title: Synthesis and structure-activity relationships of 5H,11 H-[I]benzopyrano[4,3-g]benzopyran-9-carboxylic acids.
abstract: The synthesis and properties of the title compounds 1 are described. Many of these compounds are potent inhibitors of the passive cutaneous anaphylaxis reaction of rats against egg albumin challenge. Structural variations include substitutions in the 2, 3, 4, 5, 7, and 12 position of the nucleus 1. A novel rearrangement from a compound of the related [3,4-f] series to this group is reported.
mesh_terms: D000818:Animals; D001578:Benzopyrans / Q000138:chemical synthesis* / Q000494:pharmacology; D006967:Hypersensitivity / Q000188:drug therapy*; D051381:Rats; D013329:Structure-Activity Relationship
chemical_list: D001578:Benzopyrans