1.2 Cyclic Systems
Dispiro [cyclopenta[ 1,2-b: 4,3-b'j dipyridine9,2' -thiirane-3',9" -fluorene j
6,6' -Spirobi[ dibenzo[d,fj [1,3,2jdioxagermepine j
65
Fused heterocyclic systems containing additional hydrocarbon bridges
are again treated like their carbocyclic anlogues. If, on the other hand, hetero bridges occur in such compounds, they are expressed as composite prefixes to the name in the following way: the front term ep{i) is succeeded by
the hetero symbols according to the "a"-term table with a terminal "0"
instead of "a" (which is elided when followed by a vowel). In unambiguous
cases ep(i) can be ommitted. (Beilstein, however, always uses this front
term if it does not switch over to totally systematic formats, as shown in
the following examples).
-N=N-NH- Azimino (new: triaz[ljeno), -N=N- Azo (diazeno),
- NH - NH - Biimino (diazano)
-NH- Imino (epimino,epiazano),-N= Nitrilo (azeno),-N::::::: Azanetriyl
etc., -PH- Phosphano etc., -SiHz- Silano etc.
-0-, -S- Epoxy, epithio (but: -SHz- ,V-Sulfano etc.); -S-S- Epidithio;
-O-S- Epoxythio; -s-o-NH - Epithioximino;
-Se-O-Te- Episelenoxytelluro;
-O-{ CHz)n- Epoxyalkano; -O-{ CHz)n-S- Epoxyalkanothio;
-S-( CHz)n-N = Epithioalkanonitrilo;
-( CHz)n-O-{ CHz)n- Alkanoxyalkano;
4
1,4-Dihydro-I,4-( epoxymethano )isobenzofuran
Beilstein: ... oxaethano ...