Butenafine-¹³C-d₃is intended for use as an internal standard for the quantification of butenafine by GC- or LC-MS. Butenafine is a benzylamine antifungal agent that has broad-spectrum activity against 87 strains of dermatophytes (MICs = 0.0015-0.05 µg/ml), 15 strains ofAspergillus(MICs = 0.025-0.78 µg/ml), 4 strains ofCryptococcus(MICs = 0.78-1.56 µg/ml), and 67 strains ofCandida(MICs = 3.13 to >100 µg/ml).¹It acts by inhibiting squalene epoxidase.²Butenafine (50 µM) inhibits the synthesis of ergosterol , a sterol in the cell membranes of fungi. Formulations containing butenafine have been used in the treatment of tinea pedis, tinea corporis, and tinea cruris.

1.Maeda, T., Takase, M., Ishibashi, A., et al.Synthesis and antifungal activity of butenafine hydrochloride (KP-363), a new benzylamine antifungal agentYakugaku Zasshi111(2)126-137(1991) 2.Hiratani, T., Asagi, Y., and Yamaguchi, H.Studies on antifungal mechanism of action of butenafine hydrochloride. II. Comparison in the response to drug treatment between a wild-type strain and tolciclate-resistant mutant strains of Sporothrix schenckiiNihon Ishinkin Gakkai Zasshi32(2)139-149(1991)