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A facile entry to α-chloro-β-hydroxy ketone derivatives via SnCl 4 ·5H 2 O-catalyzed regioselective chlorohydroxylation of α,β-unsaturated carbonyl compounds is described. This reaction proceeded in water and is a rare example of Selectfluor serving as a chlorine source. The utility of the products was highlighted by the transformations to β-dicarbonyl compound and highly substituted 1,4-dioxane derivative. Some mechanistic investigations were also carried out, which suggested that a radical pathway was more likely to be involved.

isolation and structure elucidation of loniaceticiridoside (I) and lonimalondialiridoside (II)

The novel cluster compounds [Cu(en)2(H2O)] [Cu(en)2] 4{AsNb9V7O44 }·8H2O (I) and [Cu(en)2(H2O)] [Cu(en)2] 4H{AsNb8V8O44 }·11H2O (II) are prepared in 41 and 38% yield, resp., by solvothermal reaction of K7HNb6O19, Cu(OAc)2, Na2VO3, As2O3, and en under nearly identical conditions (HCl, H2O, autoclave, 160 °C, 5 d) except for the pH value which should be in the range 10.3—10.6 for (I) and 10.7—11.0 for (II).

isolation, structure elucidation, biogenetic pathway and HIV-1 replication inhibitory activity

The absolute configuration of title compound (I) is preliminary assigned using circular dichroism data.

The reaction, when carried out under optimized conditions A), affords a mixture of the desired ring system and a condensation product.

In this article, a practically interesting route for the diastereoselective synthesis of phenylpropanolamines has been demonstrated for the first time. Using racemic O-tert-butyldiphenylsilyl (TBDPS) cyanohydrins as the starting materials, various syn phenylpropanolamines and derivatives (e.g., norpseudophedrine) have been successfully prepared in exellent diastereoselectivity via a practically interesting process.

A variety of pharmaceutically important 3-methyleneindolinones are synthesized via a hitherto unreported oxidative tandem acetoxypalladation/C—H activation process.

The preparation of thiols (III) proceeds with reasonable diastereo- and enantioselectivity.

The new compounds (IV), (VI), and (VIII) are characterized by single crystal XRD, UV/VIS spectroscopy, and magnetic and electrochemical measurements.

An enantioselective 1,6-Michael addition reaction of arylthiols to a wide range of 3-methyl-4-nitro-5-alkenyl-isoxazoles catalyzed by readily available Takemoto's thiourea catalyst has been developed. This reaction provides a useful catalytic method for the synthesis of optically active chiral sulfur compounds bearing a 4-nitroisoxazol-5-yl moiety in high to excellent yields (up to 97%) and high enantioselectivities (up to 91% ee). Significantly, the potential utilities of the protocol had been further demonstrated by gram-scale reaction and the versatile conversions of some resulting products into other functionalized and useful compounds.

The process is highly efficient for the preparation of alkaloid structures and drug candidates.