Figure 1.

Molecular structures and codes of pyrrolo[1,2-a]quinoline derivatives used for their in vitro antifungal activity [44]. All the eight pyrrolo[1,2-a]quinoline derivatives possess common bromo substituents at the fourth position. The four compounds, namely, BQ-01, 03, 05 and 07, consist of methyl ester groups at the second and third positions; in comparison, BQ-02, 04, 06 and 08 possess hydrogen groups at the second position and ethyl esters at third position, respectively. Further, BQ-01, 03, 05 and 07 consist of two ester groups at second and third positions (as highlighted), which donate two electrons, and only one electron donor group present at the third positions of the BQ-02, 04, 06 and 08 derivatives.