A mild and eco-friendly method has been developed for the synthesis of a series of 1,3-diaminopropan-2-ols 8a-n. The epoxide of epichlorohydrin undergoes ring-opening with amines using MgSO4 or mixed metal oxides catalysts under mild and neutral conditions to afford the corresponding beta-amino alcohols in excellent yields. Preliminary evaluation of relaxant activity of 8b-n was carried out on rat tracheal rings contracted by carbachol 1 mu M. Most of the tested compounds exhibited significantly relaxant effects in a concentration-dependent manner. Compound 8n was found to be the most active, being twofolds more potent than theophylline (positive control). This compound has the potential for development as an anti-asthma drug.