Synthesis and characterization of Mannich bases of lawsone and their anticancer activity

Abstract

Natural and synthetic naphthoquinones are known for a large number of biological activities. Lawsone (2-hydroxy-1, 4-naphthoquinone) is a simplest naturally occurring compound obtained from dried henna (Lawsonia inermis) leaves. In literature, some lawsone derivatives have been reported to exhibit anticancer activity. Hence, a clean and facile one-pot protocol was developed for the synthesis of new aminonaphthoquinones derived from lawsone by three-component Mannich reaction, at room temperature for potential anti-cancer application. Herein we present a small library of Mannich bases with different amines and aromatic aldehydes with moderate to high yield. Synthesized compounds were characterized using various spectroscopic techniques. The anticancer activity (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay) along with nuclear morphology assessment (4′,6-diamidino-2-phenylindole or DAPI staining), apoptosis assessment (acridine orange/ ethidium bromide  staining), hemolysis and DNA ladder assay evaluated on human liver carcinoma cell line HepG2 are presented.

Graphical Abstract

Keywords:

• Lawsone
• Mannich bases
• anticancer activity
• aminonaphthoquinones
• HepG2 cells

Acknowledgments

The authors acknowledge DST-FIST for ¹H NMR facility and DST-PURSE, The Maharaja Sayajirao University of Baroda for Single Crystal X-Ray facility. The authors also acknowledge SAIF Chandigarh for ¹³C NMR analysis.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

PN received financial assistance from Gujarat State Biotechnology Mission (GSBTM), Gandhinagar. FS and HV received financial assistance from Sudeep pharma AACD Research fellowship and Lady Tata junior research fellowship, respectively.