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Since our study showed that sulfone derivatives' action mode creates a lesser risk of inducing widespread resistance among Candida spp., we continued verifying sulfones' antifungal activity using the following newly synthesized derivatives: bromodichloromethy-4-hydrazinyl-3-nitrophenyl sulfone (S1), difluoroiodomethyl-4-hydrazinyl-3-nitrophenyl sulfone (S2), and chlorodifluoromethyl-4-hydrazinyl-3-nitrophenyl sulfone (S3). As the mechanism by which sulfones gain access to the cytoplasm has not been elucidated yet, in order to track S1-3 , we coupled their hydrazine group with BODIPY (final S1-3 BODIPY -labelled were named SB1-3). This approach allowed us to follow the vital internalization and endocytic routing of SB1-3 , while BODIPY interacts primarily with fungal surfaces, thus confirming that S1-3 and their counterparts SB1-2 behaved as non-typical agents by damaging the cell membrane and wall after being endocytosed (SB1-3 fluorescence visible inside the unlysed sessile cells). Thus greatly decreasing the likelihood of the appearance of strains resistance. Core sulfones S1-3 are a promising alternative not only to treat planktonic C. albicans but also biofilm-embedded cells. In the flow cytometric analysis, the planktonic cell surface was digested by S1-3, which made the externalized PS accessible to AnnexinV binding and PI input (accidental cell death ACD). The occurrence of ACD as well as apoptosis (crescent-shaped nuclei) and anoikis of sessile cells (regulated cell death by 100%-reduction in attachment to epithelium) was assessed through monitoring the AO/PI/HO342 markers. CLSM revealed the invasion of S1-3 and SB1-3 in C. albicans without inducing cell lysis. This was a novel approach in which QCM-D was used for real-time in situ detection of viscoelastic changes in the C. albicans biofilm, and its interaction with S1 as a representative of the sulfones tested. S1 (not toxic in vivo) is a potent fungicidal agent against C. albicans and could be administered to treat invasive candidiasis as a monotherapy or in combination with antifungal agents of reference to treat C. albicans infections. Image 1 • Sulfones are active against planktonic and biofilm-embedded C. albicans cells. • BODIPY-labelled Sulfones display endocytic routing in C. albicans. • Sulfones lead to accidental cell death, apoptosis, and anoikis in C. albicans. • Real time treatment with Sulfone influences the biofilm remodelling in the QCM-D study. [ABSTRACT FROM AUTHOR]