Preparation of Dopaminergic N-Alkyl-benzyltetrahydro-isoquinolines Using a `One-Pot' Procedure in Acid Medium

Abstract

AbstractÐThe preparation of N-methyl-BTHIQ (4) from N-phenylethyl-phenacetamide (1) by cyclization, reduction and N-alkyl- ation in acid medium has been achieved in good yield in a `one-pot' procedure. Acylation of imine (2) intermediate a orded the Z and E stereoselectivity in the enamide formation. 6-Hydroxy-BTHIQ (7) shows selectivity for D2 dopamine receptors, while its N-methylated homologue (8) displays higher a nities for both D1 and D2 receptor types, with an unexpected increase in D1 dopamine receptor a nity.