Related Experiment Video
Updated: Aug 23, 2026

Lethality Bioassay Using Artemia salina L.
Published on: October 11, 2022
Cytotoxic epimeric withaphysalins from leaves of Acnistus arborescens
Maria Leopoldina Veras1, Maria Zeneide B Bezerra, Raimundo Braz-Filho
1Curso de Pós-Graduação em Química Orgânica, Departamento de Química Orgânica e Inorgânica, Centro de Ciências, Universidiade Federal do Ceará, Rua Cel Nunes de Melo 1127, 60430-270 Fortaleza, Ceará, Brazil.
Abstract:
Phytochemical analysis of the leaves of Acnistus arborescens (Solanaceae) resulted in the isolation of two new epimeric withaphysalins (17S,20R,22R)-5beta,6beta: 18,20-diepoxy-4beta,18-dihydroxy-1-oxowitha-24-enolide (2, 18R and 18S), together with the known withaphysalin F (1, 18R and 18S). Their structures were established by spectroscopic methods, including 2D NMR data and comparison with literature data. Compounds 1 and 2 dis-played potent cytotoxic activities against several cancer cell lines with IC50 values in the range of 0.20 to 1.46 microg/mL for 1 and 0.89 to 8.08 microg/mL for 2. The strong cytotoxicity presented by 1 suggests that in this series of compounds, the 2,3-unsaturated ketone moiety is an important pharmacophoric unit. The cytotoxic activity seemed to be related to DNA synthesis inhibition, as revealed by the reduction of 5-bromo-2'-deoxyuridine incorporation after 24 hours of incubation on leukemic cells.
Related Concept Videos
Physical Properties of Amines
Anthelminthic Agents
Antifungal Agents
Anticholinesterase Agents: Poisoning and Treatment
Irreversible agents form a strong bond with the cholinesterase enzyme, making it inactive. The breakdown of the phosphorylated enzyme is slower than the...