High Quality Content by WIKIPEDIA articles! Methoxyflurane (International Nonproprietary Name, formerly marketed as Penthrane by Abbott Laboratories) is a halogenated ether that was in clinical use as an volatile inhalational anesthetic from its introduction by Joseph F. Artusio et al in 1960 until around 1974. It was first synthesized in the late 1940s by William T. Miller and his team of chemists following their involvement in the Manhattan Project. Methoxyflurane is classified as a halogenated hydrocarbon under the ATC code N01 (anesthetics) subgroup of the Anatomical Therapeutic Chemical Classification System, but its chemical structure indicates that it is better described as a halogenated ether.