Abstract: wherein R.sub.5, R.sub.6, R.sub.7, R.sub.8 which may be the same or different are selected from the group consisting of H, alkyl of 1 to 5 carbon atoms and halogen; whereinn is an integer of 0 to 5m is an integer of 1 to 10p is an integer of 0 to 1a is an integer of 0 to 1b is an integer of 1 to 10,wherein if a is 1 then b is 1, andwherein the moiety ##STR2## includes at least 5 carbon atoms and wherein D is selected from the group consisting of ##STR3## The compounds may be used as intermediates in the preparation of non-radioactive biological probes.