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Updated: Jun 13, 2026

Methods for the Discovery of Novel Compounds Modulating a Gamma-Aminobutyric Acid Receptor Type A Neurotransmission
Published on: August 16, 2018
Synthesis and GABAA receptor activity of A-homo analogues of neuroactive steroids
María V Dansey1, Pablo H Di Chenna, Adriana S Veleiro
1Departamento de Química Orgánica and UMYMFOR (CONICET-FCEN), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, C1428EGA Buenos Aires, Argentina.
Abstract:
A procedure is described for the preparation of A-homo-5-pregnenes via an acid catalyzed rearrangement of cyclopropylcarbinols assisted by microwave irradiation. 3alpha-Hydroxy and 4alpha-hydroxy-A-homo-5-pregnen-20-one, analogues of the neuroactive steroid allopregnanolone, were obtained by means of a regioselective epoxidation of a double bond in the expanded A-ring, using a fructose-derived chiral ketone as catalyst and oxone as oxidant. Although both these compounds were marginally active in inhibiting TBPS binding to GABA(A) receptors, 3beta-hydroxy-A-homo-5-pregnen-20-one was almost as active as allopregnanolone. Reduction of the double bond of the latter compound resulted in a ten fold loss of activity.
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