Originally macrocyclic compounds capable of assuming a basket (or '
calix') shaped
conformation. They are formed from p-
hydrocarbylphenols and formaldehyde. The term now applies to a variety of derivatives by substitution
of the hydrocarbon cyclo{
oligo[(1,3-phenylene)
methylene]}.
Source:
PAC, 1995, 67, 1307
(Glossary of class names of organic compounds and reactivity intermediates based on
structure (IUPAC Recommendations 1995))
on page 1323