Term: preferred constitutional repeating unit
https://doi.org/10.1351/goldbook.09016
Definition:
Constitutional repeating unit (CRU) written with the subunits in a linear series from the highest (higher) seniority to the lowest (lower) or as close as possible by the shortest path.
Notes:
1) This definition is based on descriptions of methods to reach the P-CRU.
2) The P-CRU is chosen with the lowest possible locant(s) for the substituents.
Examples:
1) \(\ce{-[O-CH2CH2-S-CH2CH2]_{n}\bond{-}}\ \rm{not}\ \ce{-[S-CH2CH2-O-CH2CH2]_{n}\bond{-}}\)
2) \(\ce{-[O-CH2CH2-O-CH2CH2CH2]_{n}\bond{-}}\ \rm{not}\ \ce{-[O-CH2CH2CH2-O-CH2CH2]_{n}\bond{-}}\)
Examples:
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<h5>Version 3.0.1 (8045 Terms)</h5>
<code>DOI: 10.1351/goldbook</code>
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<a href="mailto:goldbook@iupac.org?subject=Gold Book Content Question">Jan Kaiser - Content Editor</a><br/>
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