The first total synthesis of marine anti-cancer meroterpenoids dysideanone B and dysiherbol A have been accomplished in a divergent way. The synthetic route features: 1) a site and stereoselective a-position alkylation of a Wieland-Miescher ketone derivative with a bulky benzyl bromide to join the terpene and aromatic moieties together and set the stage for subsequent cyclization reactions; 2) an intramolecular radical cyclization to construct the 6/6/6/6-tetracycle of dysideanone B and an intramolecular Heck reaction to forge the 6/6/5/6-fused core structure of dysiherbol A. A late-stage introduction of the ethoxy group in dysideanone B reveals that this group might come from the solvent ethanol. The structure of dysiherbol A has been revised based on our chemical total synthesis.

The first total synthesis of marine anti‐cancer meroterpenoids dysideanone B and dysiherbol A have been accomplished in a divergent way. The synthetic route features: 1) a site and stereoselective α‐position alkylation of a Wieland–Miescher ketone derivative with a bulky benzyl bromide to join the terpene and aromatic moieties together and set the stage for subsequent cyclization reactions; 2) an intramolecular radical cyclization to construct the 6/6/6/6‐tetracycle of dysideanone B and an intramolecular Heck reaction to forge the 6/6/5/6‐fused core structure of dysiherbol A. A late‐stage introduction of the ethoxy group in dysideanone B reveals that this group might come from the solvent ethanol. The structure of dysiherbol A has been revised based on our chemical total synthesis.

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Pure 2122 phase and 2223 phase superconducting TlCaBaCuO thin films have been reproducibly prepared on (100)LaAlO3 substrates by dc magnetron sputtering using a pair of superconducting Tl2Ca2B2Cu3O10 targets and post-annealing at different temperatures. X-ray diffraction analysis indicates that the films are highly c-axis oriented perpendicular to the film surface for both types of the thin films. The critical transition temperature Tc(R = 0) = 98 K and critical current Jc(77 K)=1.0×105 A/cm2 can be obtained for 2122 phase films, and for 2223 phase films Tc(R = 0) = 115 K and Jc(77 K) = 5.5 × 105 A/cm2 can be obtained.

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