Chem Asian J
January 2022
ortho-Alkynylarylketone derivatives were employed as key precursors for a one-pot synthesis of arylnaphthalenelactone and furanonaphthol libraries. In this work, we discovered a cost-effective protocol to prepare arylnaphthalenelactones in one-pot using inexpensive starting material, malonate ester, which was conveniently functionalized leading to a variety of structures. Moreover, we also found an unexpected oxy-dearylation reaction which could be used to synthesize furanonaphthol analogs.
View Article and Find Full Text PDFEighteen hybrid compounds between 8-bromo-2-fluoro-isocryptolepine (4) and 1,2,3-triazole were synthesized via azide rearrangement-annulation reaction. Compound 4 underwent regioselective N-propargylation and click reaction to form 8-bromo-2-fluoro-isocryptolepine-triazole hybrids 11 which were evaluated for cytotoxic activity. Compound 11 c containing 1-anisyltriazole was the most effective in inhibiting HepG2, HuCCA-1 and A549 cell lines (IC values of 1.
View Article and Find Full Text PDFHalogenated natural products number in the thousands, but only in rare cases are the evolutionary advantages conferred by the halogens understood. We set out to investigate the lissoclimide family of cytotoxins, which includes several chlorinated members, because of our long-standing interest in the synthesis of chlorinated secondary metabolites.Our initial success in this endeavor was a semisynthesis of chlorolissoclimide (CL) from the commercially available sesquiterpenoid sclareolide.
View Article and Find Full Text PDFReadily available 1,2-amino alcohols provide the framework for a new generation of chiral carboxylic acid catalysts that rival the acidity of the widely used chiral phosphoric acid catalyst ()-TRIP. Covalently linked thiourea sites stabilize the carboxylate conjugate bases of these catalysts via anion-binding, an interaction that is largely responsible for the low p values. The utility of the new catalysts is illustrated in the context of challenging [4 + 2] cycloadditions of salicylaldehyde-derived acetals with homoallylic and bishomoallylic alcohols, providing polycyclic chromanes in a highly enantioselective fashion.
View Article and Find Full Text PDFortho-Carbonylarylacetylenols have been employed for the synthesis of dihydronaphthofurans via AgTFA-catalyzed annulation reaction. A broad range of substrates both ortho-keto- and ortho-formylarylacetylenols could be employed in this transformation providing the desired products in good yields. However, the reaction pathways of these two substrates are different.
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