Isosteric replacement of the indole nucleus by benzothiophene and benzofuran in a series of indolylglyoxylylamine derivatives with partial agonist activity at the benzodiazepine receptor.

A number of benzothienyl- and benzofurylglyoxylylamine derivatives, which are analogues of previously described mdolylglyoxylylammes with a pamal agonist activity, are reported in this paper They were synthesized and tested to verify the importance of the presence of the indole NH group m the interaction of this class of compounds with the benzodlazepine agonist receptor site, since it was reported m literature that a hydrogen bond donor group such as NH was not necessary to ehclt an agonlst response, Several thienylglyoxylylamme derivatives were also prepared and tested. None of the compounds showed a high affinity at the BzR, demonstrating that the mdole NH plays a decisive role in the interaction of the agomst glyoxylylamine ligands with the receptor site.