Start with a fused indole system comprising a benzene ring fused to a pyrrole ring. Number the peripheral atoms of the fused system (excluding the atoms shared by both rings) by designating the pyrrole nitrogen as position 1 and proceeding sequentially around the system. This numbering yields N1-C2-C3 in the pyrrole ring, followed by C4-C5-C6-C7 in the benzene ring.
At position C3 of the pyrrole ring, the structure is extended by a phenyl ring bearing a chlorine substituent at the para position relative to the point of attachment (a p-chlorophenyl substituent).
The benzene ring of the fused system carries three substituents:
- Two methoxy groups (-OCH3) at positions C4 and C6.
- On C7, a di-carbonyl substituent (-C(=O)-C(=O)-): the point of attachment to the indole ring is a carbon doubly bonded to oxygen and singly bonded to another carbonyl bearing a morpholine ring on its nitrogen. Put differently, this second carbonyl is part of an amide in which the amide nitrogen is the nitrogen of a saturated six membered ring containing a nitrogen and an oxygen in a para arrangement.