orthonym.rules.bridged_fused_pin.prefixes

Note

Internal API. Names and behaviour may change between releases.

Bridge prefixes and their citation: simple divalent bridges and the one composite bridge OPSIN 2.9.0 reads, ‘(epoxymethano)’.

(the Blue Book): “A divalent acyclic hydrocarbon bridge is named as a

prefix derived from the corresponding unbranched hydrocarbon name by changing the final letter ‘e’ to ‘o’.” with the preferred prefixes ‘-CH2- methano’, ‘-CH2-CH2- ethano’, ‘-CH2-CH2-CH2- propano’, ‘-CH=CH- etheno’. (:14095-:14110): ‘-O-’ is ‘epoxy’ (a preselected prefix); the preselected prefixes of ‘-S-’, ‘-S-S-’ and ‘-NH-’ are ‘sulfano’, ‘disulfano’ and ‘azano’; ‘epithio’, ‘epidithio’ and ‘epimino’ are general nomenclature, so a name that carries one is recorded as not a PIN (bridged_fused.GENERAL_ONLY_BRIDGE_PREFIXES). A default-tier call spells the preselected prefixes (twin_spellings.pin_spellings_on); OPSIN 2.9.0 has no grammar for them, so the validity gate reads the name through its twin spelling (validation.twin_spellings). A wider tier spells the general prefixes, which OPSIN reads. A prefix cited more than once is spelled in the general form at both tiers: ‘disulfano’ names the -S-S- bridge, so it cannot stand for two -S- bridges.

(:14173): “If there is more than one bridge, they are cited in alphabetical

order… Two or more identical bridges are indicated by the numerical prefixes ‘di’, ‘tri’, etc. with simple bridges… The locant pairs of identical bridges are separated by colons.” (:14181): the locants of a divalent symmetric bridge “are cited in numerical order”.

class orthonym.rules.bridged_fused_pin.prefixes.BridgePrefix(name, is_pin_form, first=None)

Bases: object

first is the bridgehead whose locant is cited first: None for a symmetric bridge

:14181, “cited in numerical order”), else the bridgehead bonded to the

first atom of the bridge name:14201, “in the order expressed or implied by the name of the bridge”): the O of ‘(epoxymethano)’, C1 of ‘prop[1]eno’.

name: str

is_pin_form: bool

first: int | None = None

orthonym.rules.bridged_fused_pin.prefixes.multiplied_in_general_form(bridges)

bridges with every preselected prefix that is cited more than once spelled in the general form (see the module doc).

orthonym.rules.bridged_fused_pin.prefixes.bridge_prefix(mol, split, i)

The prefix of bridge i of split, or None for a bridge this package does not spell (a ring bridge, a composite other than ‘(epoxymethano)’, a charged or radical atom, a nonstandard valence, an unsaturated chain the Blue Book lists no prefix for). Unsaturation is read from split.unsaturated (the ring double bonds of the input, independent of the Kekule structure RDKit picks).

orthonym.rules.bridged_fused_pin.prefixes.citation_key(prefix)

Alphanumerical order of bridge prefixes:14173), parentheses ignored.

orthonym.rules.bridged_fused_pin.prefixes.bridge_text(cited)

‘1,4-epoxy-4a,8a-ethano’, ‘1,4:5,8-dimethano’: groups of identical prefixes in alphabetical order, each group’s locant pairs ascending and joined by colons. Two identical composite bridges would need ‘bis’, which OPSIN 2.9.0 cannot read: None.

orthonym.rules.bridged_fused_pin.prefixes.bridge_prefix_words()

Every bridge prefix this package spells or reads: the producer’s tables, the lexicon of the reader of names (validation/spelling/units.py, which also holds the composite prefixes), the general nomenclature prefixes and the prefixes of the book no table holds (_BRIDGE_WORDS_OF_THE_BOOK).

orthonym.rules.bridged_fused_pin.prefixes.ends_in_bridge_prefix(text)

True iff text ends in a bridge prefix cited with its locants (’…-7,14-methano’, ‘3,5-(epoxymethano)’, ‘4a,8a-di(metheno)’, ‘1,2-prop[1]eno’): a name part that opens at the end of text is the fused system the bridge belongs to,:14046: the bridge prefixes are cited in front of the fused system’s name). A word that is a bridge prefix or built on ‘epi’; ‘dihydro’, ‘dimethyl’ and the other substituent prefixes are not, and a single locant is not a bridge.