orthonym.rules.bridged_fused_pin

Note

Internal API. Names and behaviour may change between releases.

Bridged fused ring system PINs on every fused parent the engine’s parent tables name with a PIN name (parents.py), in any hydrogenation state, with substituent prefixes, the -ol / -carboxylic acid / -amine / -carbonitrile / -carbaldehyde / -carboxamide suffixes, the -one suffix on a saturated bridge atom, stereodescriptors, and as a ‘-yl’ substituent prefix (slices S1 and S2 of the bridged fused PIN builder); a reading that is a cyclic phane by is declined (slice S2b). Slice S3 (hydro.accommodate): the -one suffix on a ring atom of the fused parent, by indicated hydrogen that accommodates it or by ‘added indicated hydrogen’ (‘1,2,3,7,8,8a-hexahydro-4H-3a,7- methanoazulene-4,9-dione (PIN)’, the Blue Book); cyclic anhydrides, esters and amides of the ring system as pseudoketones, ‘3a,4,7,7a-tetrahydro-1H-4,7-methanoisoindole- 1,3(2H)-dione’); and every other suffix or free valence on an atom with no hydrogen in the mancude parent (‘3,4-dihydro-1,4-methanonaphthalen-1(2H)-ol’).

build(mol) returns the complex-ring tuple (name, ring_atoms, atom_to_locant, True) or None. substituents_included is True: this package spells every prefix, suffix and stereodescriptor itself on its own numbering, because the numbering choice depends on them

(b)-(g), the Blue Book-:3307) and the composer’s complex-ring enrichment adds

prefixes only.

class orthonym.rules.bridged_fused_pin.BridgedParent(hydro, indicated_hydrogen, bridges, base, atom_to_locant, is_pin_form)

Bases: object

The parent hydride of one bridged fused name: ‘1,2,3,4-tetrahydro-1,4-methano’ + ‘naphthalene’. atom_to_locant holds every ring-system atom, bridge atoms too.

hydro: str

indicated_hydrogen: str

bridges: str

base: str

atom_to_locant: Dict[int, Any]

is_pin_form: bool

text(elide=False)

/ (:16872,:16880) and (:14642): hydro prefixes, indicated hydrogen, bridge prefixes, fused parent. (a) (:6938): a hyphen separates the bridge prefix from a parent name that begins with a locant (‘2H,7H-4a,7-ethano-1-benzopyran’,:14648).

orthonym.rules.bridged_fused_pin.MAX_SUFFIX_COUNT = 12

the multiplying prefixes of (Table 1.4), as in ‘benzenehexol (PIN, ‘ (the Blue Book); a bridged fused polyol cites five and more (‘-pentol’), the tetrodotoxin skeleton among them

Type:

the most identical suffixes one name cites

orthonym.rules.bridged_fused_pin.principal_suffix(mol, system)

(‘none’, None, set, set) when the principal characteristic group has no suffix; (‘suffix’, kind, ring atoms, exocyclic suffix atoms) for the suffixes the package spells; None (decline) for any other principal group, or when the group does not sit on the ring system, or when one substituent carries more of it than the ring system : the parent has the maximum number of principal characteristic groups; : a ring is senior to a chain on a tie). A cyclic anhydride, ester, amide or imide of the ring system is a pseudoketone (_pseudoketone_principal): suffix ‘one’. An amidine or guanidine whose carbon is a skeletal atom of the ring system is the ring itself, not a group, and its one exocyclic -NH2, if it has one, is an amine (seniority.ring_skeleton_units_resolved); one with any other exocyclic part declines unless a senior group carries the name.

orthonym.rules.bridged_fused_pin.has_bridged_fused_reading(mol)

True when the largest ring system of mol cannot be named as a fused ring system and (the Blue Book-:14395) selects a reading of it as a bridged fused system whose fused parent the parent tables name (selection.best_splits), whether or not build completes the name (an ester, a bridge prefix the builder does not certify, or a suffix whose indicated or added hydrogen fails the tautomer check or exceeds hydro.MAX_INDICATED_H / hydro.MAX_ADDED_H can still stop it).

(:14241): “When a

polycyclic ring system cannot be named completely as a fused ring system, possible ways for naming it as a bridged fused system are considered”; (:23843): “fused ring systems > bridged fused systems > non-fused bridged systems”. For such a molecule the PIN is a name, never a trivial or name,:50943).

The natural-product route asks this for every molecule it names, so the selection runs under the builder’s error guard (bridged_fused.builder_declining_on_error, as build does): an internal error answers False, logged with its traceback, and the route returns its name as it did before this check existed.

orthonym.rules.bridged_fused_pin.has_unchecked_parent_numbering(mol)

True when a bridged fused reading of mol names a fused parent that OPSIN numbers (parents source ending ‘+opsin’, not a table) and whose skeleton has a tetravalent fusion atom (fusion_components.tetravalent_fusion_atoms, the ‘naphtho[1,8a-b]azirine’ topology of , the Blue Book). Nothing checks such a numbering: the engine’s compute_fused_numbering has no such atom in its grid, so parents._parent_for_key has no second source to agree with OPSIN’s, and fusion_components.periphery_numbering_ok only checks that the locants run round the periphery,:12501). A parent of the tables (the morphinan ‘[1]benzofuro[3,2-e]isoquinoline’, source ‘derived_table’) carries its own numbering. Under the builder’s error guard, as has_bridged_fused_reading: an internal error answers False.

orthonym.rules.bridged_fused_pin.build(mol)

The bridged fused name of mol (whose largest ring system is a nameable fused parent with one to three simple divalent bridges), or None.

orthonym.rules.bridged_fused_pin.build_fused(mol)

The fusion name of mol whose largest ring system is an ortho- or ortho- and peri-fused system with at least two rings of five or more members, in any hydrogenation state, with substituent prefixes and the suffixes principal_suffix spells; the same tuple as build. (the Blue Book) gives such a system the fusion name as its preferred IUPAC name (“When fusion names are not allowed, unsaturated von Baeyer ring system names are preferred IUPAC names”); the hydrogenation is spelled as in build

:16872,:16880,:24766) and the numbering is chosen by (b)-(g) (:3246-:3307). None when the system is not that class or a step declines;

the caller keeps its older path.

orthonym.rules.bridged_fused_pin.build_substituent(mol, attach)

The ‘-yl’ prefix of a bare bridged fused ring system mol (a detached ring system whose free valence is on atom attach, the broken bond left as a hydrogen), or None. (the Blue Book): free-valence locants are “as low as is consistent with any established numbering of the parent hydride”; (:17326): “low locants go first to the fixed numbering of the system, then indicated hydrogen, followed by free valence suffix, and finally ‘hydro’ prefixes” – the free valence takes the place of the suffix in (c) (:3256). Declined: a decorated ring system, a stereocentre, an indicated-hydrogen or hydro atom on or next to a ring nitrogen whose tautomer OPSIN’s reading of the prefix does not share (_same_tautomer_as_radical).

orthonym.rules.bridged_fused_pin.build_fused_substituent(mol, attach)

The ‘-yl’ prefix of a bare fused ring system mol, carbocyclic or heterocyclic (selection.fused_split), whose free valence is on atom attach: the rules and declines of build_substituent.