Quantitative Structure‐Fluorescence Property Relationship Analysis of a Large BODIPY Library

A quantitative structure‐fluorescence property relationship (QSPR) analysis of a large 288‐membered library based on a single fluorescent BODIPY scaffold is presented for the first time. BODIPY is a versatile fluorescent scaffold with outstanding photophysical properties. Absorption ( λ abs ) and fluorescence emission ( λ em ) wavelength maxima were modeled with help of stepwise multiple linear regression (MLR) and support vector regression (SVR). The models were rigorously validated by 10‐times 10‐fold cross‐validation (CV), y ‐scrambling CV and with an external validation set. Non‐linear SVR models ( R 2 =0.92 and Q 2 =0.71 for λ abs ; R 2 =0.89 and Q 2 =0.69 for λ em ) performed significantly better than linear models. A small root mean squared error ( RMSE ) of 5.62 nm and 11.07 nm was achieved for λ abs and λ em , respectively, and confirmed by external validation. A novel intramolecular charge transfer descriptor was developed based on the QSPR analysis and its inclusion in the modeling significantly improved models of λ em . We conclude that QSPR is a useful tool for modeling λ abs and λ em of BODIPY fluorophores and suggest QSPR as an ideal partner for the design of compounds with tailored fluorescence properties in a diversity‐oriented fluorescence library approach (DOFLA).