Compounds Containing a N-CO-N or Related Group

Urea and Its Derivatives Rule C-974

974.1 - Compounds formed from urea, isourea, or their derivatives by replacement of oxygen by sulfur, selenium, or tellurium are named by attaching a prefix "thio-", "seleno-", or "telluro-", respectively, directly before urea, ureido-, ureylene-, or uronium. Locants are used in the same way as for urea and its derivatives; when necessary, a locant S, Se, or Te is used to assign substituents to these atoms.

Examples to Rule C-974.1


or 1-Methyl-2-selenourea



When a choice between the two preceding structures cannot be made, the name is: N-Methyl-S-propylisothiourea.

For the above mesomeric cation the name is:


See Recommendations'93 Table 31(a)

Compounds Containing a N-CO-N or Related Group C-975
Compounds Containing a N-CO-N-N or More Complex Group C-981, C-982, C-983, C-984, C-985

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