Background: Plethora of literature reported hitherto, depicts impending biological activities
for spirochromones. This fact encouraged us for the exploration of the synthesis of new
substituted spirochromones and their evaluation of their bioactivities.
Objectives: To synthesize different substituted spirochromones derivatives from a spirochromones salt
using (R)-pyroglutamic acid as catalyst and their evaluation for antimicrobial and antioxidant activities.
Methods: Herein, Aldol cascade method was used for the syntheses of spirochromone derivatives
from its salt. A mild protocol is developed for the syntheses of spirochromones derivatives by using
(R)-pyroglutamic acid as catalyst. Further, the derivatives and its precursor salt were screened
for antimicrobial and antioxidant activity. The antioxidant potentials of the synthesized compounds
were checked by DPPH and hydroxyl free radical scavenging assay. Consequently, in vitro antimicrobial
activities were performed by well diffusion assay against gram negative bacterium (E.
coli) and gram positive bacterium (S. aureus).
Results: In the present work, 10 synthesized derivatives are obtained in harmonious yield from a
precursor spirochromones salt using (R)-pyroglutamic acid as catalyst. Amongst the studied compounds,
6a depicted maximum antimicrobial activity against the screened microorganisms along
with maximum antioxidant activity. Albeit, the synthesized motifs showed moderate to good antioxidant
and antimicrobial activities.
Conclusion: A mild protocol was developed for the synthesis of spirochromone derivatives from
their precursor spirochromones salt by using (R)-pyroglutamic acid as catalyst, which showed
moderate to good antimicrobial and antioxidant activity.