Dziaduszek, Jerzy published the artcileAnorectal drug products for over-the-counter human use; final monograph, Synthetic Route of 637-58-1, the publication is Federal Register (1990), 55(150), 31776-83, database is CAplus.
Active ingredients and permitted combinations of active ingredients in over-the-counter anorectal products for external or intrarectal administration are given under the Federal Food, Drug, and Cosmetic Act. Classes of active ingredients include anesthetics, vasoconstrictors, protectants, analgesics, antipruritics, astringents, and keratolytics. Labeling of anorectal drug products is also considered.
Federal Register published new progress about 637-58-1. 637-58-1 belongs to ethers-buliding-blocks, auxiliary class Inhibitor, name is 4-(3-(4-Butoxyphenoxy)propyl)morpholine hydrochloride, and the molecular formula is C13H8BrIN2O2S, Synthetic Route of 637-58-1.
Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem