Clotrimazole-d₅is intended for use as an internal standard for the quantification of clotrimazole by GC- or LC-MS. Clotrimazole is an imidazole antifungal agent.¹It is active against a variety of fungi, includingC. albicans,A. fumigatus,S. cerevisiae,C. neoformans,T. mentagrophytes, andM. canis(MICs =<0.05-3.13 µg/ml).²It inhibits the voltage-gated potassium channel K_v1.3 and the intermediate conductance calcium-activated potassium channel (IKCa₁/KCa_3.1; IC₅₀s = 6 and 0.07 µM, respectively) and decreases proliferation of HaCaT keratinocytes (EC₅₀= 15 µM).³Topical application of clotrimazole (1%) reduces oxazolone-induced ear swelling in an oxazolone-sensitized mouse model of delayed-type hypersensitivity. Clotrimazole (10 µM) also inhibits proliferation of A549 lung, HT-29 colon, and MM-RU melanoma cancer cells.⁴Formulations containing clotrimazole have been used in the treatment of fungal skin infections.

1.Burgess, M.A., and Bodey, G.P.Clotrimazole (Bay b 5097): In vitro and clinical pharmacological studiesAntimicrob. Agents Chemother.2(6)423-426(1972) 2.Shadomy, S.In vitro antifungal activity of clotrimazole (Bay b 5097)Infect. Immun.4(2)143-148(1971) 3.Pegoraro, S., Lang, M., Dreker, T., et al.Inhibitors of potassium channels Kv1.3 and IK-1 as immunosuppressantsBioorg. Med. Chem. Lett.19(8)2299-2304(2009) 4.Benzaquen, L.R., Brugnara, C., Byers, H.R., et al.Clotrimazole inhibits cell proliferation in vitro and in vivoNat. Med.1(6)534-540(1995)