3,4-Methylenedioxyamphetamine

3,4-Methylenedioxyamphetamine (MDA), also known as tenamfetamine (INN), is a psychedelic, stimulant, and empathogen-entactogen of the phenethylamine and amphetamine chemical classes. It is mainly used as a recreational drug, an entheogen, and a tool in use to supplement various types of practices for transcendence, including in meditation, psychonautics, and as an agent in psychedelic psychotherapy. It was first synthesized by G. Mannish and W. Jacobson in 1910. There are about 20 different synthetic routes described in the literature for its preparation.

Medical use
There are no currently accepted medical uses for MDA. However, researchers have investigated many possible uses in the past. It was first ingested in July 1930 by Gordon Alles who then licensed the drug to Smith Kline and French. MDA was first used in animal tests in 1939, and human trials began in 1941 in the exploration of possible therapies for Parkinson's disease. From 1949 to 1957, more than 500 human subjects were given MDA in an investigation of its potential use as an antidepressant and/or anorectic by Smith, Kline & French. The United States Army also experimented with the drug, code named EA-1298, while working to develop a truth drug or incapacitating agent. One human subject died in January 1953 after being intravenously injected with 450 mg of the drug. MDA was patented as a cough suppressant by H. D. Brown in 1958, as an ataractic by Smith, Kline & French in 1960, and as an anorectic under the trade name “Amphedoxamine” in 1961. Several researchers, including Claudio Naranjo and Richard Yensen, have explored MDA in the field of psychotherapy.

Synthesis
One method of MDA synthesis is to turn safrole into isosafrole via isomerization. The isosafrole is then oxidized, using a peroxyacid, to produce MDP2P (methylenedioxyphenylacetone). Finally, it is converted to MDA via reductive amination with ammonia. This synthesis is very similar to that of MDMA (Ecstasy) and of MDEA. Only disavantage is that this method, when used to produces MDA, gives extremely low yield. To achieve decent yield, MDP2P should first be reacted with hydroxylamine to produce Isosafrole Ketoxime (MDP2P Oxime). The oxime can then be reduced to MDOH, then MDA. Both reductions can be performed at the same time if the reactants are adjusted accordingly. The most common route is by starting from piperonal, and condensing it with nitroethane. The resulting nitro-isosafrole can then be reduced to MDA with a suitable reducing agent.

Recreational use
MDA began to appear on the recreational drug scene around 1963 to 1964. It was then inexpensive and readily available as a research chemical from several scientific supply houses. Although now illegal, MDA continues to be bought, sold, and used for recreational'love drug', due to its enhancement of sex. Unlike many amphetamine related drugs it did not reduce a man's ability to maintain an erection. It was often taken in conjunction with LSD to compliment its largely physical effects with the mental effects of the LSD.

Effects
A recreational dose of MDA is commonly between 100 and 160 mg. The “S” optical isomer of MDA is more potent than the “R” optical isomer as a psychostimulant, possessing greater affinity for the three monoamine transporter proteins (SERT, NET and DAT). Although there is some debate, the duration of the drug is now generally believed to be roughly 6 to 10 hours; but most individuals report the duration of the drug's effects to be around 5–6 hours, slightly longer than that of MDMA. (In the late 1990s, Alexander Shulgin changed his opinion of the duration to 3–6 hours).

MDA is thought to be similar in pharmacological mechanism of action and phenomenological effects to its more widely used N-methyl analogue MDMA (Ecstasy). Like MDMA, MDA causes serotonin and dopamine release by acting as a substrate at the SERT and DAT, respectively. This may explain the similar euphoric and empathogenic effects of the two compounds. However, (S)-MDA has a higher efficacy in stimulating the 5-HT2A receptor than (R)-MDMA; thus MDA tends to cause more psychedelic-like effects, such as visual hallucinations. MDMA can also produce psychedelic-like visual effects, though these are generally less pronounced than those of MDA, or require a heavier dose to become apparent.

MDA is said to share the empathogen/entactogenic effects of MDMA. While it is generally similar to MDMA, users report that MDA has more stimulant, or psychedelic hallucinogenic qualities and slightly less intense empathogen/entactogenic effects than MDMA. MDA is also considered less predictable than MDMA, with effects varying greatly from person to person. However, no properly controlled experiments have compared these drugs in humans. MDA was best known for its enhancement of the experiences of dancing and sex. Of particular note in the sexual aspect was its effect to greatly increase the enjoyment of receptive anal intercourse.

MDA also differs from its methylated cousin MDMA in its acute toxicity—it is clearly more toxic, with toxicity indicative of overstimulation of the central nervous system and the cardiovascular system. Symptoms of acute toxicity may include agitation, sweating, increased blood pressure and heart rate, dramatic increase in body temperature, convulsions, and death. Death is usually caused by cardiac effects and subsequent hemorrhaging in the brain (stroke). The website erowid.org lists the fatality rate at roughly 2 in 100,000 users, assuming it has similar rates as MDMA. The median lethal dose (LD50) in mice has been reported as 92 mg/kg by intraperitoneal injection.

Legality
In 1970, the Controlled Substances Act was enacted in the United States, placing MDA into Schedule I. It is similarly controlled in other nations. In Canada MDA is a Schedule III drug. Internationally, MDA is a Schedule I drug under the Convention on Psychotropic Substances. Many similar unscheduled MDXX chemicals can be prosecuted under the Federal Analog Act.