The title Schiff base, C(17)H(15)N(3)O(3), exists in the zwitterionic form with the phenol H atom transferred to the imine group. Adjacent zwitterions are linked into a linear chain running along the a axis by an indole-hydr-oxy N-H⋯O hydrogen bond [3.100 (2) Å].
* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.