A cyclic molecule is one like benzene that forms a ring. Macrocyclics are larger rings sometimes made from rings of rings. A simple example is the crown ether which is (CCO)n like C1O CCO CCO CCO CCO CCO C1 (gaps deliberately included). These structures can get as complicated as the skill and time of the chemist making them.

Other examples:

• Cryptand
• Spherand
• Carcerand
• Calixarene
• Cyclodextrin
• Sepulchrate