Salicylic acid 4-aminosalicylic acid, sandulpiride, and landetimide (via Salethamide). Salicylic acid was one of the original starting materials for making acetylsalicylic acid (aspirin) in 1897. Bismuth subsalicylate, a salt of bismuth and salicylic acid, is the active ingredient in stomach relief aids such as Pepto-Bismol, is the main ingredient of Kaopectate and "displays anti-inflammatory action (due to salicylic acid) and also acts as an antacid and mild antibiotic". Other derivatives include methyl salicylate used as a liniment to soothe joint and muscle pain and choline salicylate used topically to relieve the pain of mouth ulcers. Salicylic acid has the formula CH(OH)COOH, where
Gallic acid cyclic ether-esters (depsidones). Gallic acid is commonly used in the pharmaceutical industry as a standard for determining the phenol content of various analytes by the Folin-Ciocalteau assay; results are reported in gallic acid equivalents. Gallic acid can also be used as a starting material in the synthesis of the psychedelic alkaloid mescaline. The name is derived from oak galls, which were historically used to prepare tannic acid. Despite the name, gallic acid does not contain gallium. Salts and esters of gallic acid are termed "gallates". Gallic acid is an important component of iron gall ink, the standard European writing and