A short and unambiguous total synthesis of furans 2a-c, natural products isolated from the roots of Trichogonia prancii, is described. Some differences in melting points and 1H NMR spectroscopic data were found when compared with those published for the natural products, which can be attributed to typographical errors in the original papers.
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Based on the observed instability of bromo furanmethanol 7a, analog 2d was rapidly purified by column chromatography and submitted immediately to the next reactions. However, we later knew that 2d had been previously prepared and characterized by Bohlmann et al. by sodium borohydride reduction of natural 2a [1a].
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To the best of our knowledge potential biogenetic precursors of 2a-c (e.g. 1b) have been isolated from several Trichogonia species, but these furan compounds are produced only by T. prancii from which, surprisingly, the biogenetic precursors have not yet been isolated. See reference 1.
