In summary: The OFG profile is currently subdivided into OFG (general) and OFG (nested), which include the same functional groups. The difference is that OFG (general) displays all functional groups present in the target compounds, while the OFG (nested) do not show the functional groups which are nested in the larger ones (i.e. aldehyde group is nested in carboxylic group and it is not shown with OFG (nested) profiler). Thus any “overlapping” groups in the OFG (nested) system actually form new functional groups.
In details: The OFG (nested) profiler includes the same list of organic functional groups as in the OFG profiler. The differences here is that once the chemical is profiled and all functional groups are identified for the current chemical to provide the user the most common group, which completely covers all the nested ones. Here the nested functional groups are skipped. Below is provided an illustration of such example (see Fig.1).
Fig 1. Illustration of an example for discrepancy between OFG and OFG (nested)
The current example chemical as seen include three functional groups identified by OFG profilers: Aminoaniline meta; Aniline and Aryl. As you already know OFG provide all the three once, however in OFG (nested) the two nested groups: Aniline and Aryl are skipped and only the most common (general) group is provided to the user ONLY. Please see the snapshot from TB 3.4:
Fig. 2 Snapshot of profling result for CAS 541-69-5 obtained by OFG and OFG (nested) profilers.
In addition to this if there are some overlap between groups a new category called ”overlapping groups” is generated providing the user possibility to perform a category based on this new one.
A simple example is provided on Fig.3, below. Once you profile the target chemical, perform right click over the cell with profiling result (1), then click over “overlapping groups” category (2) and ask for Details(3). A new window appears and if you click over a label “1x1 &1x2 “ (4) and move the scroller (5) you will see how the both groups overlapped each other.
Fig.3 illustration of overlapping group details