orthonym.rules.bridged_fused_pin.hydro#
Note
Internal API. Names and behaviour may change between releases.
Hydrogenation state of a bridged fused ring system: mancude parent, indicated hydrogen, hydro prefixes.
(the Blue Book): “The maximum number of noncumulative double bonds is
assigned to the fused ring system after the insertion of the bridge.” (:14583): “In bridged fused systems, the distribution of noncumulative double bonds in the parent fused ring system is accomplished after allowance has been made for the bonds existing between the bridge(s) and the fused ring system.” So the mancude parent is a maximum matching over the parent atoms that keep a free valence after the bridge bonds (a fusion atom that carries a bridge has four ring bonds and no double bond, as 4a and 8a of 4a,8a-ethanonaphthalene); the atoms the matching leaves out carry indicated hydrogen, “cited in front of the completed bridged fused ring name” (:14245;:14642 “All indicated hydrogen atoms are indicated at the front of the complete name”).
(:16880): hydro prefixes come in pairs, “Indicated hydrogen atoms have priority
over ‘hydro’ prefixes for low locants. If indicated hydrogen atoms are present in a name, the ‘hydro’ prefixes precede them.” (:17026): “Total hydrogenation is indicated by the appropriate multiplicative prefixes indicating the total number of hydrogen atoms attached, but locants are omitted”.
- orthonym.rules.bridged_fused_pin.hydro.MAX_INDICATED_H = 2#
at most this many indicated-hydrogen positions (slice S1)
- class orthonym.rules.bridged_fused_pin.hydro.HydroState(eligible: FrozenSet[int], saturated: FrozenSet[int], n_double: int, mancude_double: int, ih_sets: Tuple[FrozenSet[int], ...])#
Bases:
object- eligible: FrozenSet[int]#
- saturated: FrozenSet[int]#
- n_double: int#
- mancude_double: int#
- ih_sets: Tuple[FrozenSet[int], ...]#
- orthonym.rules.bridged_fused_pin.hydro.hydro_state(mol, split)#
- orthonym.rules.bridged_fused_pin.hydro.choose_indicated_hydrogen(state, atom_to_locant)#
(indicated-hydrogen atoms, hydro atoms) under this numbering. (the Blue Book): indicated hydrogen is cited “if posible, at the lowest nonfusion peripheral atom”, also when hydro prefixes are present (:24685 ‘3a,5-dihydro-4H-indene (PIN) (not 4,5-dihydro-3aH-indene)’); among the allowed sets, the fewest fusion atoms, then the lowest locants:16880).
- orthonym.rules.bridged_fused_pin.hydro.hydro_text(state, hydro_atoms, atom_to_locant)#
‘’ (mancude), ‘1,2,3,4-tetrahydro’, or ‘decahydro’ for total hydrogenation.
- orthonym.rules.bridged_fused_pin.hydro.ih_text(ih_atoms, atom_to_locant)#
‘’ or ‘1H’ or ‘2H,7H’.