furylfuramide furylfuramide furylfuramide (also known as af-2) is a synthetic nitrofuran derivative which was widely used as a food preservative in japan since at least 1965, but withdrawn from the market in 1974 when it was observed to be mutagenic to bacteria in vitro and thus suspected of carcinogenicity. this was confirmed later when animal testing found it to cause benign and malignant tumors in the mammary glands, stomachs, esophagi, and lungs of rodents of both sexes, although insufficient evidence exists in human exposure. furylfuramide names preferred iupac name (2z)-2-(furan-2-yl)-3-(5-nitrofuran-2-yl)prop-2-enamide other names (z)-2-(2-furyl)-3-(5-nitro-2-furyl)prop-2-enamideaf-2, tofuron,alpha-2-furyl-5-nitro-2-furanacrylamide, 2-(2-furyl)-3-(5-nitro-2-furyl)acrylic acid amide, a-(furyl)-b-(5-nitro-2-furyl)acrylic amide, trans-2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide, 2-(2-furyl)-3-(5-nitro-2-furyl) acrylamide, 2-furanacetamide, alpha-((5-nitro-2-furanyl)methylene)-, identifiers cas number 3688-53-7 y 3d model (jsmol) interactive image abbreviations af-2, ff chebi chebi:15660 y chembl chembl259747 y chemspider 4444292 y kegg d02528 y pubchem cid 5280707 unii 054nr2135y y comptox dashboard (epa) dtxsid9020033 inchi inchi=1s/c11h8n2o5/c12-11(14)8(9-2-1-5-17-9)6-7-3-4-10(18-7)13(15)16/h1-6h,(h2,12,14)/b8-6- ykey: lyahjfzldzdioh-vurmdhgxsa-n yinchi=1/c11h8n2o5/c12-11(14)8(9-2-1-5-17-9)6-7-3-4-10(18-7)13(15)16/h1-6h,(h2,12,14)/b8-6-key: lyahjfzldzdioh-vurmdhgxbb smiles o=()c2oc(/c=c(/c1occc1)c(=o)n)cc2 properties chemical formula c11h8n2o5 molar mass 248.19162 except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). y verify (what is yn ?) infobox references this successful use of bacterial mutagenicity as a screen for carcinogenicity confirmed the use of this methodology as a rapid and efficient test, in comparison to animal testing alone, and led to its further development. the availability of such simpler tests in turn gave rise to greater government oversight and testing of compounds to which the public would be exposed.