Fig. 4 in Phaeosphspirone (1/1 ), a pair of unique polyketide enantiomers with an unusual 6/5/5/6 tetracyclic ring from the desert plant endophytic fungus Phaeosphaeriaceae sp.

Fig. 4. Δδ values (in ppm) = δS - δR for (R)- and (S)-MPTA diesters 1a/1b and 1′a/1′b.