right<unk> s, or serotonin analogues, are organic compounds which may be thought of as being derived from<unk>  itself. The molecular structures of all<unk> s contain an indole ring, joined to an amino (NH2) group via an ethyl (−CH2–CH2−) sidechain. In<unk> s, the indole ring, sidechain, and/or amino group are modified by substituting another group for one of the hydrogen (H) atoms. Well-known<unk> s include serotonin, an important neurotransmitter, and melatonin, a hormone involved in regulating the sleep-wake cycle.<unk>  alkaloids are found in fungi, plants and animals; and sometimes used by humans for the neurological or psychotropic effects of the substance. Prominent examples of<unk>  alkaloids include psilocybin (from "Psilocybin mushrooms") and DMT. In South America, dimethyltryptamine is obtained from numerous plant sources, like chacruna, and it is often used in ayahuasca brews. Many synthetic<unk> s have also been made, including the migraine drug sumatriptan, and psychedelic drugs. The<unk>  structure, in particular its indole ring, may be part of the structure of some more complex compounds, for example: LSD, ibogaine, mitragynine and yohimbine. A thorough investigation of dozens of<unk>  compounds was published by Ann and Alexander Shulgin under the title TiHKAL.
Substituted tryptamine
Substituted phenethylamine
Substituted amphetamine
Loline alkaloid
Synthetic cannabinoids
Querulant
Nonbenzodiazepine
Organophosphate