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8-Methoxy-1-tetralone was synthesized in a concise and efficient manner involving a sequential palladium-mediated cross-coupling reaction (Heck), catalytic hydrogenation, and intramolecular acylation mediated by Eaton's reagent or Lewis acids. The pivotal step in the synthesis was the use of a bromine substituent at the benzenoid C4 position of the intermediate methyl 4-arylbutyric ester to ensure cyclization ortho to the methoxy moiety and obviate cyclization at the para position to the thermodynamically preferred 6-methoxy-1-tetralone, the sole product obtained in the absence of this blocking group.

Synthesis and Biological Activity of 23-Ethylidene-26-hydroxy-22-oxocholestaneDerivatives from Spirostanic Sapogenins. -Three new cholestane frameworks of type (II) are obtained by reductive cleavage of the F-ring of oxoepoxycholestane derivatives (I) without detectable competing 1,2-reduction of the α,β-unsaturated carbonyl group at C-22. This selectivity is attributed to steric hindrance around C-22, which is corroborated by the finding that Luche's reagent is unable to effect 1,2-reduction of the C-22 carbonyl of epoxycholestenes (I). Utilizing this reagent, reduction of the carbonyl group occurs to afford a diastereomeric mixture of epimeric alcohols (III) and (IV). The selectivity of this reaction is totally reversed in the absence of cesium chloride. Steroids (I), (II) and (III) display some anti-cancer activity against CEM, and (Ib) reveals cytotoxic activity against the MCF7 line as well. -(PEREZ-DIAZ, J. O. H.; RAROVA, L.; MUNOZ OCAMPO, J. P.; MAGANA-VERGARA, N. E.; FARFAN, N.; STRNAD, M.; SANTILLAN*, R.; Eur. J. Med. Chem. 51 (2012) 67-78, http://dx.