Synthesis of β-carboline fatty alcohol hybrid molecules and characterization of their biological and antioxidant activities

Nine new beta-carboline fatty alcohol hybrids were synthesized from natural amino acid L-tryptophan by the conjugation of 10-undecen-1-ol via ester linkage. All the synthesized products were characterized in each step by spectral techniques (H-1, C-13 NMR mass and HRMS). Synthesized B-carboline derivatives (7a-i) were screened for biological activities such as antimicrobial, antifungal, anti-biofilm and anticancer. Compounds 7d and 7f showed most potent antimicrobial activity against Bacillus subtilis MTCC 121, Micrococcus luteus MTCC 2470, Staphylococcus aureus MTCC 96 and Candida albicans MTCC 3017 microbial strains ranged from 2.8 to 28.3 mu g/mL. Biofilm inhibition assay showed that the compound 7f exhibited better activity against three bacterial stains with IC50 values from 1.8 to 2.9 mu M. All the B-carboline derivatives showed cytotoxic activity, among them compounds 7f and 7h (IC50 values 9.1 and 11.4 mu M) were exhibited potential activity. Free radical scavenging activity via DPPH assay revealed that compound 7g acted as a good antioxidant molecule than all the tested compounds. (C) 2021 Published by Elsevier B.V. on behalf of King Saud University.

Automated summary

The nine new beta-carboline fatty alcohol hybrids synthesized from L-tryptophan showed potent antimicrobial, antifungal, antibiofilm, and anticancer activities. Compounds 7d and 7f exhibited the most potent antimicrobial activity, while compound 7g showed the best antioxidant activity among all tested compounds.