(3S,4R)-3-ethyl-4-[(3-methylimidazol-4-yl)methyl]oxolan-2-one;nitric acid; (3S,4R)-3-ethyl-4-[(1-methyl-1H-imidazol-5-yl)methyl]oxolan-2-one;nitric acid; (3S,4R)-3-ethyl-4-((1-methyl-1H-imidazol-5-yl)methyl)dihydrofuran-2(3H)-one nitrate; 2(3H )-Furanone, 3-ethyldihydro-4-[(1-methyl-1H -imidazol-5-yl)methyl]-, (3S-cis)-, mononitrate (USP)