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The [2,3]-sigmatropic rearrangement of sulfonium ylides bearing substituted allyl groups creates two contiguous stereocentres. Low diastereoselectivity is typically observed from commonly used α-diazocarboxylic ester precursors. High diastereoselectivity was previously revealed in a gold-catalyzed multicomponent route into allyl sulfonium ylides by reaction of ynamide, oxidant and allyl sulfides. The effect of substrate modifications on the diastereoselectivity have been studied, with N -phenyl methanesulfonamide derived ynamides proving the most effective. This report includes an enhanced experimental procedure, and a demonstration that the gold-catalyzed process remains highly effective at −78 °C. Image 1 [ABSTRACT FROM AUTHOR]

Parthenolide exhibits anti-leukaemia activity, whilst its synthetic modification to impart improve drug-like properties, including 1,4-conjugate addition of primary and secondary amines, have previously been used, 1,4-addition of aniline derivatives to parthenolide has not been fully explored. A protocol for such additions to parthenolide is outlined herein. Reaction conditions were determined using tulipane as a model Michael acceptor. Subsequently, aniline-containing parthenolide derivatives were prepared under the optimised conditions and single crystal X-ray diffraction structures were resolved for three of the compounds synthesised. The synthesised derivatives, along with compounds resulting from a side reaction, were tested for their in vitro anti-leukaemia activity using the chronic lymphocytic leukaemia (CLL) MEC1 cell line. Computational studies with the 2RAM protein structure suggested that the activity of the derivatives was independent of their in silico ability to dock with the Cys38 residue of NF-κB. Image 1 • Squaric acid-catalysed 1,4-conjugate addition of aniline derivatives to parthenolide. • Anti-chronic lymphocytic leukaemic activity. • Crystal structures of some products and by-products. [ABSTRACT FROM AUTHOR]

Abstract: A library of 1,4-benzodiazepines has been synthesized and evaluated against Trypanosoma brucei, a causative parasite of Human African trypanosomiasis. Benzodiazepines possessing a P2- transporter motif were found to have MIC values as low as 0.78μM. [Copyright &y& Elsevier]

Abstract: Treatment of (ArF′)2Zn(OEt2)2 (ArF′=4-C6F5C6F4) with 2equiv. of benzonitrile, 4-(phenyl)benzonitrile, 4-(pyrrolyl)benzonitrile, pyridine, 4-(phenyl)pyridine or 4-(pyrrolyl)pyridine in dichloromethane afforded the corresponding adducts (ArF′)2ZnL2 in near quantitative yield. The 2,2′-bipyridine adduct was prepared similarly. Multinuclear NMR spectroscopy indicated that zinc′s four-coordinate character was maintained in solution. The pyridine complex crystallized from dichloromethane with a solid-state structure free of face-to-face aryl–aryl interactions. In contrast, the 4-(pyrrolyl)pyridine adduct crystallized from both dichloromethane and 1,2-difluorobenzene, with solvent of crystallization, but otherwise essentially identical supramolecular architectures assembled through aryl–aryl synthons, including a face-to-face pentafluorophenyl–pyrrole interaction. [Copyright &y& Elsevier]

Abstract: The reaction between 1-boranyl-1,3,5-triaza-7-phosphaadamantane ligand N–B–PTA(BH3) and [Cp∗RhCl(μ-Cl)]2 affords [Cp∗Rh{N–B–PTA(BH3)}Cl2] (3) or [Cp∗Rh{N–B–PTA(BH3)}2Cl]Cl (5) containing one or two P-bonded boronated PTA ligands. The hydride [Cp∗Rh{N–B–PTA(BH3)}H2] (8) was also obtained by reaction of 3 with NaBH4 and alternatively by direct hydroboration of [Cp∗Rh(PTA)Cl2] with excess NaBH4. Moderately slow hydrolysis of the N-boranyl rhodium complexes affords dihydrogen, H3BO3 and the corresponding PTA derivatives, including the water-soluble dihydride [Cp∗Rh(PTA)H2] (9). Finally, the reaction of 8 with electron poor alkynes gives the alkene complexes [Cp∗Rh{N–B–PTA(BH3)}(η2-CH2 =CHR)] (R=Ph, 10; C(O)OEt, 11) as a mixture of rotamers η2-coordinated to rhodium without affecting the N–BH3 moiety. The X-ray crystal structures of 3 and 10 were also obtained and are here discussed. [Copyright &y& Elsevier]