Goodwin-Lions-type sp2N/sp3N hybrid ligands R-BINAN-R'-Py possessing a C2 axis binaphthyl skeleton have been designed and synthesized. Combination of the new non-phosphine ligand with Ru(pi-CH2C(CH3)CH2)2(cod) has been revealed to catalyze the hydrogenation of aromatic ketones with high enantioselectivity of up to 99% ee. The reaction proceeds essentially without the need for any bases, but the reactivity is enhanced by the addition of KOt-C4H9 attaining an S/C ratio of up to 10 000. The success should expand the range of possibilities in designing catalysts not only for hydrogenation but also for many other reactions.

Seven new isomalabaricane derivatives, rhabdastins A-G (1-7), and a new monocyclic triterpene glycoside, rhabdastoside A (8), have been isolated from the methanol extract of the sponge Rhabdastrella globostellata, collected at Amami-oshima, Japan. Three of them were isolated as their corresponding methyl esters, rhabdastins A-D (1-3). Their structures were determined on the basis of spectroscopic and X-ray diffraction analyses. The isolated compounds were evaluated for their cytotoxicity against the proliferation of promyelocytic leukemia HL-60 cells. Compounds 4, 5, 7, and 11, possessing a cyclopentane side chain, exhibited weak activity, with IC(50) values of 21, 29, 44, and 11 μM, respectively, while compounds 1, 2, and 3, with a 2-substituted-propanoate side chain, were inactive at 100 μM. In addition, the mechanism of cytotoxicity of compounds 4 and 5 was investigated.

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R-BINAN-R'-Py. -The combination of the ruthenium-allyl complex RUT, optically active ligand BPAN, and tBuOK in an equimolar ratio represents an efficient catalytic system for the hydrogenation of acyclic and cyclic aromatic ketones. A detailed study with acetophenone (Ia) reveals that tBuOK is not essential, but the reactivity without the base is halved. In the case of indanone, hydrogenation only takes place in the absence of base. -(HUANG, H.; OKUNO, T.; TSUDA, K.; YOSHIMURA, M.; KITAMURA*, M.;