Comparison of Small Molecule Biotransformation Half-Lives between Activated Sludge and Soil: Opportunities for Read-Across?

Compartment-specific degradation half-lives are essential pieces of information in the regulatory risk assessment of synthetic chemicals. However, their measurement according to regulatory testing guidelines is laborious and costly. Despite the obvious ecological and economic benefits of knowing environmental degradability as early as possible, its consideration in the early phases of rational chemical design is therefore challenging.

Synthesis and stability of boratriazaroles.

We describe the synthesis and stability analysis of novel boratriazaroles that can be viewed as bioisosteres of imidazoles or pyrazoles. These heterocycles could conveniently be obtained by condensing a boronic acid and amidrazone 1 in various solvents. A detailed stability analysis of selected compounds at different pH values as a function of time led to the identification of steric hindrance around the boron atom as a key element for stabilization.