3,4-Dihydro-1,2-benzacridinic-5-carbonic acid 4-22-00-01422 (Beilstein Handbook Reference) 5,6-Dihydrobenz(c)acridine-7-carboxylic acid 83-93-2 BRN 0256492 Benz(c)acridine-7-carboxylic acid, 5,6-dihydro- Tetrofan Tetrophan