|Technical Documentation => Database Development|
of registry numbers is not recommended, however, compounds and
references support registry numbers which are then named MOLNO and REFNO,
A better identification of the compound would be given by using the CAS-RN numbers for compounds and CAS-AN for references.
SciDex has no undo function: be sure to make backup copies before changing sensitive data.
Experiences with external drawing programs:
SciDex is able to do data exchange via clipboard or MOL/SDF-file with most programs.
However, most of the usual chemical drawing programs are optimised for view of the structure, but not for correct definition. For example it happens, that in the drawing program predefined templates of Benzene are instead Heptatriene with two carbon atoms at the same atom co-ordinates.
Other problems can include:
chemical elements are declared as carbon-atoms with a text-label of a different element or even a whole functional group like Ph or NO2, etc...
bonds are not connected to the correct atoms, instead there is an additional carbon atom without label as endpoint of the bond. SciDex will report these as "(very) close atoms".
sometimes the structure can contain non-recognised objects, e.g. parentheses
/ CAS-DR / unspec stereo
CAS Registry Numbers can have the disadvantage that there are "two many" of them.
For example of a compound with one stereo-center, there exists a CAS-RN for the (R) compound, for the (S) compound, another for the racemate and a fourth number which has undefined stereo-chemistry.
Additionally there are CAS-DR numbers (Deleted Registry), which are old and outdated, but sometimes used in older literature.
SciDex has an internal list of many of these numbers and will then assign these automatically to the current CAS-RN. This list in SciDex is far from complete, though.
SciDex Help 1.1
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