Chemistry and structure
The four possible stereoisomers of LSD. Only LSD is psychoactive.
LSD is an ergoline derivative. It is commonly synthesised by reacting diethylamine with an activated form of lysergic acid. Activating reagents include phosphoryl chloride[9] and peptide coupling reagents.[10] Lysergic acid is made by alkaline hydrolysis of lysergamides like ergotamine, a substance derived from the ergot fungus on rye, or from ergine (lysergic acid amide, LSA), a compound that is found in morning glory (Ipomoea tricolor) and hawaiian baby woodrose (Argyreia nervosa) seeds.
LSD is a chiral compound with two stereocenters at the carbon atoms C-5 and C-8, so that theoretically four different optical isomers of LSD could exist. LSD, also called (+)-D-LSD, has the absolute configuration (5R,8R). The C-5 isomers of lysergamides do not exist in nature and are not formed during the synthesis from D-lysergic acid. Retrosynthetically, the C-5 chiral center could be analysed as having the same chirality of the alpha carbon of the biological amino acid L-tryptophan, the precursor to all biosynthetic ergoline compounds.
However, LSD and iso-LSD, the two C-8 isomers, rapidly interconvert in the presence of base, as the alpha proton is especially acidic and can be deprotonated and reprotonated. Non-psychoactive iso-LSD which has formed during the synthesis can be separated by chromatography and can be isomerized to LSD.
A totally pure salt of LSD will emit small flashes of white light when shaken in the dark.[4] LSD is strongly fluorescent and will glow bluish-white under UV light.
[edit] Reactivity and degradation
"LSD," writes the chemist Alexander Shulgin, "is an unusually fragile molecule."[4] It is stable for indefinite time if stored as a solid salt or dissolved in water, at low temperature and protected from air and light exposure.
LSD has two sensitive chiral tertiary protons at the C5 and C8 positions that are prone to racemisation. The C8 proton is more labile due to the electron-withdrawing carboxamide attachment, but removal of the chiral proton at the C5 position (which actually was once also an alpha proton of the parent molecule tryptophan) is assisted by the inductively-withdrawing nitrogen and pi electron delocalisation with the indole ring.
LSD also has enamine-type reactivity because of the electron-donating effects of the indole ring. Because of this, chlorine destroys LSD molecules on contact; even though chlorinated tap water typically contains only a slight amount of chlorine, because a typical LSD solution only contains a small amount of LSD, dissolving LSD in tap water is likely to completely eliminate the substance.[4] The double bond between the 8-position and the aromatic ring, being conjugated with the indole ring, is susceptible to nucleophilic attacks by water or alcohol, especially in the presence of light. LSD often converts to "lumi-LSD", which is totally inactive in human beings (to the best of current knowledge).
A controlled study was undertaken to determine the stability of LSD in pooled urine samples.[11] The concentrations of LSD in urine samples were followed over time at various temperatures, in different types of storage containers, at various exposures to different wavelengths of light, and at varying pH values. These studies demonstrated no significant loss in LSD concentration at 25 °C for up to four weeks. After four weeks of incubation, a 30% loss in LSD concentration at 37 °C and up to a 40% at 45 °C were observed. Urine fortified with LSD and stored in amber glass or nontransparent polyethylene containers showed no change in concentration under any light conditions. Stability of LSD in transparent containers under light was dependent on the distance between the light source and the samples, the wavelength of light, exposure time, and the intensity of light. After prolonged exposure to heat in alkaline pH conditions, 10 to 15% of the parent LSD epimerized to iso-LSD. Under acidic conditions, less than 5% of the LSD was converted to iso-LSD. It was also demonstrated that trace amounts of metal ions in buffer or urine could catalyze the decomposition of LSD and that this process can be avoided by the addition of EDTA.
