quasi-enantiomers

Constitutionally different yet closely related chemical species MX and MY having the opposite chirality sense of the large common chiralmoiety M. For example (R)-2-bromobutane is a quasi-enantiomer of (S)-2-chlorobutane.
See also: quasi-racemic compound
Source:
PAC, 1996, 68, 2193 (Basic terminology of stereochemistry (IUPAC Recommendations 1996)) on page 2215