Background: A set of novel sulfanyl aminonaphthoquinone derivatives (5a-j) were
synthesized starting from 2,3-dichloro-1,4-naphthoquinone (1). The amine substituents were
introduced via a nucleophilic substitution at reflux temperature. Subsequent reactions of 2-chloro-
3-arylamino-1,4-naphthoquinones (3a-d) with different thiols (4a-c) led to the formation of the
desired amino- and thio- substituted products (5a-j).
Methods: The purity and identity of the synthesized compounds were verified with IR, 1H and 13C
NMR, and MS spectroscopy. In vitro antimicrobial activity was evaluated in a panel of seven
bacterial strains (three Gram-positive and four Gram-negative bacteria) and one fungi with an
additional study of antibiofilm activities. The anticancer activities of two selected compounds
(5e and 5f) were evaluated against 60 human tumor cell lines derived from nine neoplastic diseases
by National Cancer Institute (NCI).
Results: As a result, compound (5e) was identified as a hit with antibacterial efficiency against
human originated pathogens S. aureus with minimal inhibitory concentration (MIC) of 19.53 μg/mL.
When considering the antibiofilm activities of antibacterial molecule 5e against the S. aureus biofilms,
the minimum biofilm eradication concentration (MBEC) value was 10000 μg/mL. Concerning
on anticancer activities, both compounds (5e and 5f) exhibited moderate anticancer activities on
some of tumor cells, but no activity against normal peripheral blood mononuclear cells (PBMC). In
addition, docking study was used to provide further insights into the experimental observations.
Conclusion: Taken together, compound 5e could be considered as a promising starting point for