Synthesis of bioactive spiro-2-[3'-(2'-phenyl)-3H-indolyl]-1-aryl-3-phenylaziridines and SAR studies on their antimicrobial behavior

The present communication deals with synthesis of a new series of spiro-2-[3'-(2'-phenyl)-3H-indolyl]-1-aryl-3-phenylaziridines. Infrared (IR), H-1 nuclear magnetic resonance (NMR), mass spectral, and elemental analysis data corroborated the structure of all synthesized compounds. Synthesized compounds were screened for antimicrobial activity against a representative panel of Gram-positive and Gram-negative bacteria. All newly synthesized compounds showed remarkable antimicrobial behavior. Structure-activity relationship (SAR) investigations were applied to investigate the correlation between the molecular refractive index (M-R) parameter of the compounds and their biological activity profile. All compounds were subjected to acute toxicity studies to determine 50% lethal dose (LD50) values.