Open tylerperyea opened 10 years ago
So enrichment here is a boolean or quantitative value?
It's just boolean. Extent of enrichment is well beyond what is usually captured / capturable with in a single molfile.
Really, the fragment method is just a hack to define a mixture of specific isotopic structures without drawing out each instance. It's somewhat analogous to undefined stereocenters implying a mixture of all wedge / dashes at those sites -- or having a markush structure to define variable substitution on a ring.
I suppose the deeper question here is, is lychi intended to handle mixtures of defined substances at all? And if so, which mixtures?
Certain compounds are isotopically enriched with a specific isotope, but at non-specific atoms. It would be helpful for these to be understood in their most commonly drawn format.
Example 1
Iothalamic acid I-131 CasRN: 770645-97-1 ChemID link: http://chem.sis.nlm.nih.gov/chemidplus/rn/770645-97-1
This structure is how it's shown in ChemID, and represents a typical strategy for capturing isotope enrichment:
Enriched:
Non-enriched:
HASH:
The first fails in standardization, as it contains query / psuedo atoms. However, it is common enough that it should probably be handled. It would ideally produce the same hash as if it were missing the Isotopic enrichment, with a distinct 4th level hash meaning "mixed isotopic enrichment".
Proposed HASH:
Enriched Molfile: