The reaction of the title acid (H2fspa) with lead(II) acetate and dimethyl‐ or diphenyllead(IV) acetate in alcoholic medium gives the 1:1 complexes [Pb(fspa)] and [PbR2(fspa)] (R = Me, Ph). When the reaction was carried out in the presence of diisopropylamine (Q), the [HQ]2[Pb(fspa)2] and [HQ]2[PbPh2(fspa)2] derivatives formed in low yield. Additionally, the compounds Na[PbMe2(OAc)3], [PbPh2(fspa)(DMSO)] and [PbPh2(fspa)(DMSO)]·DMSO were also isolated as crystalline solids in subsequent crystallization processes. All these compounds were characterized by IR and NMR (1H and 13C) spectroscopy and, in some cases, by X‐ray diffractometry and 207Pb NMR spectroscopy. Pig renal proximal tubule LLC‐PK1 culture cells were used to determine in vitro the nephroprotective effect of H2fspa, [HQ]2[Zn(fspa)2], vitamin B1 and vitamin B6 against PbMe2(NO3)2 toxicity. The beneficial effects of the acid, the zinc(II) complex and/or their combinations with vitamin B1 (thiamine nitrate) are described.