Steric relations at saturated bridgeheads
common to two rings are denoted by cis
, followed by a hyphen and placed before the name of the ring system, according to
the relative positions of the exocyclic atoms or groups attached to the bridgeheads.
Such rings are said to be cis
-fused or trans
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. https://doi.org/10.1351/goldbook