[edit] Dosage
White on White blotters (WoW)
Pink Elephant Blotters Containing 150μg of LSD
A single dose of LSD may be between 100 and 500 micrograms — an amount roughly equal to one-tenth the mass of a grain of sand. Threshold effects can be felt with as little as 25 micrograms of LSD.[6][6][12] Dosages of LSD are measured in micrograms (µg), or millionths of a gram. By comparison, dosages of most drugs, both recreational and medicinal, are measured in milligrams (mg), or thousandths of a gram. For example, an active dose of mescaline, roughly 0.2 to 0.5g, has effects comparable to 100 µg or less of LSD.[3]
Typical doses in the 1960s ranged from 200 to 1000 µg while street samples of the 1970s contained 30 to 300 µg. By the 1980s, the amount had reduced to between 100 to 125 µg, lowering more in the 1990s to the 20–80 µg range.[13]
Estimates for the lethal dosage (LD50) of LSD range from between 200 µg/kg to more than 1 mg/kg of human body mass, though most sources report that there are no known human cases of such an overdose. Other sources note one report of a suspected fatal overdose of LSD occurring in November 1975 in Kentucky in which there were indications that
*100 µg).[14][15] Experiments with LSD have also been done on animals; in 1962, an elephant named Tusko died shortly after being injected with 297 mg, but whether the LSD was the cause of his death is controversial (due, in part, to a plethora of other medicines administered simultaneously).[16]
[edit] History
Main article: History of LSD
LSD was first synthesized on November 16, 1938[17] by Swiss chemist Dr. Albert Hofmann at the Sandoz Laboratories in Basel, Switzerland as part of a large research program searching for medically useful ergot alkaloid derivatives. LSD's psychedelic properties were discovered 5 years later when Hofmann accidentally ingested an unknown quantity of the chemical.[18] The first intentional ingestion of LSD occurred at 4:20 PM on April 19, 1943[19], when Dr. Hofmann ingested 250 µg of LSD. He hypothesized this would be a threshold dose based on the dosages of other ergot alkaloids. Hofmann found the effects to be much stronger than he anticipated.[20] Sandoz Laboratories introduced LSD as a psychiatric drug in 1947.[21]
Beginning in the 1950s the US Central Intelligence Agency began a research program code named Project MKULTRA. Experiments included administering LSD to CIA employees, military personnel, doctors, other government agents, prostitutes, mentally ill patients, and members of the general public in order to study their reactions, usually without the subject's knowledge. The project was revealed in the US congressional Rockefeller Commission report in 1975.
In 1963 the Sandoz patents expired on LSD.[13] Also in 1963, the US Food and Drug Administration classified LSD as an Investigational New Drug, which meant new restrictions on medical and scientific use.[13] Several figures, including Aldous Huxley, Timothy Leary, and Al Hubbard, began to advocate the use of LSD. LSD became central to the counterculture of the 1960s. On October 24, 1968, possession of LSD was made illegal in the United States.[22] The last FDA approved human study with LSD, for use in dying cancer patients, ended in 1980. Legally approved and regulated psychiatric use of LSD continued in Switzerland until 1993.[23] Today, medical research is resuming around the world.[24]
[edit] Effects
[edit] Physical
LSD reliably causes pupil dilation, reduced appetite, and wakefulness. Other physical reactions to LSD are highly variable and nonspecific, and some of these reactions may be secondary to the psychological effects of LSD. The following symptoms have been reported: numbness, weakness, nausea, hypothermia or hyperthermia (decreased or increased body temperature), elevated blood sugar, goose bumps, increase in heart rate, jaw clenching, perspiration, saliva production, mucus production, sleeplessness, hyperreflexia, and tremors. Uterine contractions have been reported in animals.[citation needed] Some users, including Albert Hofmann, report a strong metallic taste for the duration of the effects.[25]
LSD is not considered addictive by the medical community.[26] Rapid tolerance build-up prevents regular use, and there is cross-tolerance shown between LSD, mescaline[27] and psilocybin.[28] This tolerance diminishes after a few days without use and is probably caused by downregulation of 5-HT2A receptors in the brain.[citation needed]
[edit] Psychological