogen atom which may be in the ring or extracyclic
to the ring.
This subclass is indented under subclass 37. Subject matter wherein the ring phosphorus atom is bonded
to a carbon which may be part of the ring or extracyclic to the
ring.
This subclass is indented under subclass 37. Subject matter wherein the ring phosphorus atom is bonded
directly to a sulfur atom, the sulfur being extracyclic to the phosphorus
containing ring.
This subclass is indented under subclass 46. Subject matter wherein (a) the compound contains at least
two phosphorus atoms in different rings and the two phosphorus atoms
are bonded directly to ring oxygen and extracyclic sulfur or (b)
wherein a single ring contains at least two phosphorus atoms and
each of the phosphorus atoms is bonded directly to ring oxygen and
extracyclic sulfur.
This subclass is indented under subclass 46. Subject matter wherein the phosphorus containing ring shares
at least two carbon atoms of a carbocyclic ring or taken together
with two or more carbocyclic rings forms a ring therewith.
(1)
Note. An example of a compound appropriate for this subclass
is:
This subclass is indented under subclass 30. Subject matter wherein the phosphorus compound contains
at least one hetero atom (i.e., oxygen, sulfur, nitrogen, selenium
or tellurium) as a ring member, and wherein the ring may or may
not contain carbon.
(1)
Note. Compounds herein are not required to have carbon atoms
as ring atoms. Compounds which are devoid of a carbon atom as a
ring member are not in fact "heterocyclic compounds" as used
throughout the Class 532 series. In those instances where the ring
does contain at least one atom of carbon the term is identical in
usage to the Class 532 series. When the term "heterocyclic ring" is
used in this class, it does in fact conform to the Class 532 definition.
(2)
Note. Included specifically in this subclass are rings containing
four or more nitrogen atoms.
(3)
Note. The rule to be followed in those compounds containing
multiple rings having an atom other than carbon as ring members
is that classification is made on the ring nearest to the phosphorus
atom. It is desirable, however, if classifications are assigned
for each of the rings.
This subclass is indented under subclass 49. Subject matter wherein the P compound (a) contains two or
more ring systems, each of which contains an atom other than C as
a ring member, and wherein at least two of the rings share two or
more of their ring atoms together, or (b) where a common carbocyclic
ring or ring system shares two or more of its carbon atoms with
each of the required rings.
This subclass is indented under subclass 49. Subject matter wherein the P compound (a) contains at least
two different ring systems, each of which contains at least one
atom other than carbon, or (b) where a compound contains a plurality
of identical rings, each of which contains at least one atom other
than carbon and wherein the substituents on at least two of the
identical ring systems are different.
This subclass is indented under subclass 54. Subject matter wherein the phosphorus compound contains
at least one heterocyclic ring which is devoid of a nitrogen atom
as a ring member.
This subclass is indented under subclass 49. Subject matter wherein the phosphorus compound (a) contains
at least one ring having only sulfur, per se, as a ring member or
(b) contains a ring having at least one atom of sulfur and additional
ring atoms of only carbon, selenium, or tellurium.
This subclass is indented under subclass 56. Subject matter wherein a ring containing both sulfur and
carbon atoms shares at least two of its carbon atoms with a ring
system containing only carbon atoms.
This subclass is indented under subclass 49. Subject matter wherein the phosphorus compound contains
at least one ring which contains only oxygen and carbon atoms, or
oxygen and carbon and additional atoms of only sulfur, selenium,
or tellurium.
This subclass is indented under subclass 58. Subject matter wherein the ring containing the oxygen atom
shares at least two of its carbon atoms with a ring system containing
only carbon atoms.
This subclass is indented under subclass 49. Subject matter wherein the ring contains (a) only atoms
of sulfur and nitrogen or (b) only atoms of sulfur, nitrogen, and
carbon or (c) oxygen, selenium, or tellurium as the sole additional
atoms in a ring of (a) or (b) above.
This subclass is indented under subclass 63. Subject matter wherein a ring containing the nitrogen, sulfur
and carbon atoms shares at least two of its carbon atoms with a
ring system containing only carbon atoms.
This subclass is indented under subclass 49. Subject matter wherein the ring contains (a) only atoms
of nitrogen and oxygen or (b) only atoms of nitrogen, oxygen, and
carbon.
This subclass is indented under subclass 68. Subject matter wherein the six-membered ring shares at least
two of its ring carbon atoms with a ring system containing only
carbon atoms.
This subclass is indented under subclass 68. Subject matter wherein at least one of the carbon atoms
of the six-membered ring is (a) bonded directly to an extracyclic
phosphorus atom or (b) is bonded directly to an extracyclic hetero
atom other than nitrogen, and which hetero atom is directly bonded
to an extracyclic phosphorus atom.
This subclass is indented under subclass 71. Subject matter wherein the five-membered ring shares at
least two of its ring carbons with a ring system containing only
carbon atoms.
This subclass is indented under subclass 71. Subject matter wherein at least one of the carbon atoms
of the five-membered ring is (a) bonded directly to an extracyclic
phosphorus atom or (b) is bonded directly to an extracyclic hetero
atom, other than nitrogen, and which hetero atom is
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