2 resultados para 1345

em Brock University, Canada


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The monoconjugates of phenolic acids (i.e. coumaric acid) with polyamines such as spermidine and spermine are strikingly similar to some toxins from spiders and predatory wasps. Many plants contain phenolic acid polyamine conjugates and there is some reliable information supporting their roles as plant defense chemicals. Eleven monoacylated compounds of diamines, triamines, tetraamines and oxa-polyamine amines were prepared in three to seven steps: 22, 23, 24, 25, 26, 27, 28, 29, 30, 31 and 32. The synthesis proceeds through stepwise construction of the polyamine backbone (as in 62 and 72), followed by protection and deprotection steps of the amino functions. Desymmetrization of readily available and prepared symmetrical polyamines is a key step in the synthesis. The protecting groups employed were tert-butoxycarbonyl (BOC) and trifluoroacetyl (TFA) group which were removed under different conditions: acid and base respectively. Deprotection and refunctionalization of the polyamine reagent demonstrated the versatility of these systems for N-acylation.

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The Seagram Museum was opened on May 16th, 1984 by the Honourable William G. Davis, Premier of Ontario. The museum was devoted to the history and technology of the wine and spirit industry. The museum focused on wine-making and distillation, as well as barrel-making and cork manufacturing. The museum was located adjacent to the Seagram Distillery in Waterloo, Ontario. In 1997, the museum closed due to lack of funds.