NMR-based platform for fragment-based lead discovery used in screening BRD4-targeted compounds

Area of Science:

• Biochemistry
• Medicinal Chemistry
• Structural Biology

Background:

• Fragment-based lead discovery (FBLD) is a key strategy in drug development.
• BRD4, a bromodomain-containing protein, is a target for various diseases.
• Developing novel inhibitors for BRD4 is of significant therapeutic interest.

Purpose of the Study:

• To establish an NMR-based FBLD platform for screening BRD4 inhibitors.
• To identify novel scaffolds targeting the human bromodomain of BRD4 (BRD4).
• To investigate the binding interactions of identified compounds with BRD4.

Main Methods:

• Utilized 1D NMR for fragment library generation and compound screening.
• Employed fluorescence anisotropy binding assays to assess inhibitory activity against BRD4(I).
• Applied 2D NMR and X-ray crystallography to elucidate binding modes.

Main Results:

• An NMR-based fragment library of 539 compounds was created.
• Eight novel hit compounds inhibiting BRD4(I) were identified.
• Four compounds (1, 2, 8, 9) showed IC50 values between 100-260 μmol/L, with compounds 1 and 2 binding in a non-acetylated lysine mimetic mode.

Conclusions:

• An effective NMR-based FBLD platform for discovering BRD4 inhibitors was successfully established.
• Four potential hit-to-lead candidates were identified for further optimization.
• Two identified compounds act as selective BRD4(I) inhibitors through a non-acetylated lysine mimetic mechanism.