orthonym.validation.spelling.checks_locants

Note

Internal API. Names and behaviour may change between releases.

Spelling checks of locants and numbering,,; registered with orthonym.validation.pin_spelling.register()).

All read the name lexically against the numbering models of:mod:.models; no naming code, no OPSIN.

orthonym.validation.spelling.checks_locants.numbering_check(mol, name)

(:3221) low locants in the order (a) heteroatoms, (b) indicated hydrogen, (c) principal characteristic groups and free valences, (d) added hydrogen, (e) hydro/ene/yne together then double bonds, (f) detachable prefixes together, (g) the prefix cited first. For a unit whose parent’s numbering symmetries are known, the name fails when another numbering is lower at the first point of difference.

The book ranks an element locant against a numeral both ways: italic letters are lower ,:3195,:3215 “N,α,1,2 is lower than 1,2,4,6”), but the PIN ‘N4,2-dimethylpentane-2,4-diamine’ (:26371) is lowest only with numerals first. The check fails a name only when a lower numbering exists under both rankings.

orthonym.validation.spelling.checks_locants.locant_omission_check(mol, name)

(:2877) no terminal locants for acyclic mono- and dicarboxylic acids and their derivatives; (:2891) locant ‘1’ omitted in substituted mononuclear parents and monosubstituted two-atom chains and homogeneous monocycles; (:2939) monosubstituted symmetric parents; (:3007) “All locants are omitted in compounds or substituent groups in which all substitutable positions are completely substituted”; (:3031) acetic acid and parents whose substitutable hydrogens share one locant.

orthonym.validation.spelling.checks_locants.locant_citation_check(mol, name)

(:2869) “if any locants are essential for defining the structure of the parent structure or of a unit of structure as defined by its appropriate enclosing marks, then all locants must be cited for the parent structure or that structural unit. For example, the omission of the locant ‘1’ in 2-chloroethanol… is not allowed in preferred IUPAC names, thus the name 2-chloroethan-1-ol is the PIN”. A unit that cites a numeric locant for a prefix or a hydro prefix but writes its suffix without one, on a carbon chain (other than the mononuclear methane and the acids and their derivatives) or a carbocyclic monocycle; the book writes ‘cyclohexane-1-carboxylic acid’, ‘benzene-1-sulfonic acid’, ‘ethan-1-ol’ beside other locants (:35009,:31174,:28156). And a multiplied simple prefix whose locants do not match its multiplying prefix (‘2-dichloro’, ‘4-dimethylamino’).