One Response to “Phenylethylamines”

1. admin says:

   August 31, 2009 at 11:03 pm

   In article <2…@laidbak.UUCP> r…@laidbak.UUCP (Ray Dueland) writes:
   >What are the basis for the pharmacological differences between
   >phenylpropanolamines and phenylpropylamines (amphetamines)?  The 1-hydroxyl
   >is the only difference. but I wondered if the difference wasn’t do to less
   >preferential transport across the blood brain barier caused by the polar
   >1-hydroxyl

   That is the conventional wisdom.  Conformation may also have some effect:
   nor-pseudoephedrine, an isomer of phenylpropanolamine, is said to have a
   greater central stimulant effect.

   >Have phenylpropanolamines ever been acetylated or oxidated to the ketone?
   >What were the results?

   Cathinone is the ketone analog of phenylpropanolamine (I’m not sure of its
   chirality), one of the alkaloids found in the kat plant.  It is apparently
   (and not surprisingly) a stimulant.  Diethylpropion is an anorectic drug
   sold under the names Tenuate and Tepanil.  It is a substituted phenyl-
   propanone like cathinone, but with a diethylamino group.  If you substitute
   the hydrogens of phenylpropanolamine at the hydroxy group and at the amino
   group with an ethylene bridge (CH2-CH2), you get the cyclic substituted
   morpholine, phenmetrazine (Preludin), an anorectic drug which is
   pharmacologically indistinguishable from the amphetamines.

   –
   Steve Dyer
   d…@ursa-major.spdcc.com aka {ima,harvard,rayssd,linus,m2c}!spdcc!dyer
   d…@arktouros.mit.edu