The structural simplification of lysergic acid as a natural lead for synthesizing novel anti-Alzheimer agents

Bioorg Med Chem Lett. 2021 Sep 1:47:128205. doi: 10.1016/j.bmcl.2021.128205. Epub 2021 Jun 15.


Alzheimer's disease (AD) is a neurodegenerative disorder, projected to be the second leading cause of mortality by 2040. AD is characterized by a progressive impairment of memory leading to dementia and loss of ability to carry out daily functions. In addition to the deficiency of acetylcholine release in synapse, there are other mechanisms explaining the etiology of the disease. The most disputing ones are associated with the accumulation of damaged proteins β-amyloid (Aβ) and hyperphosphorylated tau outside and inside neurons, respectively. Lysergic acid derivatives have been shown to possess promising anti-Alzheimer effect. Moreover, lysergic acid structure encompasses the general structural requirements for acetylcholinesterase inhibition. In this study, sixteen analogues, derived from lysergic acid structure, were synthesized. Heck and Mannich reactions were carried out to 4-bromo indole nucleus to generate potentially active analogues. Some of them were subsequently cyclized by nitromethane and zinc reduction procedures. Some of these compounds showed neuroprotective and anti-inflammatory effects stronger than the currently used anti-Alzheimer drug; donepezil. Some of the synthesized com-pounds showed a noticeable acetylcholinesterase inhibition. Twelve molecular targets attributed with AD etiology were tested versus the synthesized compounds by in silico modeling. Docking scores of modeling were plotted against in vitro activity of the compounds. The one afforded the strongest positive correlation was ULK-1 which has a significant role in autophagy.

Keywords: Alzheimer; Lysergic acid; Neuroprotection; Structural simplification.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcholinesterase / metabolism*
  • Alzheimer Disease / drug therapy*
  • Alzheimer Disease / metabolism
  • Animals
  • Biological Products / chemical synthesis
  • Biological Products / chemistry
  • Biological Products / pharmacology*
  • Cell Survival / drug effects
  • Cholinesterase Inhibitors / chemistry
  • Cholinesterase Inhibitors / pharmacology*
  • Dose-Response Relationship, Drug
  • Lysergic Acid / chemical synthesis
  • Lysergic Acid / chemistry
  • Lysergic Acid / pharmacology*
  • Molecular Structure
  • Neuroprotective Agents / chemical synthesis
  • Neuroprotective Agents / chemistry
  • Neuroprotective Agents / pharmacology*
  • PC12 Cells
  • Rats
  • Structure-Activity Relationship


  • Biological Products
  • Cholinesterase Inhibitors
  • Neuroprotective Agents
  • Acetylcholinesterase
  • Lysergic Acid