Natural Killer T (NKT) cells recognise lipid antigens presented by the MHC Class I-like molecule CD1d. Following activation, they rapidly secrete a broad range of immunoregulatory cytokines that can influence other mediators of immune responses and thus represent a promising therapeutic target for cancer and other diseases. The most extensively studied are type 1 NKT cells, which recognise a derivative of a marine sponge glycolipid α-galactosylceramide (α-GalCer), express a semi-invariant T cell receptor (TCR), and have a well-established role in the immune system. Much less is known about type 2 NKT cells, which do not recognise α-GalCer and express a diverse TCR repertoire. An early study showed that a non-lipid molecule –phenyl 2,2,4,6,7-pentamethyldihydrobenzofuran-5-sulfonate (PPBF)– can also be detected by type 2 NKT cells in the context of CD1d. The structure of PPBF shares similarities with several sulfonamide drugs that have been reported to cause hypersensitivity in humans suggesting that type 2 NKT cells may be involved in such hypersensitivity reactions. Through investigation of various PPBF analogues, we identify 3-chlorophenyl 2,2,4,6,7-pentamethyldihydrobenzofuran-5-sulfonate (ClPPBF) as a stronger activator of type 2 NKT cells than the original PPBF compound. Importantly, we demonstrate that type 2 NKT cell modulation by PPBF is due to TCR recognition of PPBF-CD1d complexes. Using CD1d-ClPPBF tetramers we identified a novel population of type 2 NKT cells that specifically recognises these non-lipid antigens. Single-cell-sequencing of these cells revealed a polyclonal TCR repertoire distinct from type 1 NKT cells. Through the generation of retrovirally TCR-transduced cell lines we were able to validate the antigen-specificity of sorted cells. This study provides valuable insight into the diversity of antigens recognized by CD1d-restricted NKT cells, suggesting that small non-lipid molecules can modulate CD1d-mediated NKT cell activation. We are now addressing whether NKT cells play a role in hypersensitivity driven by PPBF-‘like’ drugs.