New chemical structures were synthetized with fungicidal activity. These molecules (labeled A5a-d) have two symmetrical 12-carbon tails derived from N,N-dimethyldodecylamine and as a spacer they have an N-alkylamine group (dodecanol (A5a), farnesol (A5b), menthol (A5c) and galactose diacetonide (A5d) as alkyl group), in addition the spacer has a beta hydroxy group derived from epichlorohydrin. The β-hydroxy amino/ammonium group causes disruption of the plasma membrane and inhibition of essential enzymes necessary for the development of microorganisms, also the functional groups derived from simple and complex alcohols give it antifungal capacity. The antifungal activity was measured by MIC (minimum inhibitory concentration) through broth dilution technique using Candida albicans ATCC 64548, Candida papapsilopsis ATCC 22019, Aspergillus niger ATCC 16404 and a wild strain of Alternaria alterna (regional isolate) was also tested as a reference. The procedures were adjusted to the reference methods approved by the CLSI (Clinical and Laboratory Standards Institute), or formerly called NCCLS (National Committee for Clinical Laboratory Standards) (M27-A2, NCCLS, 2008). The most active structure was in these tests selected to carry out the environmental impact studies like Ecotoxicity tests with Daphnia magna and Chlorella vulgaris. The effectiveness as a wood preservative comparing with 2-(thiocyanomethylthio)benzothiazole and creosote (commercial reference compounds) was also probed. The namely compound A5d have highest antifungal activity, lower toxicity compared with commercial products and results wood preservative effective. The most sensitive strain was A. alternate and A. niger the most resistant.