Table 1. Antibacterial activities of 1 (0.25 μmol) and its C-7 F- and Cl-substituted analogues 1e (0.25 μmol) and 1h (0.25 μmol) against V. cholerae, E. coli and B. subtilis, assessed by disc diffusion agar assay.

Compound	lnhibition zone diameter (mm)
	V. cholerae	E. coli	B. subtilis
1a	19	38	29
1e	19	36	31
1h	20	39	31