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Updated: Jun 8, 2026

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
Published on: August 18, 2014
Synthesis and α1-adrenoceptor antagonist activity of tamsulosin analogues
Gianni Sagratini1, Piero Angeli, Michela Buccioni
1Scuola in Scienze del Farmaco e dei Prodotti della Salute, Università di Camerino, Via S. Agostino 1, 62032 Camerino, Italy.
Abstract:
Tamsulosin (-)-1 is the most utilized α(1)-adrenoceptor antagonist in the benign prostatic hyperplasia therapy owing to its uroselective antagonism and capability in relieving both obstructive and irritative lower urinary tract symptoms. Here we report the synthesis and pharmacological study of the homochiral (-)-1 analogues (-)-2-(-)-5, bearing definite modifications in the 2-substituted phenoxyethylamino group in order to evaluate their influence on the affinity profile for α(1)-adrenoceptor subtypes. The benzyl analogue (-)-3, displaying a preferential antagonist profile for α1A-than α1D-and α1B-adrenoceptors, and a 12-fold higher potency at α1A-adrenoceptors with respect to the α1B subtype, may have improved uroselectivity compared to (-)-1.
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