10,13,18,19-Tetraoxa-3-thiatricyclo(13.2.1.1(sup 5,8))nonadeca-5,7,15,17-tetraene-9,14-dione 2-Furoic acid, 5,5'-thiodimethylenedi-, cyclic ester with ethylene glycol 73853-09-5 BRN 1658680