Tolnaftate (NP-27) is a synthetic thiocarbamate used as an anti-fungal agent. . IC50 & Target: Antifungal^[1]. In Vitro: Tolnaftate (NP-27) blocked sterol biosynthesis in fungal cells and cell extracts, with accumulation of squalene. This point of action was confirmed by the direct inhibition of microsomal squalene epoxidase from Candida albicans^[1]. Tolnaftate (NP-27) inhibited sterol biosynthesis, At 100 microM, tolnaftate caused up to a 30% release of intracellular [14C]aminoisobutyric acid^[2].