In the present investigation, a mild, efficient and simple procedure has been developed for the synthesis
of xanthene derivatives is described via three component condensation of aromatic aldehydes with β-
naphthol or dimedone or mixture of β-naphthol and dimedone using Brønsted acidic ionic liquid,
triphenyl(propyl-3-sulphonyl)phosphonium toluene-sulfonate under solvent-free conditions. The
synthesized compounds were screened for antimicrobial activities against Gram-positive (Bacillus subtilis),
Gram-negative (Pseudomonas aeruginosa) bacteria and fungus (Candida albicans). The antioxidant
activities of these compounds were determined by DPPH scavenging free radical method. Present
methodology has a number of advantages such as mild reaction condition, inexpensive catalyst, stable at
room temperature and it was also found that this catalyst might be recovered quantitatively and reused
without much loss of catalytic activity.
