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The enantioselective formal [3 + 3] annulation reaction of isatin-derived β,γ-unsaturated α-ketoesters with 3-hydroxy-4H-chromen-4-ones or 2-hydroxy-1,4-naphthoquinone was successfully implemented under catalysis of quinine-derived bifunctional tertiary amine-thiourea catalysts. The efficient tandem Michael-cyclization has provided facile access to optically active spiro[oxindole-pyrano[3,2-b]chromenone] and spiro[oxindole-benzo[g]chromene-dione] derivatives in high yields with excellent diastereo- and enantioselectivities.

Based on oxindole-derived diketones as the substrates, asymmetric desymmetrizing intramolecular aldol or aldol condensation reactions are reported, which are catalyzed by a Trost bis-ProPhenol dinuclear zinc complex. The corresponding spiro[cyclohexanone-oxindole] derivatives were obtained in good yields with moderate to good enantioselectivities.

A series of enantiomerically enriched 3,4-dihydrocoumarins containing contiguous quaternary and tertiary stereogenic centers has been efficiently constructed via domino asymmetric Michael addition/transesterification reactions of azlactones with o-hydroxychalcones using a quinine-derived thiourea as bifunctional organocatalyst. Under mild reaction conditions, the optically active 3,4-dihydrocoumarins were generally obtained in 63–96% yields with >20:1 dr and 81–96% ee.

The scalable reaction delivers the products in very high yield, with excellent diastereoselectivity and high enantioselectivity.

isolation, structure and cytotoxicity of five new secosteroids (I) and seven known analogues

Optimum reaction conditions are examined for the asymmetric Henry reaction catalyzed by a new chiral Schiff base.

Eleven diarylheptanoids (1-11) were isolated from rhizomes of Curcuma kwangsiensis, together with seven known compounds. Their structures were elucidated by 1D and 2D NMR, circular dichroism (CD), and accurate mass measurements. Inhibitory effects of the isolated compounds on nitric oxide production in lipopolysaccaride-activated macrophages were evaluated. Compounds 1, 2, and 3 showed strong inhibitory activity on NO production with IC(50) values of 3.13, 2.81 and 2.41 μM, respectively.

Among 14 oxidometallic species examined for catalytic phosphorylation of the tested alcohols, oxidomolybdenum tetrachloride (MoOCl 4 ) was found to be the most efficient with a negligible background reaction mediated by triethylamine (Et 3 N). The new catalytic protocol can be applied to the chemoselective phosphorylations of primary, secondary and tertiary alcohols as well as the substitution-free phosphorylations of allylic, propargylic, and benzylic alcohols. Functionalized alcohols bearing acetonide, tetrahydropyranyl ether, tert-butyldimethylsilyl ether, or ester group are also amenable to the new catalytic protocol. The most difficult scenarios involve substitution-free phosphorylations of 1-phenylethanol and 1-(2-naphthyl)ethanol which can be effected in 95 and 90% yields, respectively. ESI-MS, IR, 1 H, and 31 P NMR spectroscopic analyses of the reaction progress suggest the intermediacy of an alkoxyoxidomolybdenum trichloride-triethylamine adduct such as [(RO)Mo(O)Cl 3 -Et 3 N] to be responsible for the catalytic turnover.

A series of carbamates, amides, N-tosyl amides, (hetero)arenes, and hydrogen phosphines/phosphites has been examined as nucleophiles for (hetero)Michael-type additions to enones and enamides catalyzed by amphoteric vanadyl triflate under mild and neutral conditions. The newly developed C−N, C−P, and C−C bond-formation protocols were carried out smoothly in good to high yields without intervention of any 1,2-additions.