alkaloids displaying DNA intercalative antitumor activity.11 The
study of the relationships between the DNA binding properties
and the biological activity of carbazoles may lead to a better
understanding of the mechanisms involved. On the other hand,
drug interactions at the protein binding level significantly affect
the apparent distribution volume and their elimination rate.
The interactions of compounds with serum albumins have
received much attention via studying of antitumor pharmacokinetics
and structure−activity relationships. Therefore, it is
worthwhile to assess the interaction behavior of isolated
dimeric carbazole alkaloids with calf thymus DNA (CTDNA)
and bovine serum albumin (BSA) protein, to correlate
with their cytotoxic studies. With the rising cost of the plant
collections and preparation of crude extracts, it has become
necessary for natural product chemists to expand screening
targets.12 These facts prompted us to evaluate compounds 1−3
for antioxidant, anti-α-glucosidase, DNA binding, and cytotoxic
activities and interactions with bovine serum albumin (BSA).