SYNTHESIS: To a stirred solution of 0.4 g 2,5-dimethoxy-4-iodoamphetamine hydrochloride (
DOSAGE: greater than 2.6 mg.
EXTENSIONS AND COMMENTARY: This base, if it were given a code name based upon its substituents arranged in their proper alphabetical order, would have to be called something like DNDIA, which is quite unpronounceable. But by a rearrangement of these terms, one can achieve IDNNA (Iodo-Dimethoxy-N,N-dimethyl-Amphetamine) which has a nice lilt to it.
One of the major goals of research in nuclear medicine is a drug that can be used to demonstrate the brain blood flow pattern. To do this job, a drug should demonstrate four properties. First, it must carry a radioactive isotope that is a positron emitter (best, a fluorine or an iodine atom, for use with the positron camera) that can be put onto the molecule quickly, synthetically, and which will stay on the molecule, metabolically. Second, as to brain entry, the drug should be rapidly and extensively taken up by brain tissue, without being selectively absorbed or concentrated at any specific sites. In other words, it should go where the blood goes. Thirdly, the absorption should be strong enough that it will stay in the brain, and not be washed out quickly. This allows time to both locate and count the radioactivity that was carried in there. And lastly, the drug must be without pharmacological action.
IDNNA looked like a promising candidate when tried with a radioactive iodine label, and there was quite a flurry of interest in using it both as an experimental drug, and as a prototype material for the synthesis of structural variants. It went in quickly, extensively and quite diffusely, and it stayed in for a long time.
But was it pharmacologically active? Here one finds a tricky road to walk. The animal toxicity and behavioral properties can be determined in a straightforward manner. Inject increasing amounts into an experimental animal and observe him closely. IDNNA was quite inert. But, it is a very close analogue to the extremely potent psychedelic
It was assayed up to levels where 122I that would be used, would dictate that only an extremely small amount of the drug would be required. One would be dealing, not with milligram quantities, but with microgram quantities, or less.
Some fifteen close analogues of IDNNA were prepared, to see if any had a better balance of biological properties. A valuable intermediate was an iodinated ketone that could be used either to synthesize IDNNA itself or, if it were to be made radio-labelled, it would allow the preparation of any desired radioactive analogue in a single synthetic step. The iodination of p-dimethoxybenzene with iodine monochloride in acetic acid gave 2,5-diiodo-1,4-dimethoxybenzene as white crystals from acetonitrile, with a mp of 167–168 °C. Anal. (C8H8I2O2) C,H. Treatment of this with an equivalent of butyllithium in ether, followed with N-methyl formanilide, gave 2,5-dimethoxy-4-iodobenzaldehyde as pale yellow crystals from ethanol, with a mp of 136–137 °C. Anal. (C9H9IO3) C,H. This, in solution in nitroethane with a small amount of anhydrous ammonium acetate, gave the nitrostyrene 1-(2,5-dimethoxy-4-iodophenyl)-2-nitropropene as gold-colored crystals from methanol, mp 119–120 °C. Anal. (C11H12INO4) C,H. This was smoothly reduced with elemental iron in acetic acid to give 2,5-dimethoxy-4-iodophenylacetone as white crystals from methylcyclopentane. These melted at 62–63 °C and were both spectroscopically and analytically correct. Anal. (C11H13IO3) C,H.
This intermediate, when reductively aminated with dimethylamine, gives IDNNA identical in all respects to the product from the dimethylation of 131I NaI in acetic acid at 140 °C for 10 min, giving the radioactive compound by exchange, and this was reductively aminated with over a dozen amines to give radioactive products for animal assay. There was produced in this way, 2,5-dimethoxy-4-iodo-N-alkyl-amphetamine where the alkyl group was
3-(dimethylaminopropyl) . Several dialkyl homologue were made, with the alkyl groups being dimethyl (IDNNA itself),
The diethyl compound without the iodine is 2,5-dimethoxy-N,N-diethylamphetamine, which was prepared by the reductive alkylation of
None of these many iodinated IDNNA analogues showed themselves to be superior to IDNNA itself, in the rat model, and none of them have been tasted for their psychedelic potential in man.
13 May 2016 · · Isomer Design
About PiHKAL · info
This version of Book II of PiHKAL is based on the Erowid online version, originally transcribed by Simson Garfinkle and converted into HTML by Lamont Granquist. I drew also on “Tyrone Slothrop’s” (Unfinished) Review of PIHKAL to enumerate the many analogues mentioned in PiHKAL but not described at length. Many, many others have since been added.
I have tried here to expunge any artifacts introduced by the earlier transcriptions and restore the typographic niceties found in the printed edition. I’ve also made minor changes to some chemical names in line with current nomenclature practice. Typically the change is little more than expanding a prefix or setting it in italics. The history page has further details.
“At the present time, restrictive laws are in force in the United States and it is very difficult for researchers to abide by the regulations which govern efforts to obtain legal approval to do work with these compounds in human beings.“No one who is lacking legal authorization should attempt the synthesis of any of the compounds described in these files, with the intent to give them to man. To do so is to risk legal action which might lead to the tragic ruination of a life. It should also be noted that any person anywhere who experiments on himself, or on another human being, with any of the drugs described herein, without being familiar with that drug’s action and aware of the physical and/or mental disturbance or harm it might cause, is acting irresponsibly and immorally, whether or not he is doing so within the bounds of the law.”
The copyright for Book I of PiHKAL has been reserved in all forms and it may not be distributed. Book II of PiHKAL may be distributed for non-commercial reproduction provided that the introductory information, copyright notice, cautionary notice and ordering information remain attached.
PiHKAL is the extraordinary record of the authors’ years exploring the chemistry and transformational power of phenethylamines. This book belongs in the library of anyone seeking a rational, enlightened and candid perspective on psychedelic drugs.
Though Sasha and Ann have put Book II of PiHKAL in the public domain, available to anyone, I strongly encourage you to buy a copy. We owe them — and there’s still nothing quite like holding a real book in your hands.
PiHKAL (ISBN 0-9630096-0-5) is available for US$24.50 (plus $10 domestic first-class shipping) from Transform Press.Transform Press,
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