A-ring modifications on the triazafluorenone core structure and their mGluR1 antagonist properties
T K Sasikumar1, Li Qiang, Duane A Burnett
1Merck Research Laboratories, Kenilworth, NJ 07033, USA. sasikumartk@yahoo.com
Bioorganic & Medicinal Chemistry Letters
|March 30, 2010
Summary
Modifications to the triazafluorenone core structure revealed that pyrimidine rings are well tolerated, with amino pyrimidine compounds demonstrating brain penetration and favorable pharmacokinetics.
Area of Science:
- Medicinal Chemistry
- Organic Synthesis
- Drug Discovery
Background:
- The triazafluorenone core is a scaffold of interest in medicinal chemistry.
- Understanding structure-activity relationships is crucial for developing new therapeutic agents.
Purpose of the Study:
- To investigate A-ring modifications on the triazafluorenone core.
- To evaluate the impact of different heterocyclic substitutions on chemical and pharmacological properties.
Main Methods:
- Synthesis of novel triazafluorenone analogs with A-ring modifications.
- Evaluation of chemical stability and synthetic versatility.
- Assessment of pharmacokinetic (PK) profiles, including brain penetration.
Main Results:
- Five-membered heterocycles (pyrazoles, isothiazoles) were not tolerated on the A-ring.
- The pyrimidine nucleus was well tolerated on the left-hand side of the core structure.
- Amino pyrimidine compounds (e.g., 24, 27) exhibited acceptable PK profiles and significant brain penetration.
- Compound 9 proved to be a versatile intermediate for further chemical transformations.
Conclusions:
- Pyrimidine-based modifications are promising for triazafluorenone derivatives.
- Compounds with favorable brain penetration and PK profiles were identified.
- The identified intermediate facilitates further exploration of this chemical space.
